Chlorosome shape can vary between species, with some species containing ellipsoidal shaped chlorosomes and others containing conical or irregular shaped chlorosomes.[2] Inside green sulfur bacteria, the chlorosomes are attached to type-I reaction centers in the cell membrane via FMO-proteins and a chlorosome baseplate composed of CsmA proteins.[2] Filamentous anoxygenic phototrophs of the phylum Chloroflexi lack the FMO complex, but instead use a protein complex called B808-866.