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 of 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 H
2 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 feeding on the metabolic products of another species to cope up with the energy limitations by electron transfer. In this type of biological interaction, metabolite transfer happens between two or more metabolically diverse microbial species that live in close proximity to each other. The growth of one partner depends on the nutrients, growth factors, or substrates provided by the other partner. Thus, syntrophism can be considered as an obligatory interdependency and a mutualistic metabolism between two different bacterial species.
Methanothrix soehngenii is a species of methanogenic archaea. Its cells are non-motile, non-spore-forming, rod-shaped and are normally combined end to end in long filaments, surrounded by a sheath-like structure. It is named in honour of N. L. Söhngen.
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.
Syntrophus buswellii is a bacterium. It is a motile, gram-negative, anaerobic rod-shaped organism which catabolises benzoate.
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 sapovorans is a bacterium. It is anaerobic, syntrophic, and fatty acid-oxidizing and obligately proton-reducing. Its type strain is OM. It has a doubling time of 40 hours. It is part of the family Syntrophomonadaceae based on comparative small-subunit (SSU) rRNA sequence analysis. This family currently contains three genera, Syntrophomonas, Syntrophospora, and Thermosyntropha, as well as two closely related isolates, strains FSM2 and FSS7.
Syntrophomonas curvata is a bacterium. It is anaerobic, syntrophic and fatty acid-oxidizing. Its type strain is GB8-1T.
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.
"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.
Pelotomaculum thermopropionicum is an anaerobic, thermophilic, syntrophic propionate-oxidizing bacterium, the type species of its genus. The type strain is strain SI(T).
Syntrophus aciditrophicus is a gram-negative and rod-shaped bacterium. It is non-motile, non-spore-forming and grows under strictly anaerobic conditions, thus an obligate anaerobe. It degrades fatty acids and benzoate in syntrophic association with hydrogen-using microorganisms. Its genome was published in 2007.
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.
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.
Tepidanaerobacter is a genus of anaerobic, moderately thermophilic, syntrophic bacteria from the family Tepidanaerobacteraceae.
Tepidanaerobacter acetatoxydans is an anaerobic bacterium from the genus of Tepidanaerobacter.
References
- ↑ Hatamoto, M.; Imachi, H.; Fukayo, S.; Ohashi, A.; Harada, H. (2007). "Syntrophomonas palmitatica sp. nov., an anaerobic, syntrophic, long-chain fatty-acid-oxidizing bacterium isolated from methanogenic sludge". International Journal of Systematic and Evolutionary Microbiology. 57 (9): 2137–2142. doi: 10.1099/ijs.0.64981-0 . ISSN 1466-5026. PMID 17766887.
