Physiology of the thiobacilli: elucidating the sulphur oxidation pathway

Bacteria of the genus Thiobacillus can obtain energy from the chemolithotrophic oxidation of inorganic sulphur and its compounds (sulphide, thiosulphate and polythionates) and use this energy to support autotrophic growth on carbon dioxide. Despite many decades of work on them, the precise details of the pathway(s) for sulphur oxidation are still obscure. In this article the latest state of knowledge is analysed and a likely mechanism developed that takes account of all the experimental data available.