Medicinal plants - Wikipedia
Medicinal plants, also called medicinal herbs, have been discovered and used in traditional medicine practices since prehistoric times.
cytochrome P450
Plant extracts may interact with conventional drugs, both because they may provide an increased dose of similar compounds, and because some phytochemicals interfere with the body's systems that metabolise drugs in the liver including the <anchor>cytochrome P450</anchor> system, making the drugs last longer in the body and have a cumulative effect.[122] Plant medicines can be dangerous during pregnancy.[123] Since plants may contain many different substances, plant extracts may have complex effects on the human body.[5]
Cytochrome P450 - Wikipedia
Cytochrome P450 - Wikipedia[Jump to content](#bodyContent)

Main menu

Main menu

move to sidebarhide

Navigation


- [Main page](/wiki/Main_Page "Visit the main page [z]")
- [Contents](/wiki/Wikipedia:Contents "Guides to browsing Wikipedia")
- [Current events](/wiki/Portal:Current_events "Articles related to current events")
- [Random article](/wiki/Special:Random "Visit a randomly selected article [x]")
- [About Wikipedia](/wiki/Wikipedia:About "Learn about Wikipedia and how it works")
- [Contact us](//en.wikipedia.org/wiki/Wikipedia:Contact_us "How to contact Wikipedia")
- [Donate](https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en "Support us by donating to the Wikimedia Foundation")

Contribute


- [Help](/wiki/Help:Contents "Guidance on how to use and edit Wikipedia")
- [Learn to edit](/wiki/Help:Introduction "Learn how to edit Wikipedia")
- [Community portal](/wiki/Wikipedia:Community_portal "The hub for editors")
- [Recent changes](/wiki/Special:RecentChanges "A list of recent changes to Wikipedia [r]")
- [Upload file](/wiki/Wikipedia:File_upload_wizard "Add images or other media for use on Wikipedia")

[![](/static/images/icons/wikipedia.png)![Wikipedia](/static/images/mobile/copyright/wikipedia-wordmark-en.svg)![The Free Encyclopedia](/static/images/mobile/copyright/wikipedia-tagline-en.svg)](/wiki/Main_Page)

[Search](/wiki/Special:Search "Search Wikipedia [f]")

Search

Appearance

- [Create account](/w/index.php?title=Special:CreateAccount&returnto=Cytochrome+P450 "You are encouraged to create an account and log in; however, it is not mandatory")
- [Log in](/w/index.php?title=Special:UserLogin&returnto=Cytochrome+P450 "You're encouraged to log in; however, it's not mandatory. [o]")

Personal tools

- [Create account](/w/index.php?title=Special:CreateAccount&returnto=Cytochrome+P450 "You are encouraged to create an account and log in; however, it is not mandatory")
- [Log in](/w/index.php?title=Special:UserLogin&returnto=Cytochrome+P450 "You're encouraged to log in; however, it's not mandatory. [o]")

Pages for logged out editors [learn more](/wiki/Help:Introduction)

- [Contributions](/wiki/Special:MyContributions "A list of edits made from this IP address [y]")
- [Talk](/wiki/Special:MyTalk "Discussion about edits from this IP address [n]")

## Contents

move to sidebarhide

- (Top)

- [1Nomenclature](#Nomenclature)
- [2Classification](#Classification)
- [3Related hydroxylation enzymes](#Related_hydroxylation_enzymes)
- [4Mechanism](#Mechanism)Toggle Mechanism subsection  - [4.1Structure](#Structure)
  - [4.2Catalytic cycle](#Catalytic_cycle)
  - [4.3Spectroscopy](#Spectroscopy)
- [5See also](#See_also)
- [6Further reading](#Further_reading)
- [7References](#References)

Toggle the table of contents

# Cytochrome P450

34 languages

- [Afrikaans](https://af.wikipedia.org/wiki/Sitochroom_P450 "Sitochroom P450 – Afrikaans")
- [العربية](https://ar.wikipedia.org/wiki/%D8%B3%D9%8A%D8%AA%D9%88%D9%83%D8%B1%D9%88%D9%85_%D8%A8%D9%8A450 "سيتوكروم بي450 – Arabic")
- [Bosanski](https://bs.wikipedia.org/wiki/Citohrom_P450 "Citohrom P450 – Bosnian")
- [Català](https://ca.wikipedia.org/wiki/Citocrom_p450 "Citocrom p450 – Catalan")
- [Čeština](https://cs.wikipedia.org/wiki/Cytochrom_P450 "Cytochrom P450 – Czech")
- [Deutsch](https://de.wikipedia.org/wiki/Cytochrom_P450 "Cytochrom P450 – German")
- [Eesti](https://et.wikipedia.org/wiki/Ts%C3%BCtokroom_P450 "Tsütokroom P450 – Estonian")
- [Ελληνικά](https://el.wikipedia.org/wiki/%CE%9A%CF%85%CF%84%CF%8C%CF%87%CF%81%CF%89%CE%BC%CE%B1_P450 "Κυτόχρωμα P450 – Greek")
- [Español](https://es.wikipedia.org/wiki/Citocromo_P450 "Citocromo P450 – Spanish")
- [Esperanto](https://eo.wikipedia.org/wiki/Citokromo_p450 "Citokromo p450 – Esperanto")
- [فارسی](https://fa.wikipedia.org/wiki/%D8%B3%DB%8C%D8%AA%D9%88%DA%A9%D8%B1%D9%88%D9%85_%D9%BE%DB%8C_%DB%B4%DB%B5%DB%B0 "سیتوکروم پی ۴۵۰ – Persian")
- [Français](https://fr.wikipedia.org/wiki/Cytochrome_P450 "Cytochrome P450 – French")
- [Galego](https://gl.wikipedia.org/wiki/Citocromo_P450 "Citocromo P450 – Galician")
- [한국어](https://ko.wikipedia.org/wiki/%EC%82%AC%EC%9D%B4%ED%86%A0%ED%81%AC%EB%A1%AC_P450 "사이토크롬 P450 – Korean")
- [Hrvatski](https://hr.wikipedia.org/wiki/Citokrom_P-450 "Citokrom P-450 – Croatian")
- [Bahasa Indonesia](https://id.wikipedia.org/wiki/Sitokrom_P450 "Sitokrom P450 – Indonesian")
- [Italiano](https://it.wikipedia.org/wiki/Citocromo_P450 "Citocromo P450 – Italian")
- [Latina](https://la.wikipedia.org/wiki/Cytochroma_P450 "Cytochroma P450 – Latin")
- [Magyar](https://hu.wikipedia.org/wiki/Citokr%C3%B3m_P450 "Citokróm P450 – Hungarian")
- [Nederlands](https://nl.wikipedia.org/wiki/Cytochroom_P450 "Cytochroom P450 – Dutch")
- [日本語](https://ja.wikipedia.org/wiki/%E3%82%B7%E3%83%88%E3%82%AF%E3%83%AD%E3%83%A0P450 "シトクロムP450 – Japanese")
- [Norsk bokmål](https://no.wikipedia.org/wiki/Cytokrom_P450 "Cytokrom P450 – Norwegian Bokmål")
- [Polski](https://pl.wikipedia.org/wiki/Cytochrom_P450 "Cytochrom P450 – Polish")
- [Português](https://pt.wikipedia.org/wiki/Citocromo_P450 "Citocromo P450 – Portuguese")
- [Română](https://ro.wikipedia.org/wiki/Citocrom_P450 "Citocrom P450 – Romanian")
- [Русский](https://ru.wikipedia.org/wiki/%D0%A6%D0%B8%D1%82%D0%BE%D1%85%D1%80%D0%BE%D0%BC_P450 "Цитохром P450 – Russian")
- [Slovenščina](https://sl.wikipedia.org/wiki/Citokrom_P450 "Citokrom P450 – Slovenian")
- [Српски / srpski](https://sr.wikipedia.org/wiki/Citohrom_P450 "Citohrom P450 – Serbian")
- [Srpskohrvatski / српскохрватски](https://sh.wikipedia.org/wiki/Citohrom_P450 "Citohrom P450 – Serbo-Croatian")
- [Suomi](https://fi.wikipedia.org/wiki/Sytokromi_P450 "Sytokromi P450 – Finnish")
- [Svenska](https://sv.wikipedia.org/wiki/Cytokrom_P450 "Cytokrom P450 – Swedish")
- [Türkçe](https://tr.wikipedia.org/wiki/Sitokrom_P450 "Sitokrom P450 – Turkish")
- [Українська](https://uk.wikipedia.org/wiki/%D0%A6%D0%B8%D1%82%D0%BE%D1%85%D1%80%D0%BE%D0%BC_%D0%A0-450 "Цитохром Р-450 – Ukrainian")
- [中文](https://zh.wikipedia.org/wiki/%E7%BB%86%E8%83%9E%E8%89%B2%E7%B4%A0P450 "细胞色素P450 – Chinese")

[Edit links](https://www.wikidata.org/wiki/Special:EntityPage/Q407693#sitelinks-wikipedia "Edit interlanguage links")

- [Article](/wiki/Cytochrome_P450 "View the content page [c]")
- [Talk](/wiki/Talk:Cytochrome_P450 "Discuss improvements to the content page [t]")

English

- [Read](/wiki/Cytochrome_P450)
- [Edit](/w/index.php?title=Cytochrome_P450&action=edit "Edit this page [e]")
- [View history](/w/index.php?title=Cytochrome_P450&action=history "Past revisions of this page [h]")

Tools

Tools

move to sidebarhide

Actions


- [Read](/wiki/Cytochrome_P450)
- [Edit](/w/index.php?title=Cytochrome_P450&action=edit "Edit this page [e]")
- [View history](/w/index.php?title=Cytochrome_P450&action=history)

General


- [What links here](/wiki/Special:WhatLinksHere/Cytochrome_P450 "List of all English Wikipedia pages containing links to this page [j]")
- [Related changes](/wiki/Special:RecentChangesLinked/Cytochrome_P450 "Recent changes in pages linked from this page [k]")
- [Upload file](/wiki/Wikipedia:File_Upload_Wizard "Upload files [u]")
- [Special pages](/wiki/Special:SpecialPages "A list of all special pages [q]")
- [Permanent link](/w/index.php?title=Cytochrome_P450&oldid=1243845622 "Permanent link to this revision of this page")
- [Page information](/w/index.php?title=Cytochrome_P450&action=info "More information about this page")
- [Cite this page](/w/index.php?title=Special:CiteThisPage&page=Cytochrome_P450&id=1243845622&wpFormIdentifier=titleform "Information on how to cite this page")
- [Get shortened URL](/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FCytochrome_P450)
- [Download QR code](/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FCytochrome_P450)
- [Wikidata item](https://www.wikidata.org/wiki/Special:EntityPage/Q407693 "Structured data on this page hosted by Wikidata [g]")

Print/export


- [Download as PDF](/w/index.php?title=Special:DownloadAsPdf&page=Cytochrome_P450&action=show-download-screen "Download this page as a PDF file")
- [Printable version](/w/index.php?title=Cytochrome_P450&printable=yes "Printable version of this page [p]")

In other projects


- [Wikimedia Commons](https://commons.wikimedia.org/wiki/Category:Cytochrome_P450)

Appearance

move to sidebarhide

From Wikipedia, the free encyclopedia

Class of enzymes

Further information: [Cytochrome P450 (individual enzymes)](/wiki/Cytochrome_P450_(individual_enzymes) "Cytochrome P450 (individual enzymes)")

Cytochrome P450[![](//upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Structure_of_lanosterol_14_%CE%B1-demethylase_%28CYP51%29.png/220px-Structure_of_lanosterol_14_%CE%B1-demethylase_%28CYP51%29.png)](/wiki/File:Structure_of_lanosterol_14_%CE%B1-demethylase_(CYP51).png)

Structure of lanosterol 14α-demethylase ( [CYP51](/wiki/CYP51 "CYP51"))

IdentifiersSymbolp450[Pfam](/wiki/Pfam "Pfam")[PF00067](https://www.ebi.ac.uk/interpro/entry/pfam/PF00067)[InterPro](/wiki/InterPro "InterPro")[IPR001128](https://www.ebi.ac.uk/interpro/entry/IPR001128)[PROSITE](/wiki/PROSITE "PROSITE")[PDOC00081](https://prosite.expasy.org/PDOC00081)[SCOP2](/wiki/Structural_Classification_of_Proteins "Structural Classification of Proteins")[2cpp](http://scop2.mrc-lmb.cam.ac.uk/search?t=txt;q=2cpp) / [SCOPe](https://scop.berkeley.edu/pdb/code=2cpp) / [SUPFAM](http://supfam.org/SUPERFAMILY/cgi-bin/search.cgi?search_field=2cpp)[OPM superfamily](/wiki/Orientations_of_Proteins_in_Membranes_database "Orientations of Proteins in Membranes database")[39](https://opm.phar.umich.edu/protein_superfamilies/39)[OPM protein](/wiki/Orientations_of_Proteins_in_Membranes_database "Orientations of Proteins in Membranes database")[2bdm](https://opm.phar.umich.edu/proteins?search=2bdm)[CDD](/wiki/Conserved_Domain_Database "Conserved Domain Database")[cd00302](https://www.ncbi.nlm.nih.gov/Structure/cdd/cddsrv.cgi?uid=cd00302)[Membranome](/wiki/Membranome_database "Membranome database")[265](http://membranome.org/protein_superfamilies/265)Available protein structures:[Pfam](/wiki/Pfam "Pfam")[structures](http://pfam.xfam.org/family/PF00067?tab=pdbBlock) / [ECOD](http://prodata.swmed.edu/ecod/complete/search?kw=PF00067)[PDB](/wiki/Protein_Data_Bank "Protein Data Bank")[RCSB PDB](https://www.rcsb.org/search?q=rcsb_polymer_entity_annotation.annotation_id:PF00067%20AND%20rcsb_polymer_entity_annotation.type:Pfam); [PDBe](https://www.ebi.ac.uk/pdbe/entry/search/index?pfam_accession:PF00067); [PDBj](https://pdbj.org/search/pdb?other_db_select=PFam&other_db_field=PF00067)[PDBsum](/wiki/PDBsum "PDBsum")[structure summary](https://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/pdbsum/GetPfamStr.pl?pfam_id=PF00067)

**Cytochromes P450** ( **P450s** or **CYPs**) are a [superfamily](/wiki/Protein_superfamily "Protein superfamily") of [enzymes](/wiki/Enzyme "Enzyme") containing [heme](/wiki/Heme "Heme") as a [cofactor](/wiki/Cofactor_(biochemistry) "Cofactor (biochemistry)") that mostly, but not exclusively, function as [monooxygenases](/wiki/Monooxygenase "Monooxygenase").[\[1\]](#cite_note-:0-1) However, they are not omnipresent; for example, they have not been found in _[Escherichia coli](/wiki/Escherichia_coli "Escherichia coli")_.[\[2\]](#cite_note-pmid12369887-2) In mammals, these enzymes oxidize [steroids](/wiki/Steroid "Steroid"), [fatty acids](/wiki/Fatty_acid "Fatty acid"), [xenobiotics](/wiki/Xenobiotic "Xenobiotic"), and participate in many biosyntheses.[\[1\]](#cite_note-:0-1) By hydroxylation, CYP450 enzymes convert xenobiotics into hydrophilic derivatives, which are more readily excreted.

P450s are, in general, the terminal oxidase enzymes in [electron transfer](/wiki/Electron_transfer "Electron transfer") chains, broadly categorized as [P450-containing systems](/wiki/P450-containing_systems "P450-containing systems"). The term "P450" is derived from the [spectrophotometric](/wiki/Spectrophotometry "Spectrophotometry") peak at the [wavelength](/wiki/Wavelength "Wavelength") of the [absorption maximum](/wiki/Absorption_spectroscopy "Absorption spectroscopy") of the enzyme (450 [nm](/wiki/Nanometre "Nanometre")) when it is in the [reduced](/wiki/Redox "Redox") state and complexed with [carbon monoxide](/wiki/Carbon_monoxide "Carbon monoxide"). Most P450s require a protein partner to deliver one or more [electrons](/wiki/Electron "Electron") to reduce the [iron](/wiki/Iron "Iron") (and eventually molecular [oxygen](/wiki/Oxygen "Oxygen")).

## Nomenclature

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=1 "Edit section: Nomenclature")\]

[Genes](/wiki/Gene "Gene") encoding P450 enzymes, and the enzymes themselves, are designated with the [root symbol](/wiki/Gene_nomenclature#Symbol_and_name "Gene nomenclature") **CYP** for the [superfamily](/wiki/Protein_superfamily "Protein superfamily"), followed by a number indicating the [gene family](/wiki/Gene_family "Gene family"), a capital letter indicating the subfamily, and another numeral for the individual gene. The convention is to _[italicize](/wiki/Italic_type "Italic type")_ the name when referring to the gene. For example, _CYP2E1_ is the gene that encodes the enzyme [CYP2E1](/wiki/CYP2E1 "CYP2E1")—one of the enzymes involved in [paracetamol](/wiki/Paracetamol "Paracetamol") (acetaminophen) metabolism. The **CYP** nomenclature is the official naming convention, although occasionally **CYP450** or **CYP450** is used synonymously. These names should never be used as according to the nomenclature convention (as they denote a P450 in family number 450). However, some gene or enzyme names for P450s are also referred to by historical names (e.g. P450BM3 for CYP102A1) or functional names, denoting the catalytic activity and the name of the compound used as substrate. Examples include [CYP5A1](/wiki/CYP5A1 "CYP5A1"), [thromboxane](/wiki/Thromboxane "Thromboxane") A2 synthase, abbreviated to [TBXAS1](/wiki/Thromboxane-A_synthase "Thromboxane-A synthase") ( **T** hrom **B** o **X** ane **A** 2 **S** ynthase **1**), and [CYP51A1](/wiki/CYP51A1 "CYP51A1"), lanosterol 14-α-demethylase, sometimes unofficially abbreviated to LDM according to its substrate ( **L** anosterol) and activity ( **D** e **M** ethylation).[\[3\]](#cite_note-3)

The current nomenclature guidelines suggest that members of new CYP families share at least 40% [amino-acid](/wiki/Amino_acid "Amino acid") identity, while members of subfamilies must share at least 55% amino-acid identity. Nomenclature committees assign and track both base gene names ( [Cytochrome P450 Homepage](http://drnelson.uthsc.edu/CytochromeP450.html) [Archived](https://web.archive.org/web/20100627184446/http://drnelson.uthsc.edu/CytochromeP450.html) 2010-06-27 at the [Wayback Machine](/wiki/Wayback_Machine "Wayback Machine")) and [allele](/wiki/Allele "Allele") names ( [CYP Allele Nomenclature Committee](https://www.pharmvar.org//)).[\[4\]](#cite_note-4)[\[5\]](#cite_note-5)

## Classification

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=2 "Edit section: Classification")\]

Main article: [P450-containing systems](/wiki/P450-containing_systems "P450-containing systems")

Based on the nature of the electron transfer proteins, P450s can be classified into several groups:[\[6\]](#cite_note-1996-Hanukoglu-6)

Microsomal P450 systemsin which electrons are transferred from [NADPH](/wiki/Nicotinamide_adenine_dinucleotide_phosphate "Nicotinamide adenine dinucleotide phosphate") via [cytochrome P450 reductase](/wiki/Cytochrome_P450_reductase "Cytochrome P450 reductase") (variously CPR, POR, or CYPOR). [Cytochrome b5](/wiki/Cytochrome_b5 "Cytochrome b5") (cyb5) can also contribute reducing power to this system after being reduced by [cytochrome b5 reductase](/wiki/Cytochrome_b5_reductase "Cytochrome b5 reductase") (CYB5R).Mitochondrial P450 systemswhich employ [adrenodoxin reductase](/wiki/Adrenodoxin_reductase "Adrenodoxin reductase") and [adrenodoxin](/wiki/Adrenodoxin "Adrenodoxin") to transfer electrons from NADPH to P450.Bacterial P450 systemswhich employ a [ferredoxin reductase](/wiki/Ferredoxin_reductase "Ferredoxin reductase") and a [ferredoxin](/wiki/Ferredoxin "Ferredoxin") to transfer electrons to P450.CYB5R/cyb5/P450 systemsin which both electrons required by the CYP come from cytochrome b5.FMN/Fd/P450 systemsoriginally found in _[Rhodococcus](/wiki/Rhodococcus "Rhodococcus")_ species, in which a [FMN](/wiki/Flavin_mononucleotide "Flavin mononucleotide")-domain-containing [reductase](/wiki/Reductase "Reductase") is fused to the CYP.P450 only systemswhich do not require external reducing power. Notable ones include [thromboxane synthase](/wiki/Thromboxane_synthase "Thromboxane synthase") (CYP5), [prostacyclin synthase](/wiki/Prostacyclin_synthase "Prostacyclin synthase") (CYP8), and CYP74A ( [allene oxide synthase](/w/index.php?title=Allene_oxide_synthase&action=edit&redlink=1 "Allene oxide synthase (page does not exist)")).

The most common reaction catalyzed by cytochromes P450 is a monooxygenase reaction, e.g., insertion of one atom of oxygen into the aliphatic position of an organic substrate (RH), while the other oxygen atom is [reduced](/wiki/Redox "Redox") to water:

RH + O2 \+ NADPH + H+ → ROH + H2O + NADP+

## Related hydroxylation enzymes

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=3 "Edit section: Related hydroxylation enzymes")\]

Many [hydroxylation](/wiki/Hydroxylation "Hydroxylation") reactions (insertion of [hydroxyl](/wiki/Hydroxyl "Hydroxyl") groups) use CYP enzymes, but many other hydroxylases exist. [Alpha-ketoglutarate-dependent hydroxylases](/wiki/Alpha-ketoglutarate-dependent_hydroxylases "Alpha-ketoglutarate-dependent hydroxylases") also rely on an Fe=O intermediate but lack hemes. Methane monooxygenase, which converts methane to methanol, are non-heme iron-and iron-copper-based enzymes.[\[7\]](#cite_note-7)

## Mechanism

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=4 "Edit section: Mechanism")\]

[![The P450 catalytic cycle](//upload.wikimedia.org/wikipedia/commons/thumb/3/39/P450cycle.svg/400px-P450cycle.svg.png)](/wiki/File:P450cycle.svg) The "Fe(V) intermediate" at the bottom left is a simplification: it is an Fe(IV) with a [radical heme ligand](/wiki/Noninnocent_ligand "Noninnocent ligand").

### Structure

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=5 "Edit section: Structure")\]

The active site of cytochrome P450 contains a heme-iron center. The iron is tethered to the protein via a [cysteine](/wiki/Cysteine "Cysteine") [thiolate](/wiki/Thiolate "Thiolate") [ligand](/wiki/Ligand "Ligand"). This cysteine and several flanking residues are highly conserved in known P450s, and have the formal [PROSITE](/wiki/PROSITE "PROSITE") signature consensus pattern \[FW\] - \[SGNH\] - x - \[GD\] - {F} - \[RKHPT\] - {P} - C \- \[LIVMFAP\] - \[GAD\].[\[8\]](#cite_note-8) In general, the P450 catalytic cycle proceeds as follows:

### Catalytic cycle

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=6 "Edit section: Catalytic cycle")\]

1. Substrate binds in proximity to the [heme group](/wiki/Heme_group "Heme group"), on the side opposite to the axial thiolate. Substrate binding induces a change in the conformation of the active site, often displacing a water molecule from the distal axial coordination position of the heme iron,[\[9\]](#cite_note-P450Mechanism-9) and changing the state of the heme iron from low-spin to high-spin.[\[10\]](#cite_note-HiResCam-10)
2. Substrate binding induces electron transfer from NAD(P)H via [cytochrome P450 reductase](/wiki/Cytochrome_P450_reductase "Cytochrome P450 reductase") or another associated [reductase](/wiki/Reductase "Reductase"),[\[11\]](#cite_note-P450pot-11) converting Fe(III) to Fe(II).
3. Molecular oxygen binds to the resulting ferrous heme center at the distal axial coordination position, initially giving a [dioxygen adduct](/wiki/Transition_metal_dioxygen_complex "Transition metal dioxygen complex") similar to oxy-myoglobin.
4. A second electron is transferred, from either [cytochrome P450 reductase](/wiki/Cytochrome_P450_reductase "Cytochrome P450 reductase"), [ferredoxins](/wiki/Ferredoxin "Ferredoxin"), or [cytochrome b5](/wiki/Cytochrome_b5 "Cytochrome b5"), reducing the Fe-O2 adduct to give a short-lived peroxo state.
5. The peroxo group formed in step 4 is rapidly protonated twice, releasing one molecule of water and forming the highly reactive species referred to as **P450 Compound 1** (or just Compound I). This highly reactive intermediate was isolated in 2010,[\[12\]](#cite_note-P450-I-12) P450 Compound 1 is an iron(IV) oxo (or [ferryl](/wiki/Ferryl "Ferryl")) species with an additional oxidizing equivalent [delocalized](/wiki/Delocalized "Delocalized") over the [porphyrin](/wiki/Porphyrin "Porphyrin") and thiolate ligands. Evidence for the alternative perferryl [iron(V)-oxo](/wiki/High-valent_iron "High-valent iron")[\[9\]](#cite_note-P450Mechanism-9) is lacking.[\[12\]](#cite_note-P450-I-12)
6. Depending on the substrate and enzyme involved, P450 enzymes can catalyze any of a wide variety of reactions. A hypothetical hydroxylation is illustrated. After the hydroxylated product has been released from the active site, the enzyme returns to its original state, with a water molecule returning to occupy the distal coordination position of the iron nucleus.

[![](//upload.wikimedia.org/wikipedia/commons/thumb/9/91/FeIVO_2.tif/lossy-page1-300px-FeIVO_2.tif.jpg)](/wiki/File:FeIVO_2.tif) [Oxygen rebound mechanism](/wiki/Oxygen_rebound_mechanism "Oxygen rebound mechanism") utilized by cytochrome P450 for conversion of hydrocarbons to alcohols via the action of "compound I", an iron(IV) oxide bound to a heme radical cation.

1. An alternative route for mono-oxygenation is via the "peroxide shunt" (path "S" in figure). This pathway entails oxidation of the ferric-substrate complex with oxygen-atom donors such as peroxides and hypochlorites.[\[13\]](#cite_note-p450struc-13) A hypothetical peroxide "XOOH" is shown in the diagram.

Mechanistic details, including the [oxygen rebound mechanism](/wiki/Oxygen_rebound_mechanism "Oxygen rebound mechanism"), have been investigated with synthetic analogues, consisting of iron oxo heme complexes.[\[14\]](#cite_note-14)

### Spectroscopy

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=7 "Edit section: Spectroscopy")\]

Binding of substrate is reflected in the spectral properties of the enzyme, with an increase in absorbance at 390 nm and a decrease at 420 nm. This can be measured by difference spectroscopies and is referred to as the "type I" difference spectrum (see inset graph in figure). Some substrates cause an opposite change in spectral properties, a "reverse type I" spectrum, by processes that are as yet unclear. Inhibitors and certain substrates that bind directly to the heme iron give rise to the type II difference spectrum, with a maximum at 430 nm and a minimum at 390 nm (see inset graph in figure). If no reducing equivalents are available, this complex may remain stable, allowing the degree of binding to be determined from absorbance measurements _in vitro_[\[13\]](#cite_note-p450struc-13)
C: If carbon monoxide (CO) binds to reduced P450, the catalytic cycle is interrupted. This reaction yields the classic CO difference spectrum with a maximum at 450 nm. However, the interruptive and inhibitory effects of CO varies upon different CYPs such that the CYP3A family is relatively less affected.[\[15\]](#cite_note-15)[\[16\]](#cite_note-16)

## See also

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=8 "Edit section: See also")\]

- [![icon](//upload.wikimedia.org/wikipedia/commons/thumb/2/2d/Issoria_lathonia.jpg/32px-Issoria_lathonia.jpg)](/wiki/File:Issoria_lathonia.jpg)[Biology portal](/wiki/Portal:Biology "Portal:Biology")

- [Cytochrome P450 oxidoreductase deficiency](/wiki/Cytochrome_P450_oxidoreductase_deficiency "Cytochrome P450 oxidoreductase deficiency")
- [Cytochrome P450 engineering](/wiki/Cytochrome_P450_engineering "Cytochrome P450 engineering")

## Further reading

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=9 "Edit section: Further reading")\]

- Estabrook RW (December 2003). "A passion for P450s (Remembrances of the early history of research on cytochrome P450)". _Drug Metabolism and Disposition_. **31** (12): 1461–1473. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1124/dmd.31.12.1461](https://doi.org/10.1124%2Fdmd.31.12.1461). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [14625342](https://pubmed.ncbi.nlm.nih.gov/14625342). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [43655270](https://api.semanticscholar.org/CorpusID:43655270).

## References

\[ [edit](/w/index.php?title=Cytochrome_P450&action=edit&section=10 "Edit section: References")\]

01. ^ [_**a**_](#cite_ref-:0_1-0) [_**b**_](#cite_ref-:0_1-1)["Cytochrome P450"](http://www.ebi.ac.uk/interpro/entry/IPR001128). _InterPro_.
02. **[^](#cite_ref-pmid12369887_2-0)**Danielson PB (December 2002). "The cytochrome P450 superfamily: biochemistry, evolution and drug metabolism in humans". _Current Drug Metabolism_. **3** (6): 561–597. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.2174/1389200023337054](https://doi.org/10.2174%2F1389200023337054). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [12369887](https://pubmed.ncbi.nlm.nih.gov/12369887).
03. **[^](#cite_ref-3)**["NCBI sequence viewer"](https://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?db=protein&id=3915660). Retrieved 2007-11-19.
04. **[^](#cite_ref-4)**Nelson DR (October 2009). ["The cytochrome p450 homepage"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3500189). _Human Genomics_. **4** (1): 59–65. [doi](/wiki/Doi_(identifier) "Doi (identifier)"):[10.1186/1479-7364-4-1-59](https://doi.org/10.1186%2F1479-7364-4-1-59). [PMC](/wiki/PMC_(identifier) "PMC (identifier)") [3500189](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3500189). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [19951895](https://pubmed.ncbi.nlm.nih.gov/19951895).
05. **[^](#cite_ref-5)**Nelson DR (January 2011). "Progress in tracing the evolutionary paths of cytochrome P450". _Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics_. **1814** (1): 14–18. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1016/j.bbapap.2010.08.008](https://doi.org/10.1016%2Fj.bbapap.2010.08.008). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [20736090](https://pubmed.ncbi.nlm.nih.gov/20736090).
06. **[^](#cite_ref-1996-Hanukoglu_6-0)**Hanukoglu I (1996). ["Electron transfer proteins of cytochrome P450 systems"](https://www.science.co.il/hi/pub/Electron-transfer-proteins-of-cytochrome-P450-systems.pdf)(PDF). _Adv. Mol. Cell Biol_. Advances in Molecular and Cell Biology. **14**: 29–55. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1016/S1569-2558(08)60339-2](https://doi.org/10.1016%2FS1569-2558%2808%2960339-2). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-0-7623-0113-3](/wiki/Special:BookSources/978-0-7623-0113-3 "Special:BookSources/978-0-7623-0113-3").
07. **[^](#cite_ref-7)**Tucci FJ, Rosenzweig AC (February 2024). ["Direct Methane Oxidation by Copper- and Iron-Dependent Methane Monooxygenases"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10923174). _Chemical Reviews_. **124** (3): 1288–1320. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1021/acs.chemrev.3c00727](https://doi.org/10.1021%2Facs.chemrev.3c00727). [PMC](/wiki/PMC_(identifier) "PMC (identifier)") [10923174](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10923174). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [38305159](https://pubmed.ncbi.nlm.nih.gov/38305159).
08. **[^](#cite_ref-8)**[\[1\]](http://www.expasy.org/cgi-bin/nicedoc.pl?PDOC00081) [Archived](https://web.archive.org/web/20191018181235/https://web.expasy.org/cgi-bin/unavailable.cgi?type=redirect&query=nicedoc.pl) 2019-10-18 at the [Wayback Machine](/wiki/Wayback_Machine "Wayback Machine") [PROSITE](/wiki/PROSITE "PROSITE") consensus pattern for P450
09. ^ [_**a**_](#cite_ref-P450Mechanism_9-0) [_**b**_](#cite_ref-P450Mechanism_9-1)Meunier B, de Visser SP, Shaik S (September 2004). "Mechanism of oxidation reactions catalyzed by cytochrome p450 enzymes". _Chemical Reviews_. **104** (9): 3947–3980. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1021/cr020443g](https://doi.org/10.1021%2Fcr020443g). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [15352783](https://pubmed.ncbi.nlm.nih.gov/15352783). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [33927145](https://api.semanticscholar.org/CorpusID:33927145).
10. **[^](#cite_ref-HiResCam_10-0)**Poulos TL, Finzel BC, Howard AJ (June 1987). "High-resolution crystal structure of cytochrome P450cam". _Journal of Molecular Biology_. **195** (3): 687–700. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1016/0022-2836(87)90190-2](https://doi.org/10.1016%2F0022-2836%2887%2990190-2). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [3656428](https://pubmed.ncbi.nlm.nih.gov/3656428).
11. **[^](#cite_ref-P450pot_11-0)**Sligar SG, Cinti DL, Gibson GG, Schenkman JB (October 1979). "Spin state control of the hepatic cytochrome P450 redox potential". _Biochemical and Biophysical Research Communications_. **90** (3): 925–932. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1016/0006-291X(79)91916-8](https://doi.org/10.1016%2F0006-291X%2879%2991916-8). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [228675](https://pubmed.ncbi.nlm.nih.gov/228675).
12. ^ [_**a**_](#cite_ref-P450-I_12-0) [_**b**_](#cite_ref-P450-I_12-1)Rittle J, Green MT (November 2010). "Cytochrome P450 Compound I: Capture, Characterization, and C-H Bond Activation Kinetics". _Science_. **330** (6006): 933–937. [Bibcode](/wiki/Bibcode_(identifier) "Bibcode (identifier)"): [2010Sci...330..933R](https://ui.adsabs.harvard.edu/abs/2010Sci...330..933R). [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1126/science.1193478](https://doi.org/10.1126%2Fscience.1193478). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [21071661](https://pubmed.ncbi.nlm.nih.gov/21071661). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [206528205](https://api.semanticscholar.org/CorpusID:206528205).
13. ^ [_**a**_](#cite_ref-p450struc_13-0) [_**b**_](#cite_ref-p450struc_13-1)Ortiz de Montellano PR (2005). _Cytochrome P450: structure, mechanism, and biochemistry_ (3rd ed.). New York: Kluwer Academic/Plenum Publishers. [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-0-306-48324-0](/wiki/Special:BookSources/978-0-306-48324-0 "Special:BookSources/978-0-306-48324-0").
14. **[^](#cite_ref-14)**Huang X, Groves JT (March 2018). ["Oxygen Activation and Radical Transformations in Heme Proteins and Metalloporphyrins"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5855008). _Chemical Reviews_. **118** (5): 2491–2553. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1021/acs.chemrev.7b00373](https://doi.org/10.1021%2Facs.chemrev.7b00373). [PMC](/wiki/PMC_(identifier) "PMC (identifier)") [5855008](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5855008). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [29286645](https://pubmed.ncbi.nlm.nih.gov/29286645).
15. **[^](#cite_ref-15)**Hopper CP, Zambrana PN, Goebel U, Wollborn J (June 2021). "A brief history of carbon monoxide and its therapeutic origins". _Nitric Oxide_. 111–112: 45–63. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1016/j.niox.2021.04.001](https://doi.org/10.1016%2Fj.niox.2021.04.001). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [33838343](https://pubmed.ncbi.nlm.nih.gov/33838343). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [233205099](https://api.semanticscholar.org/CorpusID:233205099).
16. **[^](#cite_ref-16)**Smith AT, Pazicni S, Marvin KA, Stevens DJ, Paulsen KM, Burstyn JN (April 2015). "Functional divergence of heme-thiolate proteins: a classification based on spectroscopic attributes". _Chemical Reviews_. **115** (7): 2532–2558. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1021/cr500056m](https://doi.org/10.1021%2Fcr500056m). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [25763468](https://pubmed.ncbi.nlm.nih.gov/25763468).

- [v](/wiki/Template:Hemeproteins "Template:Hemeproteins")
- [t](/wiki/Template_talk:Hemeproteins "Template talk:Hemeproteins")
- [e](/wiki/Special:EditPage/Template:Hemeproteins "Special:EditPage/Template:Hemeproteins")

[Proteins](/wiki/Protein "Protein") that contain [heme](/wiki/Heme "Heme") ( [hemoproteins](/wiki/Hemoprotein "Hemoprotein"))

[Globins](/wiki/Globin "Globin")

[Hemoglobin](/wiki/Hemoglobin "Hemoglobin")

Subunits

_Alpha locus on [16](/wiki/Chromosome_16 "Chromosome 16"):_

- _α_
  - [HBA1](/wiki/Hemoglobin_subunit_alpha "Hemoglobin subunit alpha")
  - [HBA2](/wiki/Hemoglobin,_alpha_2 "Hemoglobin, alpha 2")
  - [pseudo](/wiki/HBAP1 "HBAP1")
- _ζ_
  - [HBZ](/wiki/Hemoglobin_subunit_zeta "Hemoglobin subunit zeta")
- _θ_
  - [HBQ1](/wiki/HBQ1 "HBQ1")
- _μ_
  - [HBM](/wiki/Mu_hemoglobin "Mu hemoglobin")

_[Beta locus](/wiki/Human_%CE%B2-globin_locus "Human β-globin locus") on [11](/wiki/Chromosome_11 "Chromosome 11"):_

- _β_
  - [HBB](/wiki/Hemoglobin_subunit_beta "Hemoglobin subunit beta")
- _δ_
  - [HBD](/wiki/HBD "HBD")
- _γ_
  - [HBG1](/wiki/HBG1 "HBG1")
  - [HBG2](/wiki/HBG2 "HBG2")
- _ε_
  - [HBE1](/wiki/HBE1 "HBE1")

[Tetramers](/wiki/Tetrameric_protein "Tetrameric protein")

_stages of_

_development:_

Embryonic

- [HbE Gower 1](/wiki/Embryonic_hemoglobin "Embryonic hemoglobin") (ζ2ε2)
- [HbE Gower 2](/wiki/Embryonic_hemoglobin "Embryonic hemoglobin") (α2ε2)
- [HbE Portland I](/wiki/Embryonic_hemoglobin "Embryonic hemoglobin") (ζ2γ2)
- [HbE Portland II](/wiki/Embryonic_hemoglobin "Embryonic hemoglobin") (ζ2β2)

Fetal

- [HbF/Fetal](/wiki/Fetal_hemoglobin "Fetal hemoglobin") (α2γ2)
- [HbA](/wiki/Hemoglobin_A "Hemoglobin A") (α2β2)

Adult

- [HbA](/wiki/Hemoglobin_A "Hemoglobin A") (α2β2)
- [HbA2](/wiki/Hemoglobin_A2 "Hemoglobin A2") (α2δ2)
- [HbF/Fetal](/wiki/Fetal_hemoglobin "Fetal hemoglobin") (α2γ2)

_pathology:_

- [HbH](/wiki/Alpha-thalassemia "Alpha-thalassemia") (β4)
- [Barts](/wiki/Hemoglobin_Barts "Hemoglobin Barts") (γ4)
- [HbD](/wiki/HbD "HbD") (α2βD2)
- [HbS](/wiki/Sickle_cell_disease "Sickle cell disease") (α2βS2)
- [HbC](/wiki/Hemoglobin_C "Hemoglobin C") (α2βC2)
- [HbE](/wiki/Hemoglobin_E "Hemoglobin E") (α2βE2)
- [HbO](/wiki/Hemoglobin_O "Hemoglobin O") (α2βO2)

Compounds

- [Carboxyhemoglobin](/wiki/Carboxyhemoglobin "Carboxyhemoglobin")
- [Carbaminohemoglobin](/wiki/Carbaminohemoglobin "Carbaminohemoglobin")
- [Oxyhemoglobin](/wiki/Hemoglobin "Hemoglobin")/ [Deoxyhemoglobin](/wiki/Deoxyhemoglobin "Deoxyhemoglobin")
- [Sulfhemoglobin](/wiki/Sulfhemoglobinemia "Sulfhemoglobinemia")

Other human

- [Glycated hemoglobin](/wiki/Glycated_hemoglobin "Glycated hemoglobin")
- [Methemoglobin](/wiki/Methemoglobin "Methemoglobin")

Nonhuman

- [Chlorocruorin](/wiki/Erythrocruorin "Erythrocruorin")
- [Erythrocruorin](/wiki/Erythrocruorin "Erythrocruorin")

Other

_human:_

- [Myoglobin](/wiki/Myoglobin "Myoglobin")
  - [Metmyoglobin](/wiki/Metmyoglobin "Metmyoglobin")
- [Neuroglobin](/wiki/Neuroglobin "Neuroglobin")
- [Cytoglobin](/wiki/Cytoglobin "Cytoglobin")

_plant:_

- [Leghemoglobin](/wiki/Leghemoglobin "Leghemoglobin")

Other

- [Cytochrome](/wiki/Cytochrome "Cytochrome")
  - [Cytochrome b](/wiki/Cytochrome_b "Cytochrome b")
  - Cytochrome P450
- [Methemalbumin](/wiki/Methemalbumin "Methemalbumin")

_see also [disorders of globin and globulin proteins](/wiki/Template:Disorders_of_globin_and_globulin_proteins "Template:Disorders of globin and globulin proteins")_

- [v](/wiki/Template:Cytochrome_P450 "Template:Cytochrome P450")
- [t](/wiki/Template_talk:Cytochrome_P450 "Template talk:Cytochrome P450")
- [e](/wiki/Special:EditPage/Template:Cytochrome_P450 "Special:EditPage/Template:Cytochrome P450")

[Cytochromes](/wiki/Cytochrome "Cytochrome"), [oxygenases](/wiki/Oxygenase "Oxygenase"): cytochrome P450 (Most belong to [EC](/wiki/Enzyme_Commission_number "Enzyme Commission number") 1.14)

CYP1

- [A1](/wiki/CYP1A1 "CYP1A1")
- [A2](/wiki/CYP1A2 "CYP1A2")
- [A5](/w/index.php?title=CYP1A5&action=edit&redlink=1 "CYP1A5 (page does not exist)")
- [B1](/wiki/CYP1B1 "CYP1B1")

CYP2

- [A6](/wiki/CYP2A6 "CYP2A6")
- [A7](/wiki/CYP2A7 "CYP2A7")
- [A13](/wiki/CYP2A13 "CYP2A13")
- [B6](/wiki/CYP2B6 "CYP2B6")
- [C8](/wiki/CYP2C8 "CYP2C8")
- [C9](/wiki/CYP2C9 "CYP2C9")
- [C18](/wiki/CYP2C18 "CYP2C18")
- [C19](/wiki/CYP2C19 "CYP2C19")
- [D6](/wiki/CYP2D6 "CYP2D6")
- [E1](/wiki/CYP2E1 "CYP2E1")
- [F1](/wiki/CYP2F1 "CYP2F1")
- [J2](/wiki/CYP2J2 "CYP2J2")
- [R1](/wiki/CYP2R1 "CYP2R1")
- [S1](/wiki/CYP2S1 "CYP2S1")
- [U1](/wiki/CYP2U1 "CYP2U1")
- [W1](/wiki/CYP2W1 "CYP2W1")

CYP3 ( [CYP3A](/wiki/CYP3A "CYP3A"))

- [A4](/wiki/CYP3A4 "CYP3A4")
- [A5](/wiki/CYP3A5 "CYP3A5")
- [A7](/wiki/CYP3A7 "CYP3A7")
- [A37](/w/index.php?title=CYP3A37&action=edit&redlink=1 "CYP3A37 (page does not exist)")
- [A43](/wiki/CYP3A43 "CYP3A43")

CYP4

- [A11](/wiki/CYP4A11 "CYP4A11")
- [A22](/wiki/CYP4A22 "CYP4A22")
- [B1](/wiki/CYP4B1 "CYP4B1")
- [F2](/wiki/CYP4F2 "CYP4F2")
- [F3](/wiki/CYP4F3 "CYP4F3")
- [F8](/wiki/CYP4F8 "CYP4F8")
- [F11](/wiki/CYP4F11 "CYP4F11")
- [F12](/wiki/CYP4F12 "CYP4F12")
- [F22](/wiki/CYP4F22 "CYP4F22")
- [V2](/wiki/CYP4V2 "CYP4V2")
- [X1](/wiki/CYP4X1 "CYP4X1")
- [Z1](/wiki/CYP4Z1 "CYP4Z1")

CYP5-20

- _CYP5_ ( [A1](/wiki/Thromboxane-A_synthase "Thromboxane-A synthase"))
- _[CYP6](/wiki/CYP6_family "CYP6 family")_ ( [G1](/wiki/CYP6G1 "CYP6G1"), [M2](/wiki/CYP6M2 "CYP6M2"))
- _CYP7_ ( [A1](/wiki/Cholesterol_7_alpha-hydroxylase "Cholesterol 7 alpha-hydroxylase"), [B1](/wiki/CYP7B1 "CYP7B1"))
- _CYP8_ ( [A1](/wiki/CYP8A1 "CYP8A1"), [B1](/wiki/CYP8B1 "CYP8B1"))
- _[CYP9](/wiki/CYP9_family "CYP9 family")_
- _[CYP10](/wiki/CYP10_family "CYP10 family")_
- _[CYP11](/wiki/CYP11_family "CYP11 family")_ ( [A1](/wiki/Cholesterol_side-chain_cleavage_enzyme "Cholesterol side-chain cleavage enzyme"), [A2](/wiki/CYP11A2 "CYP11A2"), [B1](/wiki/Steroid_11-beta-hydroxylase "Steroid 11-beta-hydroxylase"), [B2](/wiki/Aldosterone_synthase "Aldosterone synthase"), [B3](/wiki/CYP11B3 "CYP11B3"), [C1](/wiki/CYP11C1 "CYP11C1"))
- _[CYP12](/wiki/CYP12_family "CYP12 family")_
- _[CYP13](/wiki/CYP13_family "CYP13 family")_
- _[CYP14](/wiki/CYP14_family "CYP14 family")_
- _[CYP15](/wiki/CYP15_family "CYP15 family")_
- _[CYP16](/wiki/CYP16_family "CYP16 family")_
- _CYP17_ ( [A1](/wiki/CYP17A1 "CYP17A1"))
- _[CYP18](/wiki/CYP18_family "CYP18 family")_
- _CYP19_ ( [A1](/wiki/Aromatase "Aromatase"))
- _CYP20_ ( [A1](/wiki/CYP20A1 "CYP20A1"))

CYP21-49

- _CYP21_ ( [A2](/wiki/21-Hydroxylase "21-Hydroxylase"))
- _CYP22_ ( [A1](/wiki/Daf-9 "Daf-9"))
- _[CYP23](/wiki/CYP23_family "CYP23 family")_
- _CYP24_ ( [A1](/wiki/CYP24A1 "CYP24A1"))
- _[CYP25](/wiki/CYP25_family "CYP25 family")_
- _[CYP26](/wiki/CYP26_family "CYP26 family")_ ( [A1](/wiki/CYP26A1 "CYP26A1"), [B1](/wiki/CYP26B1 "CYP26B1"), [C1](/wiki/CYP26C1 "CYP26C1"))
- _[CYP27](/wiki/CYP27_family "CYP27 family")_ ( [A1](/wiki/CYP27A1 "CYP27A1"), [B1](/wiki/25-Hydroxyvitamin_D3_1-alpha-hydroxylase "25-Hydroxyvitamin D3 1-alpha-hydroxylase"), [C1](/wiki/CYP27C1 "CYP27C1"))
- _CYP28_ ( [A1](/wiki/CYP28A1 "CYP28A1"))
- _[CYP29](/w/index.php?title=CYP29_family&action=edit&redlink=1 "CYP29 family (page does not exist)")_
- _CYP35_ ( [B1](/wiki/CYP35B1 "CYP35B1"))
- _CYP39_ ( [A1](/wiki/CYP39A1 "CYP39A1"))
- _CYP46_ ( [A1](/wiki/CYP46A1 "CYP46A1"))

CYP51-69

- _[CYP51](/wiki/Sterol_14-demethylase "Sterol 14-demethylase")_ ( [A1](/wiki/Lanosterol_14_alpha-demethylase "Lanosterol 14 alpha-demethylase"), [F1](/wiki/ERG11 "ERG11"))
- _[CYP52](/wiki/CYP52_family "CYP52 family")_
- _[CYP53](/wiki/CYP53_family "CYP53 family")_
  - [A1](/wiki/Benzoate_4-monooxygenase "Benzoate 4-monooxygenase")
- _[CYP55](/wiki/CYP55_family "CYP55 family")_
  - [A1](/wiki/Nitric_oxide_reductase_(NAD(P),_nitrous_oxide-forming) "Nitric oxide reductase (NAD(P), nitrous oxide-forming)")
- _CYP56_
  - [A1](/wiki/CYP56A1 "CYP56A1")
- _[CYP61](/wiki/ERG5 "ERG5")_

CYP71-99

- _CYP71_ ( [C1](/wiki/3-hydroxyindolin-2-one_monooxygenase "3-hydroxyindolin-2-one monooxygenase"), [C2](/wiki/Indolin-2-one_monooxygenase "Indolin-2-one monooxygenase"), [C3](/wiki/2-Hydroxy-1,4-benzoxazin-3-one_monooxygenase "2-Hydroxy-1,4-benzoxazin-3-one monooxygenase"), [C4](/wiki/Indole-2-monooxygenase "Indole-2-monooxygenase"), [Z6](/wiki/Ent-isokaurene_C2-hydroxylase "Ent-isokaurene C2-hydroxylase"), [AJ4](/wiki/Angelicin_synthase "Angelicin synthase"), [AV1](/wiki/Amorpha-4,11-diene_12-monooxygenase "Amorpha-4,11-diene 12-monooxygenase"), [BA1](/wiki/Alpha-humulene_10-hydroxylase "Alpha-humulene 10-hydroxylase"))
- _[CYP72A1](/wiki/Secologanin_synthase "Secologanin synthase")_
- _[CYP73A1](/wiki/Trans-cinnamate_4-monooxygenase "Trans-cinnamate 4-monooxygenase")_
- _[CYP74](/wiki/CYP74_family "CYP74 family")_ ( [D1](/wiki/Colneleate_synthase "Colneleate synthase"))
- _CYP75_ ( [A1](/wiki/Flavonoid_3%27,5%27-hydroxylase "Flavonoid 3',5'-hydroxylase"), [B1](/wiki/Flavonoid_3%27-monooxygenase "Flavonoid 3'-monooxygenase"))
- _[CYP76](/wiki/CYP76_family "CYP76 family")_ ( [B6](/wiki/Geraniol_8-hydroxylase "Geraniol 8-hydroxylase"), [M7](/wiki/Ent-cassa-12,15-diene_11-hydroxylase "Ent-cassa-12,15-diene 11-hydroxylase"))
- _CYP79_ ( [A1](/wiki/Tyrosine_N-monooxygenase "Tyrosine N-monooxygenase"), [A2](/wiki/Phenylalanine_N-monooxygenase "Phenylalanine N-monooxygenase"), [B1](/wiki/Tryptophan_N-monooxygenase "Tryptophan N-monooxygenase"), [B2](/wiki/Tryptophan_N-monooxygenase "Tryptophan N-monooxygenase"), [B3](/wiki/Tryptophan_N-monooxygenase "Tryptophan N-monooxygenase"), [D1](/wiki/Valine_N-monooxygenase "Valine N-monooxygenase"), [D2](/wiki/Valine_N-monooxygenase "Valine N-monooxygenase"), [D3](/wiki/Isoleucine_N-monooxygenase "Isoleucine N-monooxygenase"), [D4](/wiki/Isoleucine_N-monooxygenase "Isoleucine N-monooxygenase"))
- _CYP80_ ( [A1](/wiki/Berbamunine_synthase "Berbamunine synthase"), [B1](/wiki/N-methylcoclaurine_3%27-monooxygenase "N-methylcoclaurine 3'-monooxygenase"), [G2](/wiki/(S)-corytuberine_synthase "(S)-corytuberine synthase"))
- _CYP81_ ( [E1](/wiki/Isoflavone_2%27-hydroxylase "Isoflavone 2'-hydroxylase"), [E3](/wiki/4%27-methoxyisoflavone_2%27-hydroxylase "4'-methoxyisoflavone 2'-hydroxylase"), [E7](/wiki/4%27-methoxyisoflavone_2%27-hydroxylase "4'-methoxyisoflavone 2'-hydroxylase"), [E9](/wiki/Isoflavone_3%27-hydroxylase "Isoflavone 3'-hydroxylase"))
- _[CYP88D6](/wiki/Beta-amyrin_11-oxidase "Beta-amyrin 11-oxidase")_
- _[CYP90C1](/wiki/3-Epi-6-deoxocathasterone_23-monooxygenase "3-Epi-6-deoxocathasterone 23-monooxygenase")_
- _[CYP93E1](/wiki/Beta-amyrin_24-hydroxylase "Beta-amyrin 24-hydroxylase")_
- _[CYP97C1](/wiki/Carotene_epsilon-monooxygenase "Carotene epsilon-monooxygenase")_
- _[CYP99A3](/wiki/9beta-pimara-7,15-diene_oxidase "9beta-pimara-7,15-diene oxidase")_

CYP101-281

- _[CYP101A1](/wiki/Camphor_5-monooxygenase "Camphor 5-monooxygenase")_
- _[CYP102A1](/wiki/Cytochrome_P450_BM3 "Cytochrome P450 BM3")_
- _[CYP105](/wiki/CYP105_family "CYP105 family")_
  - [A1](/wiki/Vitamin_D3_dihydroxylase "Vitamin D3 dihydroxylase")
  - [D7](/wiki/Pentalenic_acid_synthase "Pentalenic acid synthase")
- _[CYP106A2](/wiki/Steroid_15beta-monooxygenase "Steroid 15beta-monooxygenase")_
- _[CYP107](/wiki/CYP107_family "CYP107 family")_
  - [A1](/wiki/Cytochrome_P450_eryF "Cytochrome P450 eryF")
  - [G1](/wiki/CYP107G1 "CYP107G1")
- _[CYP109](/wiki/CYP109_family "CYP109 family")_
  - [B1](/wiki/CYP109B1 "CYP109B1")
  - [E1](/wiki/CYP109E1 "CYP109E1")
- _[CYP111](/wiki/Linalool_8-monooxygenase "Linalool 8-monooxygenase")_
- _[CYP113A1](/wiki/Erythromycin_12_hydroxylase "Erythromycin 12 hydroxylase")_
- _[CYP119A1](/wiki/CYP119A1 "CYP119A1")_
- _[CYP123](/wiki/CYP123_family "CYP123 family")_
- _[CYP125A1](/wiki/Cholest-4-en-3-one_26-monooxygenase "Cholest-4-en-3-one 26-monooxygenase")_
- _[CYP139](/wiki/CYP139_family "CYP139 family")_
- _[CYP147](/wiki/CYP147_family "CYP147 family")_
- _[CYP152](/wiki/Fatty-acid_peroxygenase "Fatty-acid peroxygenase")_
  - A1
  - B1
- _[CYP154C3](/wiki/CYP154C3 "CYP154C3")_
- _[CYP158A](/wiki/Biflaviolin_synthase "Biflaviolin synthase")_
- _[CYP161C](/wiki/Pentalenolactone_synthase "Pentalenolactone synthase")_
- _CYP170_
  - _[A1](/wiki/Epi-isozizaene_5-monooxygenase "Epi-isozizaene 5-monooxygenase")_
  - _[B1](/wiki/CYP170B1 "CYP170B1")_
- _[CYP176A1](/wiki/1,8-Cineole_2-endo-monooxygenase "1,8-Cineole 2-endo-monooxygenase")_
- _[CYP183A](/wiki/Pentalenene_oxygenase "Pentalenene oxygenase")_
- _[CYP197](/wiki/CYP197_family "CYP197 family")_
- _[CYP199A2](/wiki/4-methoxybenzoate_monooxygenase_(O-demethylating) "4-methoxybenzoate monooxygenase (O-demethylating)")_
- _[CYP255A](/wiki/Cytochrome_P450_aromatic_O-demethylase "Cytochrome P450 aromatic O-demethylase")_

CYP301-499

- _[CYP303A1](/wiki/CYP303A1 "CYP303A1")_
- _[CYP305](/wiki/CYP305_family "CYP305 family")_
  - [M2](/wiki/CYP305M2 "CYP305M2")
- [Halloween genes](/wiki/Halloween_genes "Halloween genes") ( _CYP302A1_, _CYP306A1_, _CYP307A1_, _CYP307A2_, _[CYP314A1](/wiki/Ecdysone_20-monooxygenase "Ecdysone 20-monooxygenase")_, _CYP315A1_)
- _[CYP318A1](/wiki/CYP318A1 "CYP318A1")_

CYP501-699

- _[CYP503](/wiki/Ent-kaurene_oxidase "Ent-kaurene oxidase")_
- _[CYP504B1](/wiki/3-hydroxyphenylacetate_6-hydroxylase "3-hydroxyphenylacetate 6-hydroxylase")_

CYP701-999

- _[CYP704B22](/wiki/CYP704B22 "CYP704B22")_
- _[CYP710](/wiki/CYP710_family "CYP710 family")_
- _[CYP720A1](/wiki/Abietadienol_hydroxylase "Abietadienol hydroxylase")_

- [v](/wiki/Template:Enzymes "Template:Enzymes")
- [t](/wiki/Template_talk:Enzymes "Template talk:Enzymes")
- [e](/wiki/Special:EditPage/Template:Enzymes "Special:EditPage/Template:Enzymes")

[Enzymes](/wiki/Enzyme "Enzyme")

Activity

- [Active site](/wiki/Active_site "Active site")
- [Binding site](/wiki/Binding_site "Binding site")
- [Catalytic triad](/wiki/Catalytic_triad "Catalytic triad")
- [Oxyanion hole](/wiki/Oxyanion_hole "Oxyanion hole")
- [Enzyme promiscuity](/wiki/Enzyme_promiscuity "Enzyme promiscuity")
- [Diffusion-limited enzyme](/wiki/Diffusion-limited_enzyme "Diffusion-limited enzyme")
- [Cofactor](/wiki/Cofactor_(biochemistry) "Cofactor (biochemistry)")
- [Enzyme catalysis](/wiki/Enzyme_catalysis "Enzyme catalysis")

Regulation

- [Allosteric regulation](/wiki/Allosteric_regulation "Allosteric regulation")
- [Cooperativity](/wiki/Cooperativity "Cooperativity")
- [Enzyme inhibitor](/wiki/Enzyme_inhibitor "Enzyme inhibitor")
- [Enzyme activator](/wiki/Enzyme_activator "Enzyme activator")

Classification

- [EC number](/wiki/Enzyme_Commission_number "Enzyme Commission number")
- [Enzyme superfamily](/wiki/Protein_superfamily "Protein superfamily")
- [Enzyme family](/wiki/Protein_family "Protein family")
- [List of enzymes](/wiki/List_of_enzymes "List of enzymes")

Kinetics

- [Enzyme kinetics](/wiki/Enzyme_kinetics "Enzyme kinetics")
- [Eadie–Hofstee diagram](/wiki/Eadie%E2%80%93Hofstee_diagram "Eadie–Hofstee diagram")
- [Hanes–Woolf plot](/wiki/Hanes%E2%80%93Woolf_plot "Hanes–Woolf plot")
- [Lineweaver–Burk plot](/wiki/Lineweaver%E2%80%93Burk_plot "Lineweaver–Burk plot")
- [Michaelis–Menten kinetics](/wiki/Michaelis%E2%80%93Menten_kinetics "Michaelis–Menten kinetics")

Types

- **EC1 [Oxidoreductases](/wiki/Oxidoreductase "Oxidoreductase")** ( [list](/wiki/List_of_EC_numbers_(EC_1) "List of EC numbers (EC 1)"))
- **EC2 [Transferases](/wiki/Transferase "Transferase")** ( [list](/wiki/List_of_EC_numbers_(EC_2) "List of EC numbers (EC 2)"))
- **EC3 [Hydrolases](/wiki/Hydrolase "Hydrolase")** ( [list](/wiki/List_of_EC_numbers_(EC_3) "List of EC numbers (EC 3)"))
- **EC4 [Lyases](/wiki/Lyase "Lyase")** ( [list](/wiki/List_of_EC_numbers_(EC_4) "List of EC numbers (EC 4)"))
- **EC5 [Isomerases](/wiki/Isomerase "Isomerase")** ( [list](/wiki/List_of_EC_numbers_(EC_5) "List of EC numbers (EC 5)"))
- **EC6 [Ligases](/wiki/Ligase "Ligase")** ( [list](/wiki/List_of_EC_numbers_(EC_6) "List of EC numbers (EC 6)"))
- **EC7 [Translocases](/wiki/Translocase "Translocase")** ( [list](/wiki/List_of_EC_numbers_(EC_7) "List of EC numbers (EC 7)"))

[Authority control databases](/wiki/Help:Authority_control "Help:Authority control"): National [![Edit this at Wikidata](//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png)](https://www.wikidata.org/wiki/Q407693#identifiers "Edit this at Wikidata")

- [United States](https://id.loc.gov/authorities/sh85035233)
- [France](https://catalogue.bnf.fr/ark:/12148/cb12267061x)
- [BnF data](https://data.bnf.fr/ark:/12148/cb12267061x)
- [Spain](http://catalogo.bne.es/uhtbin/authoritybrowse.cgi?action=display&authority_id=XX544595)
- [Israel](http://olduli.nli.org.il/F/?func=find-b&local_base=NLX10&find_code=UID&request=987007540881805171)

Retrieved from " [https://en.wikipedia.org/w/index.php?title=Cytochrome\_P450&oldid=1243845622](https://en.wikipedia.org/w/index.php?title=Cytochrome_P450&oldid=1243845622)"

[Categories](/wiki/Help:Category "Help:Category"):

- [Cytochrome P450](/wiki/Category:Cytochrome_P450 "Category:Cytochrome P450")
- [EC 1.14](/wiki/Category:EC_1.14 "Category:EC 1.14")
- [Pharmacokinetics](/wiki/Category:Pharmacokinetics "Category:Pharmacokinetics")
- [Metabolism](/wiki/Category:Metabolism "Category:Metabolism")
- [Integral membrane proteins](/wiki/Category:Integral_membrane_proteins "Category:Integral membrane proteins")

Hidden categories:

- [Webarchive template wayback links](/wiki/Category:Webarchive_template_wayback_links "Category:Webarchive template wayback links")
- [CS1: long volume value](/wiki/Category:CS1:_long_volume_value "Category:CS1: long volume value")
- [Articles with short description](/wiki/Category:Articles_with_short_description "Category:Articles with short description")
- [Short description is different from Wikidata](/wiki/Category:Short_description_is_different_from_Wikidata "Category:Short description is different from Wikidata")

- This page was last edited on 3 September 2024, at 19:11 (UTC).
- Text is available under the [Creative Commons Attribution-ShareAlike License 4.0](//en.wikipedia.org/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License);
additional terms may apply. By using this site, you agree to the [Terms of Use](//foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use) and [Privacy Policy](//foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy). Wikipedia® is a registered trademark of the [Wikimedia Foundation, Inc.](//wikimediafoundation.org/), a non-profit organization.

- [Privacy policy](https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy)
- [About Wikipedia](/wiki/Wikipedia:About)
- [Disclaimers](/wiki/Wikipedia:General_disclaimer)
- [Contact Wikipedia](//en.wikipedia.org/wiki/Wikipedia:Contact_us)
- [Code of Conduct](https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct)
- [Developers](https://developer.wikimedia.org)
- [Statistics](https://stats.wikimedia.org/#/en.wikipedia.org)
- [Cookie statement](https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement)
- [Mobile view](//en.m.wikipedia.org/w/index.php?title=Cytochrome_P450&mobileaction=toggle_view_mobile)

- [![Wikimedia Foundation](/static/images/footer/wikimedia-button.svg)](https://wikimediafoundation.org/)
- [![Powered by MediaWiki](/w/resources/assets/poweredby_mediawiki.svg)](https://www.mediawiki.org/)