[Nature of the sulfur-containing component and its function in Thiobacillus ferrooxidans]

As was shown using various reagents (Ag+, Cd2+) and solvents (ethanol, methanol), Thiobacillus ferrooxidans cells accumulate colloidal sulfur when they grow in the medium 9K containing elemental sulfur. Colloidal sulfur is accumulated in the periplasmic space, in large, bipolarly arranged spherical structures and in simple invaginates of the cytoplasmic membrane. T. ferrooxidans cells accumulate the sulfur at a highest rate during the stationary phase of growth and can use it as a source of energy under the conditions of starvation. The factors causing sulfur accumulation in T. ferrooxidans cells are discussed.