Oxidation of elemental sulfur by Thiobacillus ferrooxidans

In batch cultures of Thiobacillus ferrooxidans, the initial linear phase of sulfur oxidation was followed by the exponential one. It was shown that both free cells and cells adsorbed to the substrate were involved in the oxidation. Initially, only cells adsorbed to the substrate consumed oxygen. During the exponential phase, they accounted for only half the oxygen consumed; the other half was consumed by free cells. After the cells adsorbed to the substrate were removed, the oxygen consumption by free cells decreased significantly.