The Hydrogenophilaceae are a family of the class Hydrogenophilalia in the phylum Pseudomonadota ("Proteobacteria"), with two genera – Hydrogenophilus and Tepidiphilus. Like all Pseudomonadota, they are Gram-negative. All known species are thermophilic, growing around 50 °C, and use molecular hydrogen or organic molecules as their source of electrons to support growth; some species are autotrophs.
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.
The Alicyclobacillaceae are a family of Gram-positive bacteria. All members of this family are aerobic and form endospores.
Acidovorax facilis is an aerobic, chemoorganotrophic bacterium used as a soil inoculant in agriculture and horticulture.
Thermoanaerobacter is a genus in the phylum Bacillota (Bacteria). Members of this genus are thermophilic and anaerobic, several of them were previously described as Clostridium species and members of the now obsolete genera Acetogenium and Thermobacteroides
Thermoanaerobacter ethanolicus is a species of thermophilic, anaerobic, non-spore-forming bacteria.
Coprothermobacter proteolyticus, formerly Thermobacteroides proteolyticus, is a thermophilic, non-spore-forming bacteria.
Thermoanaerobacter brockii, formerly Thermoanaerobium brockii, is a thermophilic, anaerobic, spore-forming bacterium.
Thermoanaerobacter kivui is a thermophilic, anaerobic, nonspore-forming species of bacteria.
Thermoanaerobacter mathranii is a thermophilic, anaerobic, spore-forming bacteria.
Thermoanaerobacter pseudethanolicus is a thermophilic, strictly anaerobic, spore-forming bacteria that was first found at Yellowstone National Park in the United States. Because of its ability to efficiently ferment sugars, it is thought to be of potential use in producing industrial alcohol.
Caldanaerobacter is a Gram-positive or negative and strictly anaerobic genus of bacteria from the family of Thermoanaerobacteraceae.
The genus Annwoodia was named in 2017 to circumscribe an organism previously described as a member of the genus Thiobacillus, Thiobacillus aquaesulis - the type and only species is Annwoodia aquaesulis, which was isolated from the geothermal waters of the Roman Baths in the city of Bath in the United Kingdom by Ann P. Wood and Donovan P. Kelly of the University of Warwick - the genus was subsequently named to honour Wood's contribution to microbiology. The genus falls within the family Thiobacillaceae along with Thiobacillus and Sulfuritortus, both of which comprise autotrophic organisms dependent on thiosulfate, other sulfur oxyanions and sulfide as electron donors for chemolithoheterotrophic growth. Whilst Annwoodia spp. and Sulfuritortus spp. are thermophilic, Thiobacillus spp. are mesophilic.
Coprothermobacterota is a phylum of nonmotile, rod-shaped bacteria.
Coprothermobacterales is a taxonomic order of thermophilic bacteria in the class Coprothermobacteria of the phylum Coprothermobacterota.
Coprothermobacteraceae is a bacterial family of rod-shaped microorganisms, belonging to the order Coprothermobacterales, class Coprothermobacteria of the phylum Coprothermobacterota.
Coprothermobacter is a genus of rod-shaped microorganisms, belonging to the bacterial family Coprothermobacteraceae of the phylum Coprothermobacterota. This taxonomic genus has been reclassified in 2018, after different phylogenetic studies showed that these bacteria represented a deeply branched taxon of the domain Bacteria; consequently, the clade including this genus has been classified in a separate phylum from Firmicutes, the phylum where it was included before reclassification.
Coprothermobacter platensis is a species of moderately thermophilic and strictly anaerobic bacterium belonging to the family Coprothermobacteraceae within the phylum Coprothermobacterota.
Effusibacillus pohliae is a species of Gram positive, aerobic, thermophilic bacterium. The cells are rod-shaped and form spores. It was first isolated from Mount Melbourne, Antarctica. The species is named after the genus of Pohlia nutans, a species of moss that was colonizing the area where the type strain was isolated. E. pohliae has also been isolated from a geothermal heat pump in South Korea.
