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The green sulfur bacteria are a family of obligately anaerobic photoautotrophic bacteria. Most closely related to the distant Bacteroidetes, they are accordingly assigned their own phylum. Green sulfur bacteria are nonmotile (except ''Chloroherpeton thalassium'', which may glide)〔 and occur in spheres, rods, and spirals. Photosynthesis is achieved using a Type 1 Reaction Centre using bacteriochlorophyll (BChl) ''a'' and in chlorosomes which employ BChl ''c'', ''d'', or ''e''; in addition chlorophyll ''a'' is also present,.〔 They use sulfide ions, hydrogen or ferrous iron as an electron donor and the process is mediated by the type I reaction centre and Fenna-Matthews-Olson complex. Elemental sulfur deposited outside the cell may be further oxidized. By contrast, the photosynthesis in plants uses water as the electron donor and produces oxygen.〔 ''Chlorobium tepidum'' has emerged as a model organism for the group; although only 10 genomes have been sequenced, these are quite comprehensive of the family's biodiversity. Their 2-3 Mb genomes encode 1750-2800 genes, 1400-1500 of which are common to all strains. The apparent absence of two-component histidine-kinases and response regulators suggest limited phenotypic plasticity. Their small dependence on organic molecule transporters and transcription factors also indicate these organisms are adapted to a narrow range of energy-limited conditions, an ecology shared with the simpler cyanobacteria, ''Prochlorococcus'' and ''Synechococcus''〔 A species of green sulfur bacteria has been found living near a black smoker off the coast of Mexico at a depth of 2,500 m in the Pacific Ocean. At this depth, the bacterium, designated GSB1, lives off the dim glow of the thermal vent since no sunlight can penetrate to that depth.〔 〕 Green sulfur bacteria appear in Lake Matano, Indonesia, at a depth of about 110–120 m. The population may include the species ''Chlorobium ferrooxidans''.〔 〕 ==Phylogeny== The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN) 〔See the List of Prokaryotic names with Standing in Nomenclature. Data extracted from (【引用サイトリンク】 url=http://www.bacterio.cict.fr/classifphyla.html#Chlorobi )〕 〔See the NCBI (webpage on Chlorobi ) Data extracted from 〕 and the phylogeny is based on 16S rRNA-based LTP release 111 by The All-Species Living Tree Project 〔See the All-Species Living Tree Project (). Data extracted from the (【引用サイトリンク】 title=16S rRNA-based LTP release 111 (full tree) )〕 |label2=''Chlorobium'' |2= }} }} }} }} }} }} }} Notes: ♪ Prokaryotes where no pure (axenic) cultures are isolated or available, i. e. not cultivated or can not be sustained in culture for more than a few serial passages ♦ Type strain lost or not available ♥ Strains not lodged at National Center for Biotechnology Information (NCBI) or listed in the List of Prokaryotic names with Standing in Nomenclature (LPSN) ♠ Strains found at the National Center for Biotechnology Information (NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature (LSPN) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Green sulfur bacteria」の詳細全文を読む スポンサード リンク
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