Sulfur compounds, oxidation, thiobacilli

Of great importance are the microorganisms metabolizing sulfur and/or sulfur compounds oxidatively and/or reductively. As an example, Thiobacilli particularly excrete sulfuric acid as a final product of their oxi-... 

Bacteria of the genus Thiobacillus, obtain energy not by oxidation of organic compounds, but by oxidation of inorganic sulfur compounds (including sulfides) to sulfuric acid. The following reactions are performed by mixed cultures of Thiobacilli... 

Although these equations held true for some strains of bacteria under some growth conditions, they did not help explain the commonly observed quantitative conversion of both sulfur atoms of thiosulfate to sulfate, rather than the liberation of the sulfane-sulfur mainly as elemental sulfur. During the 1960s, cyclic reactions of polythionates and other polysulfur compounds continued to be postulated as mechanisms for thiosulfate and polythionate metabolism (Trudinger 1967), but none of these was supported at the time by strong biochemical evidence. The time was opportune for a new approach to the problem of thiosulfate oxidation in thiobacilli. 

---