D esulfovibrio

Abstract

Abstract De.sul.fo.vi'bri.o. L. pref. de from; L. neut. n. sulfur sulfur; L. v. vibrio to vibrate; N.L. masc. n. Vibrio that which vibrates, a generic name; N.L. masc. n. Desulfovibrio a vibrio that reduces sulfur compounds. Desulfobacterota / Desulfovibrionia / Desulfovibrionales / Desulfovibrionaceae / Desulfovibrio Curved or occasionally straight rods, sometimes sigmoid or spirilloid, 0.4–1.3 × 0.8–5.0 µm. The morphology is influenced by age and environment; descriptions refer to freshly grown cultures in anoxic sulfate media. Spore formation is absent. Stain Gram‐negative. Motile by means of a single polar flagellum or immotile (one species). Obligately anaerobic growth in pure cultures. Strictly anaerobic, having both a respiratory and a fermentative type of metabolism. Chemoorganoheterotrophs, using lactate, pyruvate, some species fumarate, succinate, and malate as electron donors and carbon sources; organic compounds are incompletely oxidized to acetate. Alcohols are oxidized to their corresponding acids. H 2 can be used as an electron donor in the presence of acetate as organic carbon source (chemolithoheterotrophic growth). Formate can be used in the presence of acetate. Sulfate, sulfite, and often thiosulfate serve as terminal electron acceptors and are reduced to H 2 S. Some species can reduce oxygen or metal ions, but growth has never been observed with these electron acceptors in pure cultures. Nitrate is sometimes reduced to ammonia. In the absence of an external electron acceptor, growth may occur by fermentation of pyruvate, malate, or fumarate. Molecular nitrogen is sometimes assimilated. Mesophilic; the optimum temperature range for growth is 30–38°C. Media containing a reductant are required for growth; some species need vitamins. Cells contain c ‐type cytochromes (such as c 3 ) and usually b ‐type cytochromes. All members of the genus Desulfovibrio contain desulfoviridin. Occur in anoxic parts of fresh and brackish water and marine environments; intestines of animals; manure; and feces. DNA G + C content (mol%) : 48.0–63.1 ( T m , LC, genome). Type species : Desulfovibrio desulfuricans (Beijerinck 1895) Kluyver and van Niel 1936, 397 AL ( Spirillum desulfuricans Beijerinck 1895, 113).