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.
Delftia is a genus of Gram-negative bacteria that was first isolated from soil in Delft, Netherlands. The species is named after both the city, and in honor of pioneering research in the field of bacteriology that occurred in Delft. Cells in the genus Delftia are rod shaped and straight or slightly curved. Cells occur singly or in pairs, are 0.4–0.8ɥM wide and 2.5–4.1 μm long. Delftia species are motile by flagella, nonsporulating, and chemo-organotrophic.
Delftia acidovorans is a Gram-negative, motile, non-sporulating, rod-shaped bacterium known for its ability to biomineralize gold and bioremediation characteristics. It was first isolated from soil in Delft, Netherlands. The bacterium was originally categorized as Pseudomonas acidovorans and Comamonas acidovorans before being reclassified as Delftia acidovorans.
Delftia tsuruhatensis is a Gram-negative, rod-shaped, catalase- and oxidase-positive, motile bacterium from the Comamonadaceae family. It was first isolated from a wastewater treatment plant in Japan in 2003. D. tsuruhatensis is an opportunistic and emergent pathogen. All documented human infections are healthcare-associated.
Delftia lacustris is a Gram-negative, nonfermentative, motile, rod-shaped bacterium from the family Comamonadaceae, which was isolated from mesotrophic lake water in Denmark. It has the ability to degrade peptidoglycan through chitinase and lysozyme activity.
Arthrobacter deserti is a Gram-positive, rod-shaped and non-motile bacterium species from the genus Arthrobacter which has been isolated from desert soil from the Turpan desert in China. The type strain for this specific bacterium is YIM CS25T. Arthrobacter deserti contains lysine in its peptidoglycan layer. This species of Arthrobacter is aerobic. The cells were non-sporulating and rod-to-coccus shaped. The cells are known to use at least 36 different types of carbon sources. The predominant menaquinone is MK-9(H2). The genomic DNA G+C content of the type strain is 68.3 mol%.
Microvirga soli is a Gram-negative, methanol-utilizing, rod-shaped and non-spore-forming bacterium from the genus of Microvirga which has been isolated from forest soil from Sichuan in China.
Saccharopolyspora cavernae is a Gram-positive, aerobic and non-motile bacterium from the genus of Saccharopolyspora which has been isolated from cave-wall soil from the Swallow Cave, Yunnan Province, China.
Hymenobacter mucosus is a Gram-negative, rod-shaped and non-motile bacterium from the genus Hymenobacter which has been isolated from soil from the Jiuxiang cave in China. It produces red, watermelonlike pigment from the plectaniaxanthin series of carotenoid pigments. The 16S RNA analysis has revealed its similarity to Hymenobacter tibetensis, Hymenobacter gelipurpurascens and Hymenobacter xinjiangensis
Caenispirillum deserti is a Gram-negative, Vibrio-shaped, aerobic, spheroplast-forming and motile bacterium from the genus of Caenispirillum which has been isolated from the salt desert in Kutch in India.
Aquamicrobium soli is a Gram-negative, aerobic, short rod-shaped non-spore-forming and non-motile bacteria from the genus of Aquamicrobium which has been isolated from soil which was contaminated with chlorobenzoate in China.
Microvirga pakistanensis is a Gram-negative, non-spore-forming, strictly aerobic and non-motile bacterium from the genus of Microvirga which has been isolated from desert soil from Cholistan desert in Pakistan.
Falsirhodobacter deserti is a Gram-negative, aerobic, halotolerant, heterotrophic and non-motile bacteria bacterium from the genus of Falsirhodobacter which has been isolated from the desert of Xinjiang in China.
Phenylobacterium terrae is a Gram negative, aerobic, non-spore-forming, rod-shaped and motile bacterium from the genus of Phenylobacterium which has been isolated from soil from Khyber Pakhtun Khwa in Pakistan.
Phenylobacterium deserti is a Gram negative, aerobic and motile bacterium from the genus of Phenylobacterium which has been isolated from desert soil from the Cholistan Desert in Pakistan.
Alishewanella solinquinati is a Gram-negative, facultative anaerobic, rod-shaped and motile bacterium from the genus of Alishewanella.
Parapedobacter deserti is a Gram-negative, non-spore-forming, rod-shaped and non-motile bacterium from the genus of Parapedobacter which has been isolated from the stem of the plant Haloxylon ammodendron.
Chryseomicrobium deserti is a Gram-positive, rod-shaped, aerobic, and non-motile bacterium from the genus of Chryseomicrobium which has been isolated from desert soil from Korea.
Pseudoclavibacter endophyticus is a Gram-positive, aerobic, rod-shaped and non-motile bacterium from the genus Pseudoclavibacter which has been isolated from the roots of the plant Glycyrrhiza uralensis from Yili County in China.
Virgibacillus litoralis is a Gram-positive, moderately halophilic, endospore-forming, aerobic, rod-shaped and motile bacterium from the genus of Virgibacillus which has been isolated from saline soil.
