Related Research Articles
Sulfur-reducing bacteria are microorganisms able to reduce elemental sulfur (S0) to hydrogen sulfide (H2S). These microbes use inorganic sulfur compounds as electron acceptors to sustain several activities such as respiration, conserving energy and growth, in absence of oxygen. The final product or these processes, sulfide, has a considerable influence on the chemistry of the environment and, in addition, is used as electron donor for a large variety of microbial metabolisms. Several types of bacteria and many non-methanogenic archaea can reduce sulfur.Microbial sulfur reduction was already shown in early studies, which highlighted the first proof of S0 reduction in a vibrioid bacterium from mud, with sulfur as electron acceptor and H2 as electron donor. The first pure cultured species of sulfur-reducing bacteria, Desulfuromonas acetoxidans, was discovered in 1976 and described by Pfennig Norbert and Biebel Hanno as an anaerobic sulfur-reducing and acetate-oxidizing bacterium, not able to reduce sulfate. Only few taxa are true sulfur-reducing bacteria, using sulfur reduction as the only or main catabolic reaction. Normally, they couple this reaction with the oxidation of acetate, succinate or other organic compounds.In general, sulfate-reducing bacteria, are able to use both sulfate and elemental sulfur as electron acceptors. Thanks to its abundancy and thermodynamic stability, sulfate is the most studied electron acceptor for anaerobic respiration that involves sulfur compounds. Elemental sulfur, however, is very abundant and important, especially in deep-sea hydrothermal vents, hot springs and other extreme environments, making its isolation more difficult. Some bacteria – such as Proteus, Campylobacter, Pseudomonas and Salmonella – have the ability to reduce sulfur, but can also use oxygen and other terminal electron acceptors.
In biology, syntrophy, synthrophy, or cross-feeding is the phenomenon of one species living off of the metabolic products of another species. In this type of biological interaction, the growth of one partner depends on the nutrients, growth factors, or substrates provided by the other partner. Jan Dolfing describes syntrophy as "the critical interdependency between producer and consumer". This term for nutritional interdependence is often used in microbiology to describe this symbiotic relationship between bacterial species. Morris et al. have described the process as "obligately mutualistic metabolism".
Hydrogenobacter thermophilus is an extremely thermophilic, straight rod (bacillus) bacterium. TK-6 is the type strain for this species. It is a Gram negative, non-motile, obligate chemolithoautotroph. It belongs to one of the earliest branching order of Bacteria. H. thermophilus TK-6 lives in soil that contains hot water. It was one of the first hydrogen oxidizing bacteria described leading to the discovery, and subsequent examination of many unique proteins involved in its metabolism. Its discovery contradicted the idea that no obligate hydrogen oxidizing bacteria existed, leading to a new understanding of this physiological group. Additionally, H. thermophilus contains a fatty acid composition that had not been observed before.
Syntrophobacter sulfatireducens is a species of bacteria notable for degrading propionate. It is notable for being syntrophic and for oxidising propionate. Its cells are egg-shaped. TB8106T is its type strain.
Syntrophomonas wolfei is a bacterium. It is anaerobic, syntrophic and fatty acid-oxidizing. It has a multilayered cell wall of the gram-negative type.
Thermacetogenium phaeum is a bacterium, the type species of its genus. It is strictly anaerobic, thermophilic, syntrophic and acetate-oxidizing. Its cells are gram-positive, endospore-forming and rod-shaped. Its type strain is PBT. It has a potential biotechnological role.
Clostridium uliginosum is a mesophilic bacterium oxidizing acetate in syntrophic association with a hydrogenotrophic methanogenic bacterium. It is a spore-forming, gram-positive, rod-shaped organism, with type strain BST. Its genome has been sequenced.
Syntrophomonas curvata is a bacterium. It is anaerobic, syntrophic and fatty acid-oxidizing. Its type strain is GB8-1T.
Syntrophomonas palmitatica is a bacterium. It is anaerobic, syntrophic and fatty acid-oxidizing. Its type strain is GB8-1T. Cells are slightly curved, non-motile rods.
Syntrophomonas zehnderi is a bacterium. It is anaerobic, syntrophic and fatty acid-oxidizing. The type strain is OL-4T. Cells are slightly curved, non-motile rods.
Syntrophobacter fumaroxidans is a species of syntrophic propionate-degrading sulfate-reducing bacterium. Strain MPOBT is the type strain. Its genome has been fully sequenced.
"Syntrophothermus lipocalidus" is a bacterium, the type species and only currently described species in its genus. It is thermophilic, syntrophic, fatty-acid-oxidizing and anaerobic, and utilises isobutyrate. TGB-C1T is its type strain. Its genome has been fully sequenced.
Syntrophobacter pfennigii is a species of syntrophic propionate-oxidising anaerobic bacterium. Strain KoProp1 is the type strain.
Smithella propionica is a species of bacteria, the type species of its genus. It is anaerobic, syntrophic, propionate-oxidizing bacteria, with type strain LYPT.
Thermosyntropha lipolytica is a lipolytic, anaerobic, alkalitolerant, thermophilic bacteria. It lives in syntrophic coculture with a methanogen. Its cells are non-motile, non-spore forming, straight or slightly curved rods. Its type strain is JW/VS-265T.
Thermosinus carboxydivorans is an anaerobic, thermophilic, Gram-negative, carbon-monoxide-oxidizing, hydrogenogenic bacterium, the type species of its genus. It is facultatively carboxydotrophic, curved, motile, rod-shaped, with a length of 2.6–3 μm, a width of about 0.5 μm and lateral flagellation. Its type strain is Nor1T.
Opitutus terrae is an obligately anaerobic bacterium first isolated from rice paddy soil, hence its epithet. It is coccus-shaped and is motile by means of a flagellum. Its type strain is PB90-1T. Its genome has been sequenced.
Clostridium straminisolvens is a moderately thermophilic, aerotolerant and cellulolytic bacterium. It is non-motile, spore-forming, straight or slightly curved rod, with type strain CSK1T. Its genome has been sequenced.
Syntrophaceticus schinkii is a species of strictly anaerobic, mesophilic, endospore-forming, syntrophic, acetate-oxidizing bacterium, the type species of its genus. Its type strain is Sp3T, which was isolated from an anaerobic filter treating wastewater in a fishmeal factory.
Pelotomaculum is a Gram-positive strictly anaerobic, mesophilic, thermophilic and non-motile bacterial genus from the family of Peptococcaceae.
