Two Factors Affecting on Iron-oxidizing Activities of Thiobacillus ferrooxidans

Abstract

The solubilization method of the iron-oxidizing system of T. ferrooxidans was investigated. Two factors affected the iron-oxidizing and cytochrome-oxidizing activities of the bacterium, and they were separated by sonication in different ionic strengths of potassium phosphate buffer (pH 7.5). One of them stimulated both activities and was tentatively called the stimulating factor. The other inhibited both activities and was tentatively called the inhibiting factor. The stimulating factor was a light yellowish-green and heat labile substance. The inhibiting factor was a fairly heat stable and not dialyzable substance and masked the stimulating factor activity.