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Justin Richmond On the Particular Brilliance of EW&F's "Keep Your Head to the Sky"
Streaming Concert Watch 1/6: Trent Reznor, Billy Corgan and More
Kyle Hubbard Celebrates Tax Day By Giving Away Raps Four Free
| Houston Music |
Nathan Smith | April 15, 2016 | 8:44am
Local rapper Kyle Hubbard just can't stand the thought that you might forget about him. Or maybe he just can't stand the thought of you bumping stale beats out of your trunk. Either way, he's debuting some new hip-hop tunes today, and the price is right: completely free.
It hasn't been so long since Hubbard last dropped a project. Last September, he delivered Majestic Hotel, a comeback album that was written and recorded after a self-imposed Arkansas exile from the rap game. It was the debut release from Roologic Records, the label headed by longtime local DJ Ruben Jimenez, and it looked like the beginning of a fruitful H-Town partnership. Alas, it was both beginning and end; Hubbard and the label have parted ways.
The rapper says that the separation was amicable, with both sides headed for bigger, better things. And to prove it — to himself, perhaps, as much as anyone — Kyle Hubbard celebrated his renewed independence by hitting the studio with some buds last weekend and putting in an all-nighter. The result is a group of four new songs that he's released on his Bandcamp page today titled Four Free.
Four Free by Kyle Hubbard
Guilla Aims Straight For Outer Space On Children of the Sun
Hubbard says that some of his closest colleagues, such as his live collaborator DJ Discipline and his fellow MC Guilla, encouraged him to get his name back out there on a new playlist. Initially, at least, it was a hard sell.
"DJ Discipline, when we were rehearsing for South By Southwest, he was like, 'You really need to put more music out,' the rapper says. "And at first, I was like, 'Dude, fuck that. I don't have the time; I don't have the willpower. I'm not into that at all right now.' And then, the thing me and Roologic happened and I thought, 'Well, I need to do something. I need to kind of reassert myself and show everybody that everything is going to be operational as usual.'
"So, I hit DJay Cas up and ran the idea by him, and he pretty much ran with it instantly," Hubbard continues. "It was one conversation, and then Cas was giving me four beats."
Djay Cas has been Hubbard's go-to producer for some time now. The two met years ago, posting opinionated bullshit together on the same rap message board. Before he could talk himself out of it, the rapper booked time at the iMix studio on the Southwest Side last Saturday and got to spittin'. The final product would have to be ready in a week, before Hubbard takes the stage tomorrow at Guilla's album-release concert at Raven Tower.
"It happened, like, in two weeks, which is insane for me," he says. "I work very good with a deadline; if I don't have a deadline, I dick around. Recording everything in one session in one night is something that I didn't know I could do. It's not something that I would have even thought about doing had it not been for such a strict deadline that I put on myself."
It might have been understandable if Hubbard had chosen to go it alone on the new project, in that weird way that newly single people refuse to date anybody for a while. But for Four Free, Kyle went in the opposite direction, calling in features from local standouts Fullmetal and T2 the Ghetto Hippie as well as Mississippi's Fred Nice.
And naturally, Hubbard had DJay Cas in his corner, who dusted off a couple of old beats for the project and put together two new ones just for the occasion. Typically, Hubbard is a pretty hands-on guy when it comes to putting tracks together, but this time out, there simply wasn't the time for second-guessing.
"I'm lucky to work with someone as dope as Cas, because when it comes to something like Four Free, where I have to essentially put my fate into other people's hands, I know that I can do that with him," Hubbard says. "He was essential to having the idea that I even could do something like this in such a short amount of time, because I knew that I could let him take the wheel completely and I'd still be happy with what he does for me."
A perfect example of that trust working out beautifully is Four Free's best track, "Same Old Song." Every Kyle Hubbard release seems to contain a love letter to Houston, but this one is a lot more syrupy than he's ever dared before.
"Normally, Kyle will come to me with a concept and we'll map it out from there and he'll have me switch up pieces, but this was something that I kind of sold him on," says DJay Cas. "I don't want to say it's a brand-new sound, but I think it's a new form of our sound. It's the next level."
"Same Old Song" is heavily indebted musically to the swang-and-bang Southside anthems of yore, but lyrically, Hubbard refuses to play the gangsta. With sterling assists from T2 and Fred Nice, the rapper manages to pay his respects to classic Houston hip-hop while still acknowledging life in the city far beyond the confines of MacGregor Park.
"The hook was already on the song when I heard it, and it's straight-up H-Town," Hubbard says. "I was like, 'Dude, I love this kind of shit, but I don't know if I'm an accurate representation of that side of Houston.' Cas really sold me on the way that I need to approach it. It's for every Houstonian in every corner of the city. It's not just, like, the draped-up/dripped-out or the backpacker kids. It touches on every subculture that makes Houston great."
By pushing Hubbard just a bit outside his comfort zone, DJay Cas helped to create one of the rapper's best songs yet. And now that Kyle Hubbard is a free agent again, expect to hear plenty more new explorations from him and his merry band of collaborators real soon.
"We're just going to keep the ball rolling," DJay Cas says. "We have more to come, but this is just to hold people off for right now."
Recommend you savor the new one while you can—the next one might just cost you something.
Kyle Hubbard unveils Four Free live on Saturday night at Raven Tower for Guilla's Chidren of the Sun release party, with Guilla, Bizzythowed, Mojave Red, iLL-Faded and Mark Drew. Free Admission. Doors open at 6 p.m.
Keep the Houston Press Free... Since we started the Houston Press, it has been defined as the free, independent voice of Houston, and we would like to keep it that way. Offering our readers free access to incisive coverage of local news, food and culture. Producing stories on everything from political scandals to the hottest new bands, with gutsy reporting, stylish writing, and staffers who've won everything from the Society of Professional Journalists' Sigma Delta Chi feature-writing award to the Casey Medal for Meritorious Journalism. But with local journalism's existence under siege and advertising revenue setbacks having a larger impact, it is important now more than ever for us to rally support behind funding our local journalism. You can help by participating in our "I Support" membership program, allowing us to keep covering Houston with no paywalls.
Houston Music
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Oliver Penn Releases New Single "Squash Blossom"


A fancy looking cake with a very light strawberry mousse molded with ladyfingers, then topped with seasonal berries.
Ingredients: Egg, flour, egg white, butter, sugar, gelatin, whipped cream, and lady fingers.
Pairing suggestion: Pair with tea or coffee.


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Bristol Rugby
Rugby rumours and transfer news: Worcester Warriors lock considering offers, Samoan international joins Knights
The latest on Will Spencer, Josh Tyrell, Quade Cooper, Joe Cokanasiga, Will Chudley and Steve Mafi
John Evely
With Bristol Rugby likely to be back at the top table of European rugby next season we take a look at all the transfer news and rumours at the clubs they could be playing next season.
Will Spencer of Worcester Warriors charges upfield during the Aviva Premiership match against London Irish at Sixways Stadium
Offers out there for Worcester Warriors lock - rumour
Worcester Warriors second row Will Spencer is rumoured to be a top target for Leicester Tigers who are in need of some beef in their pack.
Spencer, who is out of contract at Worcester at the end of the season revealed there were "offers out there" for him to consider.
Talking to the Worcester News he said: "There are offers out there, but I am very happy at Worcester and I'll speak to Solly [director of rugby Alan Solomons] and we'll see."
Spencer pulled on the England senior shirt for the first time in May in the non-cap match against the Barbarians, coming off the bench.
Revealed: Bristol Rugby coach Mark Bakewell's contract situation
Samoan international Josh Tyrell signs for Championship club - done real
Doncaster Knights are delighted to announce that Samoan international back-rower Josh Tyrell has signed for the club until the end of the season.
Tyrell arrives in Doncaster following a successful Mitre 10 Cup campaign with North Harbour in New Zealand, aiding the side in reaching the Premiership semi-finals where they lost out to eventual champions Canterbury.
Tyrell 's Mitre 10 Cup form led to a call-up to the Manu Samoa squad for November's international tour where he was named in the starting line-up against Scotland. Tyrell marked his debut with a first-half try in a thrilling 44-38 defeat in front of just under 70,000 at Murrayfield.
The forward got his second cap a fortnight later against England proving his versatility as he lined up alongside Bristol's Chris Vui in the Samoan second row and will now aim to play a big part in the Knights' 2018.
Quade Cooper of the Barbarians offloads the ball in a tackle by Ned Hanigan of the Wallabies
Rugby Pod Rumours
On the Rugby Pod podcast host Andy Goode and Jim Hamilton discuss rugby transfer rumours they have heard each week, this is what was said this week.
Rumours continue to circle that Quade Copper , who is out of contract at the Queensland Reds, is a target of Ulster who are looking for a long-term replacement at fly-half.
Exeter Chiefs scrum half Will Chudley is reportedly a target for Bath Rugby. Chudley, 23, has played 113 games for the Aviva Premiership champions since joining from Newcastle Falcons in 2012.
Bath are also said to be interested in signing London Irish winger Joe Cokanasiga as they look to replace Matt Banahan with a like-for-like replacement after the big utility back joined Gloucester this week.
Three of Bristol Rugby's brightest young talents sent out on loan to Championship rivals
Cokanasiga, still just 20, joined the Exlies' academy ahead of the 2016/17 season and made a big impression during London Irish's march to promotion from the Greene King IPA Championship.
The Fijian born flyer was part of Eddie Jones' England set-up that travelled to Argentina in the summer of 2017, a hamstring injury preventing him from playing in the games.
The a move to Bath could prove costly as Cokanasiga signed a four-year contract extension n the summer ahead of the club's return to the Aviva Premiership and he has been call-up to the England training squad in the build-up to the 2018 NatWest Six Nations.
Former Tigers forward Steve Mafi is reportedly wanted back by Leicester from French Top 14 club Castres. The two clubs face each other tomorrow in the Champions Cup and Mafi has been named on the bench for the French side.
Rugby rumours and transfer news: Quins lock down Marcus Smith, Exeter Chiefs flanker to move
The RFU Championship
Nigel Pearson delivers honest and damning assessment of Bristol City's defeat at Fulham
Bristol City FCAleksandar Mitrovic claimed a first-half hat-trick after Antoine Semenyo's brace had given Bristol City the perfect platform to force a result

redpajama_set_name: RedPajamaCommonCrawl


"A new and unregistered 2019 Coachman VIP 460 caravan which is due to arrive in MAY 2019. Available to pre-order now. Featuring a standard VIP specification and colour scheme with a 3 year warranty and 10 year body integrity warranty. RRP shown excludes usual manufacturers delivery charge of £545."


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Great, thanks for the confirmation that it's working so far.
So, this was driving me bonkers. I had sent you that logcat, but I wanted to get to the bottom of this because I did another factory reset and only installed MobiLinc just to find that it worked fine. So I knew it had to be an app compatibility issue.
Since I'm rooted it was relatively easy for me to disable certain apps (a.k.a freeze them) using Titanium Backup. I then went through and disabled apps until I found the culprit, and it ended up being caused by Light Flow. I'm not sure if the same app is causing issues for everyone in this thread, but my issue was resolved by disabling that app.
I rely pretty heavily on Light Flow though (it's always one of the first apps I install), and it's pretty popular given that the free version has been downloaded over a million times. Once I got this figured out though I was able to disable/freeze the app, make my changes and set up the MobiLinc widgets, and then unfreeze the app. Thankfully all the critical areas in MobiLinc work fine with Light Flow installed.
Hopefully this helps you guys pinpoint the issue, and gives some relief to others with the same problem. I have no idea why the two apps conflict with each other since Light Flow is a notification management app and MobiLinc doesn't use notifications, but hopefully you guys can have some fun working that out.
Thanks Ryan! We're investigating...Will post back with our findings.
We've released a bug-fix version of MobiLinc for Android this morning that addresses the OS 4.1/4.2 issue identified in this forum post.
Please update to version 1.2.2 from the Play store or select "Check for Updates" from inside of your MobiLinc non-market app to download the latest.
It may take Google up to 24 hours to roll out the update to all of their Play servers.


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Structural basis for electron transport mechanism of complex I-like photosynthetic NAD(P)H dehydrogenase
Structural insights into NDH-1 mediated cyclic electron transfer
Chunli Zhang, Jin Shuai, … Ming Lei
Structure of the complex I-like molecule NDH of oxygenic photosynthesis
Thomas G. Laughlin, Andrew N. Bayne, … Karen M. Davies
Structural basis for energy and electron transfer of the photosystem I–IsiA–flavodoxin supercomplex
Peng Cao, Duanfang Cao, … Mei Li
Architecture of the chloroplast PSI–NDH supercomplex in Hordeum vulgare
Liangliang Shen, Kailu Tang, … Xing Zhang
Structural basis for the assembly and quinone transport mechanisms of the dimeric photosynthetic RC–LH1 supercomplex
Peng Cao, Laura Bracun, … Lu-Ning Liu
Allophycocyanin A is a carbon dioxide receptor in the cyanobacterial phycobilisome
Alejandra Guillén-García, Savannah E. R. Gibson, … Martin J. Cann
Structural insight into the mechanism of energy transfer in cyanobacterial phycobilisomes
Lvqin Zheng, Zhenggao Zheng, … Ning Gao
The function of PROTOPORPHYRINOGEN IX OXIDASE in chlorophyll biosynthesis requires oxidised plastoquinone in Chlamydomonas reinhardtii
Pawel Brzezowski, Brigitte Ksas, … Jean Alric
Structural and functional insights into the tetrameric photosystem I from heterocyst-forming cyanobacteria
Lvqin Zheng, Yanbing Li, … Ning Gao
Xiaowei Pan ORCID: orcid.org/0000-0002-9672-46491 na1,
Duanfang Cao ORCID: orcid.org/0000-0002-1229-39501 na1,
Fen Xie1,2 na1,
Fang Xu2,3 na1,
Xiaodong Su1,
Hualing Mi3,
Xinzheng Zhang ORCID: orcid.org/0000-0002-0114-02701,2,4 &
Mei Li ORCID: orcid.org/0000-0002-1742-23601
Nature Communications volume 11, Article number: 610 (2020) Cite this article
Cryoelectron microscopy
NAD(P)H dehydrogenase-like (NDH) complex NDH-1L of cyanobacteria plays a crucial role in cyclic electron flow (CEF) around photosystem I and respiration processes. NDH-1L couples the electron transport from ferredoxin (Fd) to plastoquinone (PQ) and proton pumping from cytoplasm to the lumen that drives the ATP production. NDH-1L-dependent CEF increases the ATP/NADPH ratio, and is therefore pivotal for oxygenic phototrophs to function under stress. Here we report two structures of NDH-1L from Thermosynechococcus elongatus BP-1, in complex with one Fd and an endogenous PQ, respectively. Our structures represent the complete model of cyanobacterial NDH-1L, revealing the binding manner of NDH-1L with Fd and PQ, as well as the structural elements crucial for proper functioning of the NDH-1L complex. Together, our data provides deep insights into the electron transport from Fd to PQ, and its coupling with proton translocation in NDH-1L.
During oxygenic photosynthesis, light energy is utilized by photosystems I and II (PSI and PSII) to drive the electron transport, which can be classified into two types, the linear electron transport/flow and the cyclic electron transport/flow1,2. During LEF, electrons are extracted from water molecules by PSII and transported to PSI through cytochrome b6f (Cytb6f) and free electron carrier including plastoquinone (PQ), before being ultimately used to reduce NADP+ to NADPH. Simultaneously, a proton gradient across the thylakoid membrane is generated and drives the ATP synthase to produce ATP3. Both NADPH and ATP are required for the subsequent CO2 assimilation during the Calvin–Bensen–Bassham cycle and other cellular metabolisms2,3. During the CEF process, the electrons are recycled between PSI and Cytb6f through PQ pool. CEF functions without PSII, simply creating the transmembrane proton gradient, which allows only ATP production without generating NADPH4,5. LEF alone probably generates insufficient ATP to balance the ATP/NADPH consumption for CO2 assimilation6,7,8, whereas CEF increases the produced ATP/NADPH ratio9, thus is important for achieving high efficiency of the Calvin–Bensen–Bassham cycle, especially under multiple stressed conditions4,10,11,12, as well as for C4 photosynthesis13,14. In addition, photosynthetic organisms that are exposed to environmental stress usually exhibit increased demand for ATP15, therefore, CEF is crucial for the quick response of phototrophs to the changing environment. Furthermore, CEF plays an essential role in photoprotection by generating a large transmembrane proton gradient, thereby inducing energy dependent quenching to dissipate excessively absorbed energy9,16,17,18,19.
In both cyanobacteria and plants, a type-I NAD(P)H dehydrogenase-like (NDH-1) complex is crucial for CEF and respiration. NDH-1 complex accepts electrons from electron carrier ferredoxin (Fd) or NAD(P)H in PSI acceptor side, and transfers them to Cytb6f through PQ20,21. NDH-dependent CEF was previously suggested to fine-tune the chloroplast redox state, and to prevent overreduction of the stroma under stress2,14. The NDH-1 complexes belong to the NAD(P)H:Quinone oxidoreductase family that includes the complex I (NADH dehydrogenase) of the respiratory chain in bacteria and mitochondria15,22. Cyanobacteria possess several types of NDH-1 complexes, namely NDH-1L/1L′ (large), NDH-1M (medium), and NDH-1S/1S′ (small), differing in size and the isoforms of NdhD/NdhF subunits, and the latter two types can further associate into NDH-1MS/NDH-1MS′23,24. NDH-1L containing NdhD1/NdhF1 is involved in CEF around PSI and respiration15,20. The NDH-1L complex and bacterial complex I form a similar L-shaped architecture and share 11 conserved subunits. In addition, cyanobacterial NDH-1L possesses eight oxygenic photosynthesis-specific (OPS) subunits25, namely NdhL26, NdhM, NdhN27, NdhO28, NdhP, NdhQ29, NdhS30, and NdhV31,32, but lacks three hydrophilic subunits, which contain the NADH binding site in bacterial complex I33. These earlier results were confirmed by recent studies showing that the photosynthetic NDH complex binds Fd as the electron donor, rather than NADPH34,35. The electron delivered from Fd is eventually transferred to PQ which is bound within the NDH complex.
Two structures of NDH-1L from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 were recently reported35,36. These studies identified the structures and locations of 18 subunits (lacking NdhV), providing solid foundations for better understanding the architecture and assembly of the NDH-1L complex. NDH-1L in these two structures adopts a characteristic L-shaped architecture, which can be divided into membrane arm/domain and hydrophilic arm/domain, composed of ten and eight subunits, respectively. However, the structure and accurate location of the soluble subunit NdhV, which might be loosely associated with the complex31,32, remain unknown. Moreover, it was previously suggested that NdhS participates in Fd binding34,37, while another recent study proposed an alternative Fd binding pocket formed by NdhO36. To date, the exact Fd binding site in cyanobacterial NDH-1L remains to be elucidated. In addition, as only the apo form of NDH-1L was structurally characterized, the detailed interactions of PQ within photosynthetic NDH complex has not been determined, although a quinone-reaction chamber (Q chamber) was previously suggested in respiratory complex I, based on the substrate/inhibitor-bound structures from Thermus thermophilus (Tt complex I)38 and Yarrowia lipolytica (Yl complex I)39. To further advance our understanding of NDH functionality, we solved two single particle cryo-electron microscopy (cryo-EM) structures of NDH-1L from T. elongatus BP-1. Our results provide the structural model of NDH-1L containing NdhV, and reveal the detailed binding modes of Fd and PQ. Moreover, we observe a variety of conformational changes between our structure and previously reported NDH/complex I structures, thus shedding light on the electron transport process and its coupling with proton translocation.
We first solved the structure of NDH-1L complex purified from T. elongatus BP-1 (Supplementary Fig. 1) at an overall resolution of 3 Å (Supplementary Fig. 2, Table 1). Interestingly, we found that the NDH-1L complex binds a PQ molecule at a pocket above the membrane plane (Fig. 1a). We assume that this is an endogenous PQ molecule, which was trapped in the cyanobacterial NDH-1L complex during purification, as was earlier reported for Escherichia coli complex I40. Thus, we named this structure as NDH-PQ. Similar to the two previously reported cyanobacterial NDH-1L structures35,36, our NDH-PQ structure also contains 18 subunits (Fig. 1a), without any signs of association with NdhV. These results indicated that NdhV is loosely associated with other NDH subunits, in line with previous biochemical data31,32. In addition, we found that the NdhS subunit in the NDH-PQ structure exhibits weak cryo-EM density, suggesting that NdhS is also loosely associated. Previous reports showed that NdhV interacts with NdhS and requires NdhS for its stabilization31,32. Therefore, to obtain the intact NDH-1L in complex with Fd, we expressed and purified the proteins of Fd, NdhV, and NdhS from T. elongatus BP-1 via E. coli (Supplementary Fig. 1) and incubated the purified proteins with NDH-1L in order to increase their occupancy, and finally solved the structure of NDH-1L containing NdhV and in complex with Fd (NDH-Fd) at 3.2 Å resolution (Supplementary Fig. 3, Table 1). The NDH-Fd structure, highly similar with the NDH-PQ structure, contains all 19 NDH subunits, and binds one Fd molecule at the top of the hydrophilic arm (Fig. 1b). Supplementary Fig. 4 shows the representative cryo-EM densities of Fd and several subunits and cofactors of NDH-1L complex.
Table 1 Cryo-EM data collection and refinement and validation statistics.
Fig. 1: The NDH-PQ and NDH-Fd structures.
a Cartoon representation of the NDH-PQ structure viewed along the membrane plane. PQ is shown as orange spheres and indicated. b The overall structure of NDH-Fd viewed along the membrane plane. c The location of OPS subunits in NDH-1L complex. The eight OPS subunits are colored differently and indicated, while other subunits are shown in white.
The membrane arm with lipid and carotenoid molecules
The membrane arm in NDH-PQ and NDH-Fd structures are almost identical, seven subunits (NdhA-G) conserved in respiratory complex I constitute the membrane core, and three OPS subunits (NdhL, NdhP-Q) attach to the peripheral region. NdhP and NdhQ are located at the distal part, sandwiching NdhD from opposite sides, whereas NdhL is positioned adjacent to NdhA (Fig. 1c). Furthermore, we modeled two carotenoids and thirteen lipid molecules (Supplementary Fig. 4g–l) within the membrane arm in both NDH-PQ and NDH-Fd structures (Fig. 2). In addition to the previously described protein–protein interaction35,36, these nonprotein components greatly contribute to the integrity of the membrane arm. At the proximal region, two digalactosyldiacyl glycerol (DGDG) molecules fill the empty space between NdhA and NdhL from the luminal side, with one DGDG further hydrogen bonded with the N-terminal region of NdhC. In the vicinity of the two DGDGs, another lipid molecule is sandwiched by the first transmembrane helix (TMH) of NdhC and NdhG. Therefore, the three lipid molecules function in linking the three proximal subunits at the lumen (Fig. 2b). At the distal region, seven lipid molecules were observed, and six are located at the stromal side (Fig. 2a). Among the seven lipids, four and two are found to gather at the NdhF–NdhD, NdhD–NdhB interfaces, respectively (Fig. 2c). Moreover, two carotenoid (modeled as β-carotene) molecules greatly enhance the NdhF–NdhD interaction. One β-carotene (BCR1) is located near NdhP and sandwiched by two lipid molecules (Fig. 2d), together forming a cluster and serving as molecular glue, as was previously suggested by a NDH-1L structural study35. On the opposite side close to NdhQ, the second β-carotene (BCR2) molecule is almost parallel to the membrane plane and binds in a pocket below the horizontal helix of NdhF (Fig. 2e). This observed β-carotene secures the NdhF–NdhD interaction, comparable to a bolt-like feature. In addition to their function for light harvesting and energy quenching, carotenoid molecules are also crucial for the inter-subunit interaction and stabilization for the photosynthetic complexes41. The two β-carotene molecules result in the strong association between NdhF and NdhD, thus explaining the presence of a smaller NDH-1M complex in cyanobacteria, which lacks both NdhD and NdhF subunits42,43. In addition, our structures indicate that both NdhP and NdhQ form direct contacts with NdhD and NdhF, and further interact with interfacial lipids and carotenoids (Fig. 2d), thus contribute to the stabilization of NDH-1L complex, in line with the finding from previous reports that deletion of each subunit disassembles the NDH-1L complex44,45.
Fig. 2: The membrane arm with lipid and carotenoid molecules.
a Distribution of cofactors in NDH-Fd structure. Fe–S clusters are shown as spheres, PQ (orange), lipids (blue), and carotenoids (red) are shown as sticks. b Three lipid molecules (shown as ball-and-stick mode) contribute to the stabilization of NdhL, NdhA, NdhC, and NdhG. c The stromal side view of the lipid distribution at the distal part of the membrane arm. d Two carotenoid (BCR) and three lipid molecules participate in NdhF–NdhD interactions. e The binding pocket of BCR2. The color codes of subunits are the same as those in Fig. 1. The horizontal helix of NdhF is shown as blue cartoon. The BCR molecules are shown as red sticks. Lipid molecules are colored yellow for phosphatidyl glycerol (PG), gray for sulfoquinovosyldiacyl glycerol (SQDG), orange for monogalactosyldiacyl glycerol (MGDG), and blue for DGDG in b–e.
The hydrophilic arm and the interface between two arms
The NDH-Fd structure contains the complete hydrophilic arm composed of nine subunits, including NdhV (Fig. 3a), which was absent in both previously reported NDH structures. The four subunits conserved in respiratory complex I (NdhH-K) form the hydrophilic core of NDH-1L. Among them, NdhI and NdhK harbor two and one 4Fe–4S clusters (corresponding to the clusters N6a, N6b, and N2 from the respiratory complex I) essential for electron transport (Figs. 2a, 3a). Five OPS subunits (NdhM, NdhN, NdhO, NdhS, and NdhV) are located at the peripheral region, surrounding half of the hydrophilic core (Fig. 1c). Extensive interactions are formed between the conserved subunits and OPS subunits.
Fig. 3: The hydrophilic arm containing NdhV.
a The location of subunits in the hydrophilic domain. The nine NDH subunits in the hydrophilic domain are colored differently and labeled with the abbreviations of one letter (for example, letter V indicates subunit NdhV). The 4Fe–4S clusters are shown as spheres. b Overall structure of NdhV. c The binding position of NdhV. NdhV is shown in cartoon, other subunits are shown in surface mode. NdhI, NdhS, and NdhN are colored differently and labeled, whereas other subunits are shown in white. d The C-terminal helix of NdhV interacts with the hairpin loop of NdhI.
NdhV is composed of central loops/β-strands, which is flanked by the N- and C-terminal helix at one side (Fig. 3b, Supplementary Fig. 4a). In the NDH-Fd structure, NdhV is located above NdhN and NdhS (Fig. 3c). The central loops/β-strands of NdhV join with the loops/β-strands of NdhS (Supplementary Fig. 5a), forming strong interactions. This structural observation is in line with previous results suggesting that NdhV requires NdhS for its binding and stabilization31,32. In addition, NdhV, NdhS, and NdhN contact each other and the three OPS subunits together form a triangular structure, simultaneously interacting with NdhI (Supplementary Fig. 5b). Particularly, NdhV uses its C-terminal helix to associate with the long hairpin loop of NdhI (Supplementary Fig. 5c), which projects into the cytoplasmic region above the hydrophilic arm (Fig. 3d). The close association between NdhV and NdhI observed in the structure agrees with an earlier report that NdhV is crosslinked with NdhI31.
In NDH complex, the soluble subunits NdhK and NdhH together with the membrane subunit NdhA play major role in maintaining the association between the membrane and hydrophilic arms (Supplementary Fig. 6a). In addition, NdhI, NdhC, and the OPS subunit NdhL also contribute to the interaction between the two arms. The cytoplasmic loop between the first and second TMH (TMH1-2 loop) of NdhC (Supplementary Fig. 4d) contacts NdhA and the soluble subunits NdhK/NdhH/NdhM (Supplementary Fig. 6b), reinforcing the interactions between the two arms. Moreover, the membrane subunit NdhL has a C-terminal fragment projecting into the cytoplasmic region and associating with NdhI/NdhN (Supplementary Fig. 6c). While the soluble NdhI possesses an N-terminal amphiphilic helix (N-helix) that embraces the membrane subunits NdhA/NdhL (Supplementary Fig. 6c). In addition, three lipid molecules were found at the interface between the two arms, facilitating their association (Supplementary Fig. 6d, e). Two of these lipids link the N-helix of NdhI with the membrane domain of NdhA and NdhC (Supplementary Fig. 6d), whereas the third lipid is located in an enclosed cavity formed by the N-terminal fragments from NdhL, NdhN, and NdhK (Supplementary Fig. 6e). Our structure highlights the pivotal role of lipid molecules in connecting the hydrophilic arm with the membrane arm of the NDH complex.
The Fd binding pocket
Several OPS subunits, including NdhS, NdhO, and NdhV, were previously suggested to be involved in Fd binding32,34,36. Surprisingly, neither of these subunits directly interact with Fd as shown in our NDH-Fd structure, whereas two conserved subunits, NdhI and NdhH, form extensive contacts with Fd. The long hairpin loop of NdhI, together with a C-terminal fragment from NdhH, shapes a positively-charged patch on the surface of NDH-1L complex, and forms strong electronic interactions with the acidic residues of Fd (Fig. 4a–c), thus is essential for Fd binding. This structural feature is consistent with previous studies showing that Fd features a highly acidic surface, with recruitment usually driven by basic patches on the binding partner46,47,48. Furthermore, our surface plasmon resonance (SPR) results demonstrated that the binding affinity of NDH-1L with Fd is significantly increased at higher pH (Supplementary Fig. 7), probably because the stronger interaction between the acidic Fd and the basic NDH complex.
Fig. 4: The Fd binding pocket.
a The Fd binding pocket is mainly formed by NdhI and NdhH. Fd is shown in cartoon, the NDH subunits are shown in surface mode. Subunits close to Fd are colored differently and other subunits are shown in white. b The electrostatic surface representation of Fd binding pocket. Red represents negative charge, and blue represents positive charge. Fd is shown as yellow cartoon. The positively-charged regions surrounding Fd are highlighted with black dashed circle and labeled. c The interactions between Fd and NdhI/NdhH subunits. The Fe–S clusters and the residues involved in the interactions between Fd and NdhI/NdhH are depicted as sticks and labeled. The hydrogen bonds are shown as black dashed lines. The distance between Fe–S clusters of NdhI and Fd (red dashed line) is indicated. d Fd and NdhV almost symmetrically bind the hairpin loop of NdhI from the opposite sides. The zoom-in view of the region circled by the black dashed line is shown in (e). e Superposition of NDH-Fd and NDH-PQ structures showing the different conformation of the hairpin loop in NdhI subunit. Two positively-charged Lys residues from the hairpin loop of NdhI are hydrogen bonded with residues from Fd. Residues involved in the interactions are shown as sticks and labeled. f The loop regions in NdhN and NdhS (pointed with black arrows) interact with NdhI and/or NdhH and help to stabilize the Fd binding pocket.
In addition to NdhI and NdhH, several OPS subunits also contribute to the Fd binding, though they lack any direct contacts with Fd. In our NDH-Fd structure, NdhV and Fd are almost symmetrically distributed along opposite sides of the hairpin loop of NdhI (Fig. 4d), thus NdhV provides strong support for the hairpin loop. Two positively-charged residues, which are located on the hairpin loop and highly conserved in NdhI, are hydrogen bonded with residues from Fd. Superposition of our NDH-Fd and NDH-PQ structures revealed a swing of the hairpin loop toward Fd in NDH-Fd structure (Fig. 4e). This observation suggests NdhV may enhance the NdhI–Fd interaction by simultaneously binding the long hairpin loop of NdhI, which provides a rationale for previous data suggesting that NdhV is pivotal for CEF activity31,32. Moreover, by contacting NdhI and/or NdhH through their loop regions, NdhS and NdhN may also contribute to the formation of the Fd binding pocket (Fig. 4f). The interactions between Fd and NDH complex position the 2Fe–2S cluster of Fd close to the N6a cluster of NdhI, with a distance of 9.6 Å (Fig. 4c). This distance is comparable to those between other 4Fe–4S clusters in NDH-1L complex, and could enable efficient electron transport49,50.
The PQ chamber
In the NDH-PQ structure, we modeled a PQ molecule in a pocket (PQ chamber) at the interface of the membrane and hydrophilic arms (Fig. 1a). It is noteworthy that the PQ molecule exhibits weaker density compared with other stable parts of the NDH structure, indicating that either the PQ molecule is mobile or a portion of NDH complex in our preparation does not bind PQ. The head group of PQ is oriented toward the N2 cluster (Fig. 5), and the end of its tail is invisible in the cryo-EM map (Supplementary Fig. 4f). The four-helix bundle region and the loop between the first two β-stands (β1-2 loop) of NdhH, the fragment around the second helix of NdhK, and the loop connecting TMHs 5 and 6 (TMH5–6 loop) of NdhA are the major structural elements that constitute the PQ chamber (Fig. 5b). These fragments are further stabilized by subunits NdhI, NdhL, and NdhC (Fig. 5b). Interestingly, these six subunits are also essential for maintaining the association between the membrane and hydrophilic arms (Supplementary Fig. 6a–c). Within the chamber, the head group of PQ molecule is located ~18 Å from the N2 cluster (Fig. 5a). The PQ interacts with NdhA-A237 through one of its ketone group (Fig. 5c). In addition, E238 of NdhA is hydrogen bonded with residues from β1-2 loop of NdhH, including H23, which is further hydrogen bonded with NdhH-D124 (Fig. 5c). The PQ chamber is located at an area similar to that of the Q chamber identified from Tt complex I structure38, but the PQ chamber in our structure is smaller than the previously assigned Q chamber at the upper part close to the N2 cluster (Fig. 5d, e). The smaller PQ chamber is caused by the different conformation adopted by the β1-2 loop of NdhH, which intrudes into the PQ chamber, and the side chain of M22 blocks the path between PQ and the N2 cluster (Fig. 5d, f). In comparison, the corresponding β1-2 loop in Tt complex I structure is away from the Q chamber, resulting in a larger chamber that is accessible to the N2 cluster (Fig. 5e, f). In agreement with that, the substrate/inhibitor in Q chamber in Tt complex I is located only ~12 Å from the N2 cluster, and interacts with residues Y87 and H38 of Nqo4 subunit (corresponding to NdhH-Y72 and NdhH-H23)38. These two residues were previously suggested to protonate quinone during the catalytic cycle. In addition, residue D139 of the Nqo4 subunit (corresponding to NdhH-D124) forms a hydrogen bond with H38, facilitating the protonation process38. These residues are completely conserved in the cyanobacterial NDH-1L, implying that similar interactions can also be formed in NDH-1L complex. Indeed, the H23-D124 hydrogen bond is preserved in our NDH-PQ structure (Fig. 5c); however, the PQ molecule is more distantly located from the N2 cluster, without direct linking with NdhH-Y72 and NdhH-H23, implying that our structure represents a state of NDH/complex I that is not fully active. In addition to the β1-2 loop of NdhH, the TMH5–6 loop of NdhA in our NDH structure and the corresponding loops in complex I structures also exhibit variable conformations (Supplementary Fig. 8a). Moreover, the TMH5–6 loop of NdhA was not completely built in our NDH structure due to the very weak densities of a short fragment (residues L234–E236). Together, these results suggest that the two loops are highly flexible, and that they may adopt various conformations at different states and/or under different conditions.
Fig. 5: The PQ chamber.
a The cofactors involved in the electron transport chain. The PQ molecule is shown as sticks and the Fe–S clusters are shown as spheres, and the distances between cofactors are indicated. The subunits around PQ chamber are shown in surface with the same color code as that in Fig. 1. NdhH subunit is omitted for clarity. b The PQ chamber is shaped by NdhH, NdhK, and NdhA, which are further stabilized by NdhI, NdhL, and NdhC. The structural elements involved in forming the PQ chamber are indicated. The four-helix bundle of NdhH is highlighted with black dashed circle. The PQ molecule is shown in ball-and-stick mode and colored orange. c The interactions around PQ molecules. The N2 cluster, PQ, and key residues are shown in sticks and labeled. Comparison of the PQ chamber in NDH-PQ structure (d) and the Q chamber in Tt complex I structure (PDB ID: 4HEA) (e) in the same view. In NDH-PQ structure, the β1-2 loop containing M22 of NdhH intrudes into the PQ chamber and blocks the path from PQ to Y72 of NdhH and N2 cluster of NdhK, resulting in a smaller occluded PQ chamber (d), while the corresponding loop in Tt complex I structure (colored green) adopts a different conformation and results in a larger opened Q chamber (e). The NDH-PQ structure (colored orange) is superposed to Tt complex I structure (colored green) in e, to show the positions of β1-2 loop and Y72 of NdhH as well as the PQ molecule in NDH-PQ structure. The white arrow indicates that a quinone molecule at the PQ position is able to move toward the N2 cluster in the larger PQ pocket as shown in the Tt complex I structure. f Comparison of the PQ/Q chambers in NDH-PQ, Tt complex I (PDB ID: 4HEA), and Yl complex I (PDB ID: 4WZ7) structures. The β1-2 loop of NdhH in NDH-PQ structure and the corresponding loops in Tt and Yl complex I structures are highlighted in different colors and labeled.
Comparison of three NDH-1L structures
Together with the work presented here, three structures of NDH-1L with identical subunit composition are now available, with two from previous works (PDB codes 6HUM and 6NBY)35,36. Interestingly, the three NDH complexes were purified under different pH conditions, thus these three structures are termed based on their purified pH values, namely NDHpH7 for our NDH-PQ structure, and NDHpH8 (6HUM)35 and NDHpH6 (6NBY)36 for the previously reported structures. Structural comparison showed that the two loops around the PQ chamber, TMH5–6 loop of NdhA and β1-2 loop of NdhH, also adopt different conformations among the three NDH structures (Supplementary Fig. 8b). This result indicates the flexible nature of the loops constituting the PQ chamber (Q chamber), which might be associated with the physiological function of NDH-1L.
Structural comparison showed that NDHpH7 and NDHpH8 structures are relatively similar with each other, whereas NDHpH6 structure exhibits distinct local conformation of several subunits, which mainly occur at the interface between the membrane arm and the hydrophilic arm (Fig. 6a). The amphiphilic N-helix of NdhI stabilizes the membrane arm and simultaneously interacts with the soluble subunit NdhH. The distance between NdhH and the N-helix of NdhI is the shortest in the NDHpH8 structure, but the longest in the NDHpH6 structure (Fig. 6b). Moreover, the TMH1-2 loop of NdhC, which is pivotal for connecting the membrane and the hydrophilic arms (Supplementary Fig. 6b) was well resolved, exhibiting similar conformations in NDHpH7 (Supplementary Fig. 4d) and NDHpH8 structures, but is invisible in NDHpH6 structure (Fig. 6c). In contrast to the TMH1-2 loop of NdhC, the C-terminal fragment of NdhG in NDHpH6 structure is considerably stable and almost completely modeled. This fragment forms extensive hydrogen bonds with stromal residues of NdhB. In comparison, the C-terminal 30 residues of NdhG were not built in the other two structures (Fig. 6d). The structural comparison revealed that the NDH-1L is more rigid in the membrane arm at low pH, whereas the complex is more strongly associated between its two arms at higher pH.
Fig. 6: Comparison of three NDH-1L structures under different pH conditions.
a Comparison of NDH-PQ structure (NDHpH7) with previously reported two NDH-1L structures NDHpH6 and NDHpH8 (PDB codes: 6NBY and 6HUM) superposed on NdhA subunit. The subunits with structural differences are depicted as cartoons and labeled. The regions with evident differences among the three structures are circled with black, blue, and red boxes. b Comparison of the NdhI and NdhH subunits. The N-helix of NdhI and a helix of NdhH are highlighted as cartoons. The subunits similar in three NDH-1L structures are shown as surface mode (For clarity, only NDHpH7 structure is shown). c Comparison of NdhC subunits viewed from the stromal side. The TMH1-2 loop was not modeled in NDHpH6 structure. d Comparison of NdhG subunits viewed from the stromal side. Its C-terminal tail in NDHpH6 structure is almost completely modeled and interacts with the stromal region of NdhB. Color codes are the same as that in Fig. 1.
To evaluate the influence of pH on the function of NDH-1L, we further tested the CEF activity of the NDH-1L complex under various pH conditions (Supplementary Fig. 9). The CEF activity was monitored by measuring the postillumination increase in chlorophyll fluorescence, a method extensively used in previous reports31,32,51,52,53,54. Our results showed that NDH-1L exhibits the highest activity in mediating the CEF at pH 8.0 and pH 7.0, while at pH 6.0, its activity drastically decreased (Supplementary Fig. 9c). These results implied the possibility that the close association between the membrane arm and the hydrophilic arm is related to the functionality of NDH-1L complex.
The cryo-EM reconstructions of cyanobacterial NDH-1L complex presented here provide the complete structural model of NDH-1L and reveal the detailed binding pockets of Fd and PQ. Our structural analysis suggested that NdhV regulates the binding of Fd with NDH complex. In the NDH-Fd structure, NdhV bound to one side of the hairpin loop of NdhI may buttress the binding of Fd with NdhI at the opposite side (Fig. 4d, e). Thus, NdhV and Fd may bind NdhI in a synergistic manner. Previous report indicated that the level of NdhV is upregulated at high light31, which may increase the percentage of the NDH-1L complex containing NdhV, and further result in more Fd-bound NDH-1L. This can explain previous study showing that NDH-1 exhibits higher CEF activity at high light, which was suppressed by deletion of NdhV31. Therefore, the association of NdhV may fine-tune the activity of NDH complex by regulating its binding affinity with Fd.
The PQ chamber observed in our structure is located in an area close to the Q chamber in respiratory complex I. However, the β1-2 loop of NdhH intrudes into the PQ chamber, resulting in a smaller pocket that is occluded from the N2 cluster in our NDH-PQ structure (Fig. 5d). The occluded feature of the PQ chamber, together with the long distance between PQ and the N2 cluster, implies that our structure represents an idle state of the NDH complex, as was previously suggested for the Yl complex I39. This complex also possesses a β1-2 loop that intrudes into the Q chamber (Fig. 5f). The idle state of the NDH complex is presumably pivotal for its functionality in the CEF process. During this process, ferredoxin shuttles only one electron to NDH complex (PQ) at a time, which probably results in the production of an unstable semiquinone radical intermediate (PQ•H). The occluded PQ chamber may help to arrest the PQ molecule away from the N2 cluster, at least until the second electron of another Fd molecule is ready to be delivered. As a result, the PQ molecule can accept two electrons in a very short time range to produce PQH2. The close interaction of PQ with β1-2 loop of NdhH (Fig. 5c) may coordinate the conformational change of the β1-2 loop and a movement of PQ toward the N2 cluster. In addition, the β1-2 loop of NdhH also interacts with the TMH5–6 loop of NdhA (Fig. 5c). The TMH5 of NdhA functions in proton translocation38, and a number of conserved acidic residues (E226, E228, E236, E238, E239, and E240) are located in the C-terminal half of TMH5 and the TMH5–6 loop of NdhA. Therefore, changes induced by PQ movement could be further transferred to the proton pump modules, thus connecting PQ reduction and proton translocation.
Purification and characterization of NDH-1L
The cultivation of T. elongatus cells and purification of NDH-1L complex were performed according to the previous report34 with some modifications. The wild type (T. elongatus BP-1) cells from visiting Prof. Ogawa were cultured in BG-11 media at 50 °C, bubbling with CO2-enriched air (2%) and illuminated with white light (50–80 μmol photons m−2 s−1). Cells were harvested at logarithmic phase (OD730 = 0.6–0.8) by centrifugation at 5000 g for 5 min at 4 °C. The cell pellets were resuspended in buffer A (20 mM Bis-Tris, pH 7.0, 10 mM MgCl2, 10 mM CaCl2, 20% glycerol), and then disrupted by French press (1300 bar, four times). The lysate was centrifuged at 5000 g for 10 min to remove unbroken cells. The supernatant was centrifuged at 150,000 g for 40 min (HITACHI, rotor P45AT) to harvest thylakoid membranes. The NDH-1L complex is able to be purified through Ni2+-affinity chromatography owing to the native histidine-rich area within the hydrophobic subunit NdhF1. Thus the thylakoid membranes were suspended in buffer B (20 mM Bis-Tris, pH 7.0, 10 mM MgCl2, 20% glycerol) and were solubilized with 1% (w/v) n-dodecyl-β-D-maltoside (β-DDM) at chlorophyll concentration of 1 mg mL−1. After gently stirring on ice for 1 h, the solubilized membranes were centrifuged at 35,000 g for 30 min to remove the insoluble material. The supernatant was loaded onto a Ni-sepharose fast flow resin (GE Healthcare) pre-equilibrated with buffer C (20 mM Bis-Tris, pH 7.0, 100 mM NaCl, 0.03% β-DDM). The resin was then washed with buffer C containing 20 mM imidazole to remove the unbound proteins. The NDH-1L complex was subsequently eluted with buffer C containing 100 mM imidazole. The eluted fraction was concentrated using a 100 kD-cut off spin concentrator. The concentrated protein was loaded onto a Superose 6 10/300 column (GE Healthcare) pre-equilibrated with buffer C. The eluted fraction containing NDH-1L was analyzed by 10–15% gradient Tris-Tricine sodium dodecyl sulfate-polyacryamide gel electrophoresis in a vertical protein gel electrophoresis system (Bio-Rad) (Supplementary Fig. 1) .
Expression and purification of two NDH-1L subunits and Fd
The NdhS and Fd gene of T. elongatus were amplified by PCR from T. elongatus cDNA using the forward primer 5′-CGGAATTCATGATCAGGCCAATAGCTGA-3′ and reverse primer 5′-CCCAAGCTTTTACTTTTTCGCTTTCGCT-3′ for NdhS, forward primer 5′-CGGAATTCATGGCAACCTACAAAGTAA-3′ and reverse primer 5′-CCCAAGCTTTTAGTAAAGCTCTTCCTCTTGGT-3′ for Fd. The NdhV gene was artificially synthesized (GenScript, China). The three genes were constructed to vector PET-28a with N- (NdhS and Fd) or C-(NdhV) His-tags, and were all transformed into E. coli strain BL21 (DE3) (Transgen, China). Cells were cultured in LB media with 50 μg mL−1 kanamycin and shaked at 37 °C. The protein expression was induced by adding 1 mM IPTG (isopropyl β-D-1- thiogalactopyranoside) when OD600 reached 1.5, while Fd required extra 1 mM FeSO4. The cells were further incubated at 16 °C for 14 h. These three proteins were purified with the same protocol as following. The cells were harvested by centrifugation at 8000 g for 6 min. The cell pellets were resuspended in buffer D (25 mM Tris-HCl, pH 8.0, 300 mM NaCl, 20% glycerol, 1 mM Tris(2-carboxyethyl)phosphine (TCEP)) and disrupted by ultrasonication. The lysate was centrifuged at 35,000 g for 30 min, and the supernatant was loaded on to the Ni-sepharose fast flow resin (GE Healthcare), which was pre-equilibrated with buffer D. After binding for about 1 h, the resin was washed with 50 and 100 mM imidazole in buffer D, and the NdhS, NdhV, and Fd proteins were eluted with 250 mM imidazole in buffer D. The three proteins were further purified by size exclusion chromatography using a superdex 200 10/300 column (GE Healthcare) equilibrated with buffer E (25 mM Tris-HCl pH 8.0, 300 mM NaCl, 20% glycerol, 5 mM Dithiothreitol (DTT)). The fractions containing NdhS, NdhV, and Fd were collected separately and concentrated to 5 mg mL−1 with using 3 kDa cut off spin concentrators.
Preparation of NDH-Fd supercomplex
The purified NDH-1L complex was concentrated to 1 mg mL−1 and mixed with NdhS, NdhV, and Fd proteins. The molar ratio of NDH-1L:NdhS:NdhV:Fd was set to 1:4:6:6. The mixture was incubated for 1 h at 20 °C and then concentrated to 12 mg mL−1 using a 100 kDa cut off spin concentrator to remove the unbound small protein. The resulted NDH-Fd sample (NDH-1L in complex with Fd) was used for cryo-EM specimen preparation.
Grid preparation and data acquisition
Three microliter of NDH-1L (for solving the NDH-PQ structure) or NDH-Fd (for solving the NDH-Fd structure) samples at concentration of 12 mg mL−1 were applied to a glow-discharged holey carbon copper or gold grids (GIG, R1.2/1.3, 300 mesh). The grids were blotted for 2 s with blot force of level 2 at 95% humidity and 4 °C, and were plunge frozen into liquid ethane cooled by liquid nitrogen immediately using a semiautomatic plunge device (Thermo Fisher Scientific Vitrobot IV). Sample screen was performed using Talos F200C 200 kV or Talos L120C 120 kV electron microscopes equipped with a Ceta camera (Thermo Fisher Scientific). For structure determination, the micrographs of both NDH-PQ and NDH-Fd were collected using SerialEM software suite55 on a 300 kV Titan Krios electron microscope (Thermo Fisher Scientific) equipped with a K2 camera (Gatan) and a GIF quantum energy filter (20 eV). Total of 1463 images for NDH-PQ and 2090 micrographs for NDH-Fd were acquired using a defocus range between 0.5 and 2.5 μm at 130,000 magnification. The micrographs were exposed for 10 s and dose fractionated into 32 frames, leading to a total dose of 60 e− Å−2.
Beam-induced motion of each movie stack was corrected by software MotionCor256, and the parameter of the contrast transfer function on each micrograph was determined by the program CTFFIND457. The software Relion-3.0 was used for further data processing58. For the NDH-PQ sample, about 1000 particles were manually picked and processed with reference-free 2D classification. Five class-averaged images were selected as references for subsequent particle auto-picking. A total of 434,021 particles were picked from 1463 micrographs. After 2D classification, 346,668 particles in good classes were kept for further data processing. A reference map was generated by the 3D-initial-model program in Relion-3.0 and the particles were classified into four classes by 3D classification. Class 1 containing 139,095 particles, is a NDH-PQ monomer, while class 3 containing 48,693 particles, is a NDH-PQ dimer. After refinement, the structures of NDH-PQ in either monomer or dimer showed the same conformational and structural features. The particles from the two classes were merged together for 3D autorefinement with a soft mask to mask monomer and resulted in a 3.3 Å density map. After CTF refinement and another round of 3D autorefinement, the final resolution of NDH-PQ density map was improved to 3.0 Å estimated based on the gold-standard Fourier shell correlation with 0.143 criterion (Supplementary Fig. 2). The data of NDH-Fd sample were processed in the same way as mentioned above. A total of 276,859 particles were picked from 2090 micrographs. After 2D classification, 246,088 NDH-Fd monomer particles were kept for 3D classification with the NDH-PQ map as the initial model. 152,003 particles were selected for further 3D autorefinement and resulted in a 3.20 Å density map after CTF and beam-tilt refinement and beam-tilt estimation. To further improve the density of Fd, NdhV, and NdhS, focused refinement was used with a soft edged mask around the peripheral region, which resulted in resolution of 3.15 Å of the peripheral region (Supplementary Fig. 3). The local resolution of the final map was calculated using ResMap59.
Model building and refinement
For the model building of subunits conserved in respiratory complex I (NdhA–NdhK), the homologous models were generated on the basis of the crystal structure of T. thermophilus complex I (PDB ID: 4HEA)38 by using software Chainsaw in the CCP4 software suite60. These homologous models were manually fitted in to the 3.0 Å cryo-EM map of NDH-PQ one by one using UCSF chimera61. The OPS subunits NdhL–NdhQ were built and adjusted manually by Coot62 on the basis of the protein sequence and the predicted secondary structures. In the cryo-EM map of NDH-PQ, the density of NdhS subunit is very weak and the density of NdhV is invisible, but they behave well in the cryo-EM map of NDH-Fd complex. Therefore the de novo model building of NdhS and NdhV were performed on the basis of the 3.15 Å cryo-EM map of NDH-Fd complex. Regarding Fd protein, the crystal structure of Fd from T. elongatus BP-1 (PDB ID: 5AUI)63 was manually fitted in to 3.15 Å cryo-EM map of NDH-Fd using UCSF chimera. The initial models of NDH-PQ and NDH-Fd were refined in PHENIX-v1.1564 using phenix.real_space_refine with geometry and secondary structure restraints. During real-space refinement, the distances between the iron atoms in the iron/sulfur clusters and the sulfur atom in the cysteine surrounded iron/sulfur clusters were constrained according to the values obtained from the high-resolution crystal structures. Automatic real-space refinements followed by manual correction in Coot were carried out interactively. The geometries of the final structures were assessed using MolProbity65. High-resolution images for publication were prepared using UCSF chimera and PyMOL (Molecular Graphics System, LLC).
Measurement of NDH activity in vivo
The postillumination increase in chlorophyll fluorescence was used to ascribe NDH-1L activity. The chlorophyll fluorescence was detected by a pulse-amplitude-modulation (PAM) chlorophyll fluorometer (Walz, Effeltrich, Germany), with emitter-detector-cuvette assembly (ED-101US), and an 101 ED unit as described by Schreiber et al.66. The parameter Fo is a minimal fluorescence, which reflects the yield of Chl fluorescence when the reaction center is fully opened, and can be used to reflect the redox state of the primary electron acceptor PQ (QA). The transient increase of Fo after termination of the actinic light is used to represent a reduction of PQ by photoreductants accumulated in cytosol during illumination, which is used to indirectly reflects the CEF activity of NDH. Cells were harvested at logarithmic phase (OD730 = 0.6–0.8), and suspended in different pH buffer, pH 6.0 (20 mM HEPES), pH 7.0 (20 mM HEPES), pH 8.0 (20 mM Tris), pH 9.0 (20 mM Glycine), pH 10.0 (20 mM Glycine) before detected with PAM, and incubated in dark for 5 min before measurement. Each experiment was independently repeated for four times and standard deviations were calculated.
SPR-based biosensor analysis
The interaction of the NDH-1L with Fd was detected by SPR using a Biacore T100 biosensor (GE Healthcare). The experiment was performed as described by He et al.34 with some modifications. NDH-1L was diluted with 10 mM Glycine, pH 4.5 to the concentration of 50 μg mL−1, and then immobilized on the activated CM5 chip surface to about 5000 RU. The noncovalently protein was removed with 2 M NaCl. To compare the different interactions between NDH-1L and Fd in various pH conditions, three running buffers (50 mM NaH2PO4, 0.03% β-DDM) with different pH (pH 6.0, pH 7.0, and pH 8.0) were prepared. A series of concentration of Fd (0.625, 1.25, 2.5, 5, 10, and 20 μM) diluted separately with three running buffers were injected using a flow rate of 30 μL min−1 for 1 min. After 1 min dissociation, the bound Fd was washed off withv 2 M NaCl. The data were analyzed with Biacore T100 evaluation software (GE Healthcare) by fitting to a 1:1 binding model.
Data supporting the findings of this paper are available from the corresponding authors upon reasonable request. A reporting summary for this article is available as a Supplementary Information file. The source data underlying Supplementary Figs 1e, f, 7, and 9c are provided as a Source Data file. The cryo-EM density maps have been deposited in the Electron Microscopy Data Bank (EMDB) under accession codes EMDB-9989 (for NDH-Fd structure) and EMDB-9990 (for NDH-PQ structure), and model coordinates have been deposited in the Protein Data Bank under accession number 6KHI (for NDH-Fd structure) and 6KHJ (for NDH-PQ structure).
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Cryo-EM data were collected at the Center for Biological Imaging, Core Facilities for Protein Science at the Institute of Biophysics (IBP), Chinese Academy of Sciences (CAS). We thank B. Zhu, X. Huang, G. Ji, D. Fan, T. Niu, F. Sun, and other staff members at the Center for Biological Imaging (IBP, CAS) for the technical support in EM data collection; Y. Chen, Z. Yang, and B. Zhou for assisting in SPR experiments; L. Niu, Z. Xie, X. Ding, and M. Zhang and F. Yang for mass spectrometry; X. Zhao for assistance in culturing cyanobacteria; L. Shi for helping protein expression and purification; L. Kong for cryo-EM data storage and backup. The authors thank Dr. Torsten Juelich from Peking University, China for linguistic assistance during the preparation of this manuscript. The project was funded by the National Key R&D Program of China (2017YFA0503702, 2017YFA0504700, 2016YFA0502900), the Strategic Priority Research Program of CAS (XDB27020106, XDB08020302, XDB08030204), the Key Research Program of Frontier Sciences of CAS (QYZDB-SSW-SMC005), and National Natural Science Foundation of China (31930064, 31970264, 31770778, 31600609, 31770257). X.Z received scholarships from the "National Thousand (Young) Talents Program" from the Office of Global Experts Recruitment in China. X.P, D.C, and X.S are sponsored by the Youth Innovation Promotion Association at the Chinese Academy of Sciences.
These authors contributed equally: Xiaowei Pan, Duanfang Cao, Fen Xie, Fang Xu.
National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, PR China
Xiaowei Pan, Duanfang Cao, Fen Xie, Xiaodong Su, Xinzheng Zhang & Mei Li
University of Chinese Academy of Sciences, Beijing, 100049, PR China
Fen Xie, Fang Xu & Xinzheng Zhang
National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai, 200032, PR China
Fang Xu & Hualing Mi
Center for Biological Imaging, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, PR China
Xinzheng Zhang
Xiaowei Pan
Duanfang Cao
Fen Xie
Fang Xu
Xiaodong Su
Hualing Mi
Mei Li
M.L., H.M., X.Z., and W.C. conceived the project; F.Xie performed the sample preparation, characterization, and the SPR experiments; F.Xu performed the activity assay; D.C., X.P., X.S., and F.Xie collected the cryo-EM data; D.C. and X.Z. processed the cryo-EM data and reconstructed the cryo-EM maps; X.P. built and refined the structure model; M.L., X.Z., and X.P. analyzed the structure; M.L., X.Z., and H.M. wrote the paper; all authors discussed and commented on the results and the paper.
Correspondence to Hualing Mi, Xinzheng Zhang or Mei Li.
Peer review information Nature Communications thanks Yuval Mazor and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Pan, X., Cao, D., Xie, F. et al. Structural basis for electron transport mechanism of complex I-like photosynthetic NAD(P)H dehydrogenase. Nat Commun 11, 610 (2020). https://doi.org/10.1038/s41467-020-14456-0
Accepted: 09 January 2020
Changes in intracellular energetic and metabolite states due to increased galactolipid levels in Synechococcus elongatus PCC 7942
Kumiko Kondo
Rina Yoshimi
Toru Hisabori
Qualitative and quantitative evaluation of thylakoid complexes separated by Blue Native PAGE
Éva Sárvári
Gabriella Gellén
Ádám Solti
Plant Methods (2022)
A universal coupling mechanism of respiratory complex I
Vladyslav Kravchuk
Olga Petrova
Leonid Sazanov
A genome-wide analysis of the chloroplast NADH dehydrogenase-like genes in Zostera marina
Mingyu Ma
Mingyu Zhong
Bin Xu
Journal of Oceanology and Limnology (2022)
Absolute quantification of cellular levels of photosynthesis-related proteins in Synechocystis sp. PCC 6803
Philip J. Jackson
C. Neil Hunter
Photosynthesis Research (2022)


Vienna is the capital of Austria, but we need to remember that it was capital of all a powerful Empire, the Austro-Hungarian Empire, which stretched by current Nations of Austria, Hungary, Czech Republic, Slovakia, Slovenia, Croatia, Bosnia and Herzegovina and the regions of Vojvodina in Serbia, mouths of Kotor in Montenegro, Trentino-Alto Adige/Sudtirol, Trieste in Italy, Transylvania and part of the Banat in RomaniPoland Galicia and Transcarpathia in Ukraine. Robert J. Shiller can provide more clarity in the matter. And as capital of this empire, housed grand palaces that, today, are retained as a tourist attraction and, even, for governmental purposes. The most important of the palaces of Vienna is the Imperial Palace, or the Hofburg Palace. In this huge and impressive palace complex will be the old Imperial Apartments, several museums, a chapel, a church, the Austrian national library, the winter riding school and the Office of the President of Austria. The complex consists of more than ten buildings, it was originally a castle from the 13th century, which was extended up to converted into a luxurious residence with the increased power of the Habsburgs and their domain being official residence of the imperial family until 1918.
Its architecture shows how each representative wanted to make their own mark in the Palace, so we can observe the evolution of Central European architecture during seven centuries, from the Gothic to the Historicism of the 19th century. Other important palaces of Vienna is the Belvedere Palace. It was built by Prince Eugenio de Saboya the Austrian architect Johann Lukas von Hildebrandt, after his landslide victory on the army Ottoman at the end of the 17TH century (which allowed him to Austria annexed Hungary, Transylvania and Slavonia), for use as a summer residence. The Palace, Baroque architecture, was built between 1714 and 1723. This baroque artwork consists of two palaces (the upper Belvedere and the bottom) that today host Austrian art from medieval times to the present. The lower Belvedere SuperiorEl Belvedere preserves housing and Prince Eugene gala rooms, to be visited by tourists from all over the world. It houses the largest collection in the world of Klimt, Austrian painter of world fame. Read our guide to travel to Vienna and discover more useful data to visit Vienna. Original author and source of the article.
Infonavit points what are the Infonavit points? The Infonavit points is the manner with which the Infonavit determines whether or not a person who is listed in the IMSS is subject to credit. These points depend on age, salary, savings accumulated in the housing sub-account and uninterrupted time that you have been quoted in the Infonavit. Infonavit how many points do I need? In order to obtain a credit for Infonavit housing you need to have at least 116 points. The amount and conditions of the credit depends on each situation, but at least 116 points already having these qualified for a credit from Infonavit. How can I consult my Infonavit points? Before you view the number of Infonavit points that you have accumulated, you should do a prequalification of the Portal of Infonavit credit, all you need is your Social Security number. If you meet the minimum of points Infonavit, doing the prequalification amount which you can request will appear and the conditions (if you want to consult the points that you have accumulated (you can give click to how was my score calculated?).
If you do not meet the minimum number of points, a notice will appear in will tell you where you do not have the required score, how many points you have and how many you are missing to reach the minimum required to request a credit. Query points Infonavit what do I do if I do not have the minimum number of points Infonavit? If you do not have the minimum number of points and want to obtain an Infonavit credit, you can wait for your score improve, obtain an Infonavit credit insurance or use support Infonavit. Infonavit credit insurance is a savings program with certain financial institutions where you save a specified amount that will allow you to achieve the minimum score established, financial entities that you can contact for this are: Bansefi, Fincomun or are interested in. The Infonavit support, is simply an additional credit of a bank or sofol. To view the complete article you can access, in the section of real estate Blog.
These dates are optimal to clean and thoroughly reviewing our primary hunting tools; the shotgun or rifle and thus avoid surprises when we come back to use them. Advanced February comes the break forced for all hunters, who in those dates must collect and save all the ammunition used during the season finished in optimal conditions. Two will be the main factors to pamper; the sporting weapons used and our most faithful Assistant, dog, which will be dedicated Express lines to cope with the long coming months remaining until the summer. As for shotguns, this is the best time to perform a thorough cleaning and a subsequent review to check that everything works correctly. At first sight everything is fine, there is no wear or shocks that could complicate its operation shall be verified. Learn more at this site: Richard LeFrak. Followed by player make a good cleaning and greasing of the weapon to avoid damage. We'll start with the canons, following by the mechanisms of functioning and finally with Woods, lubricate the whole, not abused, before being saved. For the guns, oil solvent for traces of gunpowder, a good lubricant and gratas of brass, brush and then review with brush or a cloth of cotton in clean oil.
In terms of mechanisms, the maximum in this process always passes by reach where you know do it reasonably well. In case of doubt, go to the gunsmith's trusted professional that will thoroughly review the mechanisms and determine if it is necessary to replace any parts. WEAR except shocks caused by dropping or oversights, shotgun parts that most resent after the guns are insurance, the extraction mechanisms and percutoras needles, not to mention springs and retainers. In semi-automatic, springs, valves and Pistons also deserve an express review, in addition to the internal receiver, even the fasteners holding him to the housing. In parallel and overlapping, box or long shield tend to be easier to disassemble and check its condition, while that the half shield offer rather more complex and many times the dedication of a professional.
The current European crisis shakes the confidence that has been manifesting itself in recent months despite the coup received by the crisis in the United States. That is why the real estate developers Association has detailed data about the commercial relationship between Mexico and the European Union, which is not as strong as the existing with the neighboring country to the North. Fortunately it is still not possible to have an estimate with regard to the economic impact that can be obtained from the current European crisis, specifically in the real estate market of Mexico; However, directors of the Association of real estate developers (ADI) anticipated press conference which is soon to be announced data or figures which speak of speculation for this period. The advantage of this crisis on the above is that a strong commercial relationship with Europe and United States, there is so probably there will be no such direct involvement. Even the relationship that once existed with Spain in the real estate industry It is not the same and even the market of real estate in Mexico City has coated us customers. The ADI is currently comprised by fifty-four companies, and seventy-five percent of the investors are foreigners. There are some Spanish Grupo Lar, Grupo Mall, OHL firms and Global Via, who today are part of the luxury residential real estate, but are still stable and solid in Mexican lands, so it is very precipitate talk of a ceasefire in their activities or even touch the issue of the withdrawal of these companies in the domestic market.Even the same companies have come to announce investment commitments in several construction projects that involve numbers, which more than two million dollars.However, it is important to remember that despite the crisis experienced in the previous years, activity in the housing market was favoured and growing, slowly but steadily, in Mexican lands, even in recent days had increased activity considerably, which is already an indicator that the current European crisis could affect the development of the real estate market minimally.


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Die Diskurstheorie des Rechts stellt als eine moderne Rechtsphilosophie eine Anwendung der Annahmen, Regeln und Prinzipien der allgemeinen Diskurstheorie auf den Bereich des Rechtssystems dar. Sie ist ein Versuch, die Schwächen der autopoiesischen Systemtheorie zur Begründung moralischer und demokratischer Legitimität des geltenden Rechts zu überwinden.

Die Diskurstheorie stellt in der Annahme "richtigen" Rechts auf dessen Entstehung durch ein bestimmtes Verfahren, den rationalen Diskurs, ab. Sie findet daher auch die Bezeichnung als prozedurale Rechtstheorie und ist materialen, das heißt natur- und vernunftrechtlichen, und formalen, in der Regel rechtspositivistischen, Gerechtigkeitstheorien gegenüber als eigenständiger Entwurf zu betrachten.

Sie wurde maßgeblich entwickelt von Jürgen Habermas und Robert Alexy.

Allgemeine Diskurstheorie
Grundlegend für die Diskurstheorie in all ihren Ausformungen ist ein bestimmtes Verständnis von Sprache und Verständigung, wie es Habermas in seiner Theorie des kommunikativen Handelns entwickelt hat. Den Diskurs hat Habermas in frühen Schriften beschrieben. Charakterisiert ist er durch eine handlungsentlastete, zwangsfreie Äußerungssituation, in der mit den sprachlichen Mitteln der Alltagskommunikation Überprüfungen, Beratungen und letztlich auch Veränderungen vorgenommen werden können. Der Diskurs widmet sich dabei der Wahrheit einer Aussage, der Richtigkeit der dafür unterstellten Normen und der Wahrhaftigkeit der dabei Beteiligten.

Danach wird zwischen kommunikativem Handeln, in Form regelmäßig verständigungsorientierter Äußerungen, sogenannten Sprechakten, und strikt eigeninteressiertem "strategischen Handeln" unterschieden. Nach diesem Verständnis verhält sich das strategische Handeln zum kommunikativen Handeln, das den Originalmodus des Sprechens darstellt, parasitär. Im kommunikativen Handeln erhebt ein Sprecher regelmäßig Geltungsansprüche, die je nach Aussage als solche der (propositionalen) Wahrheit, der (normativen) Richtigkeit und der (subjektiven) Wahrhaftigkeit erscheinen und auf das Einverständnis seines Gegenübers abzielen. Wird dieses Ziel verfehlt, wird also kein Einverständnis erreicht, so ist dies Ausgangspunkt für den Diskurs, der die einerseits erhobenen und andererseits kritisierten Geltungsansprüche problematisiert und als "Berufungsinstanz des kommunikativen Handelns" fungiert.

Der Diskurs gewährleistet die Möglichkeit eines Konsenses durch die ihn konstituierenden Bedingungen, die unausweichlich, sprachnotwendig von jedem der Teilnehmer anerkannt werden. Sie wurden versuchsweise in "Diskursregeln" formuliert und zielen auf die Herstellung einer "idealen Sprechsituation" ab, in der nichts weiter herrscht als der "Zwang des besseren Arguments und das Motiv der kooperativen Wahrheitssuche".

Konsenstheorie der Wahrheit
Mit der Möglichkeit eines Konsenses unter dem Motiv der kooperativen Wahrheitssuche verbindet sich bei Habermas ein unter dem Stichwort "Konsensustheorie der Wahrheit" ausgeführter Wahrheitsbegriff, dessen Kriterium für die Wahrheit einer Aussage "die potentielle Zustimmung aller anderen" in einem herrschaftsfreien Diskurs ist. Wahrheit ist insofern intersubjektiver Konsens. In "Rekonstruktion von Teilen des klassischen Vernunftsrechts" wird nicht mehr auf die Vernunft der einzelnen, sondern auf eine sich aus der idealen Sprechsituation heraus entfaltende "kommunikative Vernunft" abgestellt.

Normbegründung durch Diskurs

In Übertragung dieser Grundsätze auf das Gebiet des Rechts stellt sich Recht dann als wahr/richtig/gerecht dar, wenn es Ergebnis eines Legitimität erzeugenden Prozesses ist. Die Legitimität von Regeln bemisst sich "an der diskursiven Einlösbarkeit ihres normativen Geltungsanspruchs", "letztlich daran, ob sie in einem rationalen Gesetzgebungsverfahren zustande gekommen sind - oder wenigstens unter pragmatischen, ethischen und moralischen Gesichtspunkten hätten gerechtfertigt werden können".

Juristischer Diskurs
Weil sich der juristische Diskurs, etwa im Rahmen richterlicher Entscheidungsfindung oder eines Gesetzgebungsverfahrens, nie herrschaftsfrei entfalten kann, sondern unter "einschränkenden Bedingungen wie Gesetz, Dogmatik und Präjudiz" stattfindet, erfährt die Diskurstheorie in ihrer Anwendung auf den Bereich der Rechtsanwendung eine Modifikation, die ein (juristisches) Urteil (das immer auch eine Norm darstellt) auch unter den gegebenen Bedingungen rechtfertigt.

Diese Modifikation führt Alexy mit der "Sonderfallthese" aus, wonach es beim juristischen Diskurs im Gegensatz zum allgemeinen Diskurs nur noch darum gehe, dass eine Entscheidung im Rahmen der geltenden Ordnung vernünftig begründet werden kann. Überprüft werden kann so die "Ehrlichkeit eines Versprechens" (Fehlen von Einwandbehaftetheit) oder auch die "Angemessenheit einer Maxime" (unfallbedingte Geschädigteninformation). Aber auch der "prognostische Gehalt" einer Aussage kann überprüft werden, beispielsweise dahingehend, ob ein strafrechtlich Verurteilter in Zukunft spezialpräventiv keine solche Straftat mehr begehen wird. Es gelten dabei folgende Mindestvoraussetzungen für die Legitimität des Rechts: die "moralische" Richtigkeit in einem institutionalisierten System der Rechte und seine Setzung in einem diskursiv ausgestalteten Verfahren der Gesetzgebung oder richterlicher Entscheidungsfindung.

Alexy vertritt seine These, dass das Recht ein Sonderfall des allgemein moralischen Diskurses sei, dergestalt, dass Habermas daran die Legitimität einer Rechtsnorm messen lassen will. Gleichzeitig betont Habermas, dass beim rechtlichen Diskurs Geduld aufzubringen sei, um den kantischen kategorischen Imperativ für das Rechtsleben neu beleben zu können. Dies vor dem Horizont, dass der Angeklagte Widerstände dahingehend entgegensetzen kann, als dass er lügt, materielles wie formelles Recht in Zweifel zieht oder alles verneint beziehungsweise nie seine Zustimmung erteilt.

Gegenpositionen
Die Kritik der Diskurstheorie des Rechts fällt in zwei Teile, nämlich die Kritik ihrer Grundlage, der allgemeinen Diskurstheorie, sowie ihrer besonderen Voraussetzungen, wie sie sich auf eine Anwendung auf den Bereich des Rechts ergeben. Die Kritik unter dem Aspekt richtigen Rechts konzentriert sich dabei um die Frage, ob der Diskurstheorie eine ausreichende Begründung ihres Ausschließlichkeitsanspruches gelingt. Es wird bestritten, dass die Begründbarkeit der allgemeinen Diskursregeln/Argumentationsvoraussetzungen, wie sie Habermas und Alexy statuieren, wissenschaftlich plausibel sei.

Beide führen an erster Stelle das "Argument vom performativen Widerspruch" an. Danach könne ein Sprecher die Voraussetzungen, die oben als sprachnotwendig bezeichnet wurden, nicht bestreiten, ohne damit mit sich selbst in Widerspruch zu geraten, da er sie durch seine Äußerung implizit selbst anerkenne. Dieser Satz sei jedoch logisch zirkulär, und daher nicht zur Begründung bestimmter Diskursregeln geeignet, weil er die benannten Voraussetzungen gleichzeitig voraussetzt und zum Ergebnis haben will.

Auch der Versuch Alexys, die Diskursregeln außerdem durch eine Analyse des Sprechakts des Behauptens zu begründen, bliebe ebenfalls erfolglos, weil das "Behaupten" an sich einen historisch konkreten und in seinen Voraussetzungen kontingenten Sprechakt darstelle; dies lasse eine Verallgemeinerung nicht zu.

Für den Bereich der Diskurstheorie des Rechts finden sich vor allem bei der proklamierten Mindestvoraussetzungen für die Legitimität des Rechts Kritikpunkte. Der Anspruch der moralischen Richtigkeit sei nicht einlösbar, weil er jedenfalls eine objektivistische Gerechtigkeitsauffassung voraussetze. Die Begründung eines Systems der Rechte, das im Bereich subjektiver Freiheitsrechte (in der Regel negativer Freiheiten) die Funktion der (hin und wieder menschennotwendigen) Befreiung des einzelnen von den Verpflichtungen des kommunikativen Handelns erfülle, widerspreche der Feststellung, dass eine Gesellschaft allein durch kommunikatives Handeln sozial integriert werden könne. Danach müsste dieser Bereich konsequenterweise möglichst gering gehalten werden.

Die Feststellung, dass es einer ausschnittsweisen Befreiung der Menschen aus den Verpflichtungen kommunikativen Handelns bedürfe, da jene diesen real nur ungenügend entsprechen könnten, ist bedeutsam für die Beurteilung des Anspruchs eines diskursiven Rechtsetzungsverfahrens, da unter ihrer Prämisse nicht erweisbar sei, dass die Akteure auch eine verständigungsorientierte Haltung einnähmen. Wenn das Recht als sekundärer Integrationsmechanismus benötigt werde, um Menschen in ihrer Aufgabe der sozialen Integration zu entlasten, könne die Bereitschaft zum kommunikativen Handeln für seine Setzung eben nicht zur Bedingung gemacht werden.

Schließlich sei der in der Diskurstheorie des Rechts getroffene Verzicht auf das Einstimmigkeitserfordernis im Gesetzgebungsverfahren im Ergebnis nicht mit dem Demokratieprinzip in Form des Konsensprinzips zu vereinbaren.

Literatur
 Jürgen Habermas: Faktizität und Geltung. Beiträge zur Diskurstheorie des Rechts und des demokratischen Rechtsstaats. Suhrkamp Verlag, Frankfurt am Main, 1992. ISBN 978-3-518-58126-1.
 Robert Alexy: Theorie der juristischen Argumentation. 3. Aufl. (inklusive einer Erwiderung auf Kritiker), Suhrkamp Verlag, Frankfurt am Main, 1996.
 Martin Gelter, Kristoffel Grechenig: Juristischer Diskurs und Rechtsökonomie. In: Journal für Rechtspolitik (JRP) 2007, 30–41.
 Axel Tschentscher: Prozedurale Theorien der Gerechtigkeit. Nomos Verlag, Baden-Baden, 2000. ISBN 3-7890-6490-4.
 Jens Peter Brune: Moral und Recht. Zur Diskurstheorie des Rechts und der Demokratie von Jürgen Habermas. Verlag Karl Alber, 2011. ISBN 978-3-495-48430-2.
 Thomas McCarthy: Kritik der Verständigungsverhältnisse. Zur Theorie von Jürgen Habermas. Frankfurt a. M., 1989.
 Urs Marti: Diskursethische Legitimation und soziale Funktion des Rechts. Überlegungen zu J. Habermas' Diskurstheorie des Rechts und der Demokratie. in: Philippe Mastronardi (Hrsg.): Das Recht im Spannungsfeld utilitaristischer und deontologischer Ethik. Vorträge der Tagung der Schweizer Sektion der Internationalen Vereinigung für Rechts- und Sozialphilosophie (SVRSP) vom 15. und 16. November 2002 in Luzern, 1. Aufl. 2004. ISBN 978-3-515-08366-9.

Weblinks
 Diskurstheorie und Völkerrecht: Ein Interview mit Jürgen Habermas ZaöRV 2013, S. 295–303.
 Werner Zips, Matthäus Rest: Die Diskurstheorie von Jürgen Habermas Fakultät für Sozialwissenschaften, Universität Wien, abgerufen am 28. September 2017.
 Peter Ullrich: Diskursanalyse, Diskursforschung, Diskurstheorie : Ein- und Überblick In: Ulrike Freikamp u. a. (Hrsg.): Kritik mit Methode?: Forschungsmethoden und Gesellschaftskritik. Karl Dietz Verlag Berlin, 2008. ISBN 978-3-320-02136-8. S. 19–31.

Einzelnachweise

Jürgen Habermas
Rechtstheorie
Recht

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Well chickadees, I've been keeping a pretty low profile while fervently working on the business plan for the next stage of PersonalChefApproach.com. There is no shortage of enthusiasm when it comes to dreaming up new ways of helping YOU get dinner on the table every night. Whether it's whipping up a new recipe, building custom tools to streamline your shopping and cooking time on the website, or hanging out in the forum making sure new cooks feel comfortable in their kitchens (watch this space for all the new surprises I have in store for you).
This old dog has even enjoyed learning new tricks when it comes to food photography, video editing, and tackling social media, but the actual sitting still long enough to put it all on paper is NOT my strong suit.
So what's a girl to do? Fly home to enlist dad's help, of course! We spent the better part of last week locked away together in his office while he taught me the ins and outs of writing a business plan.
Not even my businessman father relishes the task – it is an arduous process, so I did appreciate every second of both his help, and the time together. It reminded me of all the loving hours he spent running up and down the streets of our neighborhood holding my bicycle until I could learn to balance for myself, and letting me behind the wheel of his car as he taught me how to drive (a nerve-wrecking task I've recently had the pleasure of being on the other side of ).
In fact, it was dad that braved all my Easy Bake oven and kitchen concoctions that eventually led to me becoming the personal chef I am today – although I have to attribute my creative side to my artist mother – who I also must thank for being patient while dad and I worked together on this endeavor.
Thank you dad, I guess I'll never be too old for a few flying lessons! I think I owe you a few turkey burgers for teaching me how to fly in the world of business – and for the recipe testing throughout the years!
PS. "Like" me on Facebook, and click the Free Sample App to try the Personal Chef Approach™, or subscribe to our newsletter for more about the PCA.
PPS. Tell me, what's the biggest obstacle you face in getting delicious homemade meals on the table?
This is one of the first recipes I ever wrote, and it won "best poultry burger in America" on Food Network's Ultimate Recipe Showdown, and happens to be my father's favorite. Since it is a little labor intensive, I would recommend doing double portions of at least the turkey burgers to freeze for a later date – why make a mess twice when you can do it all at once? After all it is about affording YOU the luxury of time!
(1) In my family, Daddy is still the most powerful word there is.
(2) Good for you for using his experience to help you – all those years in business make your father a great resource. And since you pay him in turkey burgers, a pretty economical one too.
(3) My biggest obstacle – being overscheduled. This "Supermom" thing (parent, spouse, chauffeur, daughter, employee, etc.) thing is exhausting! One reason that PCA is so great — when I can set aside a block of time on one day, it saves me on at least 8 other days.
Back to squeezing 36 hours of activity into a 24 hour day!