Sulfate respiring bacteria

In benthic environments, ranging from the rhizosphere of shallow water macrophyte communities such as Zostera, Thalassia and Spartim hundreds of different diazotrophic strains have been isolated, and these are typically microaerophyUic or anaerobic, and often are sulfate respiring bacteria. These diazotrophs make significant contributions to the nitrogen economy of their respective plant communities. 

Zehr, J., and Oremland, R. S. (1987). Reduction of selenate to selenide by sulfate-respiring bacteria experiments with cell suspensions and estuarine sediments. Appl. Environ. Microbiol. 53, 1365-1369. 

Oyaizu, H. and Woese, C.R. (1985) Phylogenetic-relationships among the sulfate respiring bacteria, myxobac-teria and purple bacteria. Syst. Appl Microbiol, 6 (3), 257—263. 

As a result, the partial breakdown of the organic matter by fermentation yields organic products with a low molecular weight, e.g., VFAs, along with C02. Compared with the aerobic respiration, the fermentation is inefficient however, these fermentation products can to some extent, and in addition to fermentable substrate, be used by the sulfate-reducing bacteria that make use of sulfate as the terminal electron acceptor (Nielsen and Hvitved-Jacobsen, 1988). In the absence of sulfate, the methanogenic bacteria utilize the low molecular... 

DUling W, Cypionka H. 1990. Aerobic respiration in sulfate-reducing bacteria. FEMS Microbiol Lett 71 123-8. 

The term sulfate-reducing bacteria (SRB) is frequently used to describe organisms which metabolize organic sulfates in fuel. Upon metabolism, the oxygen bound to the sulfate sulfur is consumed by the SRB and utilized in cellular respiration. The sulfur is reduced to H2S gas. Once liberated, H2S can react with fuel olefins to form mercaptans, contribute to microbial-induced corrosion, or escape into the fuel. 

Sulfate-reducing bacteria can engage in interspecies H2 transfer, in which H2 equivalents are transferred to other bacteria in lieu of SO respiration. For example ... 

Little is known about elemental sulfur reductase of the sulfur respiration system, though cytochrome c3 of the sulfate-reducing bacteria has been reported to reduce... 

Anoxic water samples, because they contain little in the way of particles, are far easier than aquifer materials to develop radioassays for the measurement of arsenate reduction. Arsenic speciation quantitatively changes from arsenate to arsenite with vertical transition from the surface oxic waters to the anoxic bottom depths of stratified lakes and fjords (55,56). This also occurs in Mono Lake, California (57), a transiently meromictic, alkaline (pH = 9.8), and hypersaline (salinity = 70-90 g/L) soda lake located in eastern California (Fig. 11). The combined effects of hydrothermal sources coupled with evaporative concentration have resulted in exceptionally high ( 200 fiM) dissolved arsenate concentrations in its surface waters. Haloalkaliphilic arsenate-respiring bacteria have been isolated from the lake sediments (26), and sulfate reduction, achieved with... 

Species of bacteria and Archaea get energy firom the back reaction [39,40]. These extant species use a variety of ferric iron sources including crystalline hematite. Their genes to do this may predate those for sulfate respiration. A vigorous ancient biospheric cycle based on Reaction (3) thus seems likely. Such photosynthesis could produce banded iron formations on the Earth [38] and hematite deposits on Mars [41] (see Ref. [42] for discussion of these rocks). The biosphere was upside-down from the modem one [43]. The ferric iron was immobile and built up if it is in a different place than the buried organic matter. One would not expect to find organic matter with ferrous iron formation as biota would have quickly consumed it by reacting it with an excess of hematite. 

Dasuffurlcants anaerobic bacteria of the genera Desulfovibrio and Desulfotomaculum whose Sulfate respiration (see) contributes to the process of Desulfurication (see). The most important of these bacteria is Desulfovibrio desulfuricans. Desulfovibrio are... 

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