Green sulfur bacteria

Green sulfur bacteria
Green sulfur bacteria in a Winogradsky column
Scientific classification
Domain: Bacteria
Phylum: Chlorobi

Class Chlorobea Cavalier-Smith 2002
  Order Chlorobiales Gibbons and Murray 1978
    Family Chlorobiaceae Copeland 1956
      Ancalochloris Gorlenko and Lebedeva 1971
      Chlorobaculum Imhoff 2003
      Chlorobium Nadson 1906 emend. Imhoff 2003
      Chloroherpeton Gibson et al. 1985
      Clathrochloris Witt et al. 1989
      Pelodictyon Lauterborn 1913
      Prosthecochloris Gorlenko 1970 emend. Imhoff 2003
Class Ignavibacteria Iino et al. 2010
  Order Ignavibacteriales Iino et al. 2010
    Family Ignavibacteriaceae Iino et al. 2010
      Ignavibacterium Iino et al. 2010

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.[1]

Green sulfur bacteria are non-motile (except Chloroherpeton thalassium, which may glide)[1] and come in spheres, rods, and spirals. Photosynthesis is achieved using bacteriochlorophyll (BChl) c, d, or e, in addition to BChl a and chlorophyll a,[1] in chlorosomes attached to the membrane. 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 electron donor and produces oxygen.[1]

Chlorobium tepidum has emerged as a model organism for the group, and although only ten 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 that these organisms are adapted to a narrow range of energy-limited conditions, an ecology shared with the simpler cyanobacteria, Prochlorococcus and Synechococcus[1]

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 meters beneath the surface of 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.[2]

Green sulfur bacteria appear in Lake Matano, Indonesia, at a depth of approximately 110–120 meters. The population may include the species, Chlorobium ferrooxidans.[3]

Contents

See also

Phylogeny

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LSPN) [4] [5] and the phylogeny is based on 16S rRNA-based LTP release 106 by The All-Species Living Tree Project [6]



Ignavibacterium album Iino et al. 2010


  Chlorobiaceae

?Ancalochloris perfilieviiGorlenko and Lebedeva 1971



?Clathrochloris sulfuricaWitt et al. 1989



?Pelodictyon phaeum Gorlenko 1972



Chloroherpeton thalassium Gibson et al. 1985



  Prosthecochloris

?P. aphaeoasteroides



?P. indicaAnil 2005



P. aestuarii Gorlenko 1970 emend. Imhoff 2003



P. vibrioformis (Pelsh 1936) Imhoff 2003





Chlorobium chlorovibrioides(Gorlenko et al. 1974) Imhoff 2003



  Chlorobaculum

?C. limnaeum Imhoff 2003



?C. macestaeKeppen et al. 2008



?C. parvum Imhoff 2003



C. tepidum (Wahlund et al. 1996) Imhoff 2003



C. thiosulfatiphilum Imhoff 2003



  Chlorobium

?C. bathyomarinumBeatty et al. 2005



?C. chlorochromatiiVogl et al. 2006 (epibiont of the phototrophic consortium Chlorochromatium aggregatum)



?C. gokarnaAnil 2005



?C. ferrooxidans Heising et al. 1998 emend. Imhoff 2003



C. luteolum (Schmidle 1901) emend. Imhoff 2003




C. phaeovibrioides Pfennig 1968 emend. Imhoff 2003




C. limicola Nadson 1906 emend. Imhoff 2003




C. clathratiforme (Szafer 1911) emend. Imhoff 2003



C. phaeobacteroides Pfennig 1968 emend. Imhoff 2003











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
♥ 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)

Notes, links and References

External links

References

  1. ^ a b c d e D.A. Bryant & N.-U. Frigaard (November 2006). "Prokaryotic photosynthesis and hototrophy illuminated". Trends Microbiol. 14 (11): 488–96. doi:10.1016/j.tim.2006.09.001. PMID 16997562. 
  2. ^ Beatty JT, Overmann J, Lince MT, Manske AK, Lang AS, Blankenship RE, Van Dover CL, Martinson TA, Plumley FG. (2005). "An obligately photosynthetic bacterial anaerobe from a deep-sea hydrothermal vent". Proc. Natl Acad. Sci. USA 102 (26): 9306–10. doi:10.1073/pnas.0503674102. PMC 1166624. PMID 15967984. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1166624. 
  3. ^ Crowe, Sean; Jones, CarriAyne; Katsev, Sergei; et al., C; O'Neill, AH; Sturm, A; Canfield, DE; Haffner, GD et al. (2008). "Photoferrotrophs thrive in an Archean Ocean analogue". Proceedings of the National Academy of Sciences 105 (41): pp. 15938–43. 2008-10-14. doi:10.1073/pnas.0805313105. ISSN 0148-0227. PMC 2572968. PMID 18838679. http://www.pnas.org/content/105/41/15938.full. Retrieved 2009-06-30 
  4. ^ See the List of Prokaryotic names with Standing in Nomenclature. Data extracted from J.P. Euzéby. "Chlorobi". http://www.bacterio.cict.fr/classifphyla.html#Chlorobi. Retrieved 2011-11-17. 
  5. ^ See the NCBI webpage on Chlorobi Data extracted from Sayers et al.. "NCBI Taxonomy Browser". National Center for Biotechnology Information. http://www.ncbi.nlm.nih.gov/Taxonomy/taxonomyhome.html/index.cgi. Retrieved 2011-06-05. 
  6. ^ See the All-Species Living Tree Project [1]. Data extracted from the "16S rRNA-based LTP release 106 (full tree)". Silva Comprehensive Ribosomal RNA Database. http://www.arb-silva.de/fileadmin/silva_databases/living_tree/LTP_release_106/LTPs106_SSU_tree.pdf. Retrieved 2011-11-17.