The Biosynthesis of Chloramphenicol. III. Effects of Micronutrients on Synthesis

SUMMARYThe effects of the microelements Zn, Fe, Mn, Mo, Co, Cu, B, and Ga and the macroelement, Mg, on growth and chloramphenicol production by Streptomyces venezuelane were studied. Elimination of Zn or Fe from the microelement mixture added to a CaCO3-treated synthetic medium resulted in the absence of chloramphenicol production. No one mineral in the synthetic medium would support antibiotic production, but the addition of Zn with Fe resulted in good production. Mg at levels of 5 × and 10 × 10-5 M was best for chloramphenicol production; levels of 7.5 × and 10 × 10-2 M were optimum for growth. Mn could replace Mg in the growth requirement, but only an Mn concentration of 10-2 M allowed any chloramphenicol production. Presence or absence of the other microelements studied, singly or in groups, had little effect on growth or production in the medium containing optimum concentrations of Zn, Fe, and Mg.