Bacteria sulfur-oxidising

Hydrogen sulfide can be oxidised to elemental sulfur, for example, by green and purple sulfur bacteria. Further oxidation of elemental sulfur by sulfur oxidising bacteria can produce sulfate. 

Microbial interactions among aerobic and anaerobic sulfur-oxidising bacteria. Adv. Microbial. Ecol. 8, 1—59. 

Sulfur-oxidising bacteria convert inorganic sulfur compounds to sulfuric acid that can cause severe damage to mineral material. Thiobacillus species have been implicated with concrete corrosion in the Melbourne and Hamburg sewer systems due to sulfuric acid formation. However, a role in stone decay is less certain since sulfuric acid and calcium sulfate in stone can originate from the direct action of atmospheric pollution and acid rain. 

Considerable damage is also caused to concrete and marble by sulfur oxidising bacteria capable of producing acids. 

W. Sand, E. Bock, D. C. White, Biotest system for rapid evaluation of concrete resistance to sulfur-oxidising bacteria . Materials Performance, 1987, 26, 14-17. 

SRB - Sulfate reducing bacteria. SOB - Sulfur oxidising bacteria. 

There is considerable evidence that, in nature, bacterial sulfate reduction plays an important role in the formation of some deposits of elemental sulfur. Free sulfur is not, however, produced by sulfate-reducers per se and its formation depends, therefore, on chemical or biological oxidation of sulfide. Microorganisms capable of effecting the latter reaction are discussed in Chapters 6.1 and 6.3 while isotopic selectivities associated with this conversion are summarised in Table 6.4.2 (see p. 406). As discussed in Chapters 6.1 and 6.3 colourless sulfide-oxidising bacteria, e.g. Beggiatoa, and Thio-bacillus, inhabit aerobic zones of ponds, etc. while in the underlying anaerobic zones, where light can penetrate, photosynthetic oxidisers, such as Chro-matium and Chlorobium, are active. 

The mining of massive sulfur deposits and the exposure of the element to air and water permits the development of populations of sulfur-oxidizing bacteria, with concomitant formation of acidity and sulfate ions. The occurrence of T. thiooxidans and T. thioparus in the Rozdol deposit in Russia has been described by Karavaiko (1959 1961). Similar events can occur during the industrial uss e of elemental sulfur and the amenability of sulfur to bacterial oxidation has been widely exploited agriculturally for modification of soil acidity, supply of sulfate ion and for in situ solubilisation of rock phosphate (Starkey, 1950 Gleen and Quastel, 1953 Vitolins and Swaby, 1969). While most attention has been focussed on chemolitho-trophic thiobacilli, such as T. thiooxidans and T. thioparus, an ability to oxidise elemental sulfur has been shown to be possessed by a number of heterotrophs such as the 35 species of Streptomyces examined by Yagi et al. (1971) and Arthrobacter (Ehrlich, 1962). 

Brock, T.D. and Gustafson, J., 1976. Ferric iron reduction by sulfur- and iron-oxidising bacteria. Appl. Environ. Microbiol., 32 567—571. 

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