Desulfo vibrio

Lloyd JR, J Ridley, T Khizniak, NN Lyalikova, LE Macaskie (1999) Reduction of technetium by Desulfo-vibrio desulfuricans biocatalyst characterization and use in a flowthrough bioreactor. Appl Environ Microbiol 65 2691-2696. 

Figure 16-31 (A) Structure of molybdopterin cytosine dinucleotide complexed with an atom of molybdenum. (B) Stereoscopic ribbon drawing of the structure of one subunit of the xanthine oxidase-related aldehyde oxidoreductase from Desulfo-vibrio gigas. Each 907-residue subunit of the homodimeric protein contains two Fe2S2 clusters visible at the top and the molybdenum-molybdopterin coenzyme buried in the center. (C) Alpha-carbon plot of portions of the protein surrounding the molybdenum-molybdopterin cytosine dinucleotide and (at the top) the two plant-ferredoxin-like Fe2S2 clusters. Each of these is held by a separate structural domain of the protein. Two additional domains bind the molybdopterin coenzyme and there is also an intermediate connecting domain. In xanthine oxidase the latter presumably has the FAD binding site which is lacking in the D. gigas enzyme. From Romao et al.633 Courtesy of R. Huber.

A few obligate anaerobes obtain energy by using sulfate ion as an oxidant.355-3563 For example, Desulfo-vibrio desulfuricans catalyzes a rapid oxidation of H2 with reduction of sulfate to H2S (Eq. 18-31). 

Figure 6. Flavin binding site of the flavodoxin isolated from Desulfo-vibrio vulgaris [36].

Sulphate reduction becomes important when nitrate is depleted its products are carbon dioxide, water and hydrogen sulphide (Box 3.10). Sulphate reducers (e.g. Desulfo vibrio, Desuifolomaculum, Desulfobacter,... 

Kaplan IR, Rittenberg SC (1964) Carbon isotope fractionation during metabolism of lactate by Desulfo-vibrio desulfuricans. J Gen Microbiol 34 213-217... 

Sulfate reduction reduction of the sulfote ion S04 " to the sulfide ion S, in which the hexavalent, positive sulfur of the sulfate is converted to the divalent, negative form. S.r. must be preceded by Sulfate activation (see). The substrate of enzymatic S.r. is therefore either adenosine phosphosulfate (APS) or phosphoadenosinephosphosulfate (PAPS). The enzy-mology of S.r. has been studied in particular in enzyme preparations from baker s yeast (Saccharomy-ces cerevisiae) and the anaerobic bacterium Desulfo-vibrio desulfuricans. The former organism performs assimilatory S.r. (see Sulfate assimilation), Ae latter dissimilatory S.r. (see Sulfate respiration). 

Dubourdieu M, le Gall J, Favaudon V (1975) Physicochemical properties of flavodoxin from Desulfo-vibrio vulgaris. Biochim Biophys Acta 376 519-532... 

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