Desulfobacter

A Microbial Biorealm page on the genus Desulfobacter

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Classification

Higher order taxa:

Bacteria; Proteobacteria; delta/epsilon subdivisions; Deltaproteobacteria; Desulfobacterales; Desulfobacteraceae

Species:

NCBI: Taxonomy Genome

D. postgatei, D. hydrogenophilus, D. latus, and D. curvatus

Description and Significance

Desulfobacter is a mesophilic gram-negative genera that is capable of oxidizing organic substrate completely to CO2 in anoxic codition. Desulfobacter is mainly found in brackish and marine environemnt and has a oval or vibrio morphology [1]. The genus desulfobacter includes acetateutelizing sulphate-reducing bacteria. 10 Methyl 16:0 is an unusual bacterial phospholipid fatty acids (PLFA) characteristic of Desulfobacter-type sulphate-reducing bacteria and could be used as a biomarker for these bacteria [2,3].

Cell Structure and Metabolism

D. variabilis contains significant quantities of AEG-P (top), and almost 20% of the alkyl-glycerol bond is present as DPG lipids, also known as "cardiolipin" (bottom). Note that the DPGs contain either ether or ester linkages in the core lipids.Sturt et al

Sulfate reducers have a wide range of cellular morphologies, including rods, vibrios, ovals, spheres and even tear-dropped or onion shaped cells. Some are motile, others are not. Most sulfate-reducing bacteria are mesophilic, but a few thermophiles are known. Desulfosarcina variabilis is mesophilic, and contains bacterial core lipids (see images on left). The dominant phospholipid headgroups in D. variabilis are Phosphoethanolamine PE (48%) and Phosphoglycerol PG (33%). One study has found that Desulfosarcina variabilis solely contained n-hexadecyl ether side chains. For more information on tetraether lipids found in Archaea, click here.

Ecology

Micobiological and molecular studies have suggested the presence of different sulfate reducing bacteria (SBR)in oxic and anoxic layers of soil profile. Dsulfobater, Desulfobulbus and desulfotomoculum species were detected in restricly anoxic conition while Desulfococcus, Desolfonema, and Desulfovibrio species appear to be perdominantly in oxic layers [4]. The main habitat of Desulfobacter is marine sendiment and brackish water.

The Plum Island Estuary Microbial Observatory (PIMO), located at the Plum Island Estuary LTER site in coastal Massachusetts, identifies prokaryotes in salt marsh sediments and plankton and determines their role in controlling major ecosystem processes. Among SRBs identified, relatives of Desulfosarcina variabilis and Desulfobacterium anilini were found to be persistent in the sediment.

References

Arches, specifically p.10 populations and methods.PDF here.

[http://www.bact.wisc.edu/Microtextbook/modules.php?op=modload&name=Sections&file=index&req=viewarticle&artid=104&page=1 Microbiology Textbook. Copyright, Timothy Paustian© 1999-2004.]

[1] Lary L. Barton Biotechnology handbooks. Vol. 8-Sulfate reducing bacteria. 1995 Plenum Press, New York.

[2] Dowling, N.J., Widdel, F. and White, D.C. (1986) Comparison of the phospholipid ester-linked fatty acid biomarkers of acetate-oxidising sulphate-reducers and other sulphide-forming bacteria. J. Gen. Microbiol. 132,1815-1825.

[3] Dowling, N.J., Nichols, P.D. and White, D.C. (1988)Phospholipid fatty acid and infra-red spectroscopic analysis of a sulfate-reducing consortium. FEMS Microbiol.Ecol. 53, 325-334.

[4] Sulphate reducing bacteria-book)

Rutters H, Sass H, Cypionka H, Rullkotter J. "Monoalkylether phospholipids in the sulfate-reducing bacteria Desulfosarcina variabilis and Desulforhabdus amnigenus." Arch Microbiol. 2001 Dec;176(6):435-442. Epub 2001 Sep 19.

Santegoeds, Cecilia M.; Timothy G. Ferdelman, Gerard Muyzer, and Dirk de Beer. "Structural and Functional Dynamics of Sulfate-Reducing Populations in Bacterial Biofilms." Appl Environ Microbiol. 1998 October; 64(10): 3731–3739. Copyright © 1998, American Society for Microbiology.

Sturt, Helen F.; Roger E. Summons, Kristin Smith, Marcus Elvert, and Kai-Uwe Hinrichs. "Intact polar membrane lipids in prokaryotes and sediments deciphered by high-performance liquid chromatography/electrospray ionization multistage mass spectrometry—new biomarkers for biogeochemistry and microbial ecology." Rapid Commun. Mass Spectrom. 2004; 18: 617–628.