ZINC STIMULATION OF RNA AND PROTEIN SYNTHESIS IN RHIZOPUS NIGRICANS.

Addition of 1.7 x 10-(5)M zinc sulfate to cultures of Rhizopus nigricans increases growth and substrate utilization. Analysis of cells during the course of growth, after addition of the metal, showed that there was an immediate increase in RNA, followed by a corresponding increase in protein and cell mass. The DNA content was affected to a lesser extent. It is postulated that Zn(++) stimulates growth through a primary effect on RNA synthesis.