Thiobacillus denitrificans

More specifically, the invention involves the use of Thiobacillus denitrificans under anaerobic conditions to oxidize sulfur compounds such as hydrogen sulfide to sulfate. The process may be carried out in various ways such as in a batch or a continuous bioreactor system using a suspended or an immobilized biocatalyst. The method is particularly applicable to treating natural gas containing hydrogen sulfide and producing a biomass byproduct. 

The best example for facultative anaerobic autotrophic respiration is represented by Thiobacillus denitrificans, as shown in the denitrification reaction g ... 

It now seems probable that cleavage of thiosulfate in T. thioparus (and Thiobacillus denitrificans) depends not on a reductase as originally perceived by Peck (1960) but on a sulfur transferase of the rhodanese type (Peck 1968). Rhodanese is usually detected by its ability to transfer the sulfane-sulfur of thiosulfate to the nonphysiologic acceptor cyanide, producing thiocyanate and liberating sulfite ... 

Bowen TJ, Happold FC, Taylor BE 1966. Studies on adenosine 5 -phosphosntfate reductase from Thiobacillus denitrificans. Biochim Biophys Acta 111 566-76. 

Kelly DP, Wood AP. 2000b. Confirmation of Thiobacillus denitrificans as a species of the genus Thiobacillus, in the P-subclass of the Proteobacteria, with strain NCIMB 9548 as the type strain. Int J Syst Evol Microbiol 50 547-50. 

Taylor BE 1989. Thermotolerance of adenylylsulfate reductase from Thiobacillus denitrificans. FEMS Microbiol Lett 59 351. ... 

Timmer-ten Hoor, A. 1981. Cell yield and bioenergetics of Thiomicrospira denitrificans compared with Thiobacillus denitrificans. Antonie Leeuwenhoek 47 231 3. 

LeGall, J., Payne, W. J., Morgan, T. V., and DerVartanian, D. (1979). On the purification of nitrite reductase from Thiobacillus denitrificans and its reaction with nitrite under reducing conditions. Biochem. Biophys. Res. Commun. 87, 355-362. 

By contrast, under anaerobic conditions, the reverse reaction becomes spontaneous and organisms such as Micrococcus denitrificans and Thiobacillus denitrificans can reduce nitrate as an energy source. 

Schedel, M., and Truper, H. (1980) Anaerobic oxidation of thiosulfate and elemental sulfur in Thiobacillus denitrificans. Arch. Microbiol. 124, 205-210. 

Denitrifying nitrate reducers such as Paracoccus denitrificans, Thiobacillus denitrificans, and various pseudomonads follow a more complete reduction pathway, converting nitrate through nitrite to nitric oxide, nitrous oxide and lastly to molecular nitrogen ... 

Thiobacillus denitrificans, however, can utilize nitrate ions as terminal electron acceptors in the oxidation of inorganic sulfur compounds ... 

Solubilization, uptake, and precipitation of Ca and Si are directly (or at least energetically) linked to the photosynthetic and respiratory cycling of C, H, and O. Acids from nitrification and sulfur oxidation aid phosphorus mobilization photosynthesis or respiration is required for the uptake and conversion of phosphorous into high-energy phosphate. Sulfur is oxidized (with the concomitant reduction of nitrate) by Thiobacillus denitrificans, likewise, some extremely thermophilic methanogens can transfer hydrogen not only to CO2, but also to S. These are a few examples of interrelations involved in biogeochemical cycles. 

Dalsgaard T. and Bak F. (1992) Effect of acetylene on nitrous oxide reduction and sulfide oxidation in batch and gradient cultures of Thiobacillus denitrificans. Appl. Environ. Microbiol. 58, 1601-1608. 

The use of Thiobacillus species has been studied quite extensively. Sublette and Sylvester especially focused on the use of Thiobacillus denitrificans [50-52] for aerobic or anaerobic oxidation of sulfide to sulfate. In the anaerobic oxidation NOs was used as an oxidant instead of oxygen (confirm Table 2). Buisman used a mixed culture of Thiobacilli for the aerobic oxidation of sulfide to elemental sulfur and studied technological applications [53-55]. Visser showed the dominant organism in this mixed culture to be a new organism named Thiobacillus sp. W5 [6]. 

Fig. 1.9. A schematic presentation of the mechanisms by which Thiobacillus denitrificans acquires energy and biosynthesizes organic compounds...

Thiobacillus denitrificans is well known as a lithoautotrophic denitrifier it oxidizes anaerobically thiosulfate (S2032 ) with nitrate (N03 ) to biosynthesize ATP although it also aerobically oxidizes thiosulfate (Aminuddin and Nicholas, 1973, 1974a) (Fig. 1.9). The anaerobic oxidation system of thiosulfate is similar to those of other thiobacilli (though these are aerobic bacteria), and the denitrifying processes in the bacterium are similar to those in the heterotrophic denitrifiers. The complete genome of the bacterium has recently been sequenced (Beller et al., 2006). 

Adams CA, Warnes GM, Nicholas DJD (1971) A sulphite-dependent nitrate reductase from Thiobacillus denitrificans. Biochim Biophys Acta 234 398-406... 

Aminuddin M (1980) Substrate level versus oxidative phosphorylation in the generation of ATP in Thiobacillus denitrificans. Arch Microbiol 128 19-25... 

Aminuddin M, Nicholas DJD (1973) Sulphide oxidation linked to the reduction of nitrate and nitrite in Thiobacillus denitrificans. Biochim Biophys Acta 325 81-93... 

S042-, so S accumulates. This S can be oxidized to S042- by Thiobacillus denitrificans, a chemosynthet-ic bacterium that is unusual for Thiobacillus species in being a facultative anaerobe (a nitrate reducer). The S can also be reduced to S2 for example, by Desuifuromonas acetoxidans, which lives in syn-trophic association with Chlorobium (Kuenen et al. 1985). 

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