Inhibition of actinomycin synthesis by D-valine.

Abstract

THE actinomycins (I to V)1 synthesized by Streptomyces antibioticus each possess two moles of D-valine per mole of antibiotic2; Streptomyces chrysomallus, on the other hand, forms a mixture consisting of actinomycins IV (contains 2 moles D-valine), VI (contains l mole D-valine and l mole D-alloisoleucine) and VII (contains 2 moles D-alloisoleucine)2. During an investigation concerned with the mechanism of synthesis of D-amino acids by S. antibioticus, it was observed that the addition of D-valine to a chemically-defined medium3 in which the organism was growing resulted in a marked inhibition of actinomycin synthesis (Table 1, Fig. 1). The relationship of this event to that seen in penicillin biosynthesis with D-valine4,5 prompted a further investigation of this phenomenon.