Regulation by aromatic amino acids of the biosynthesis of candicidin by Streptomyces griseus.
The biosynthesis by Streptomyces griseus of candicidin, an aromatic polyene macrolide antibiotic, was inhibited by L-tryptophan, L-phenylalanine and, to a lesser degree, by L-tyrosine. A mixture of the three aromatic amino acids inhibited candicidin biosynthesis to a greater extent than did each amino acid separately. L-Tryptophan strongly inhibited the incorporation of the labelled precursors propionate or 4-aminobenzoic acid into candicidin. Incorporation of propionate into candicidin was 50% inhibited by 2.5 mM-tryptophan. Inhibition by tryptophan did not require protein synthesis as the same effect was observed in cells in which protein synthesis was prevented by chloramphenicol. The inhibitory effect of L-tryptophan was partially reversed by exogenous 4-aminobenzoic acid suggesting that this effect is exerted at the level of 4-aminobenzoic acid synthase.
D000935:Antifungal Agents / Q000096:biosynthesis*; D002174:Candicidin / Q000096:biosynthesis*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors; D010649:Phenylalanine / Q000494:pharmacology; D013305:Streptomyces griseus / Q000378:metabolism*; D013997:Time Factors; D014364:Tryptophan / Q000494:pharmacology; D014443:Tyrosine / Q000494:pharmacology
D000935:Antifungal Agents; D004791:Enzyme Inhibitors; D002174:Candicidin; D014443:Tyrosine; D010649:Phenylalanine; D014364:Tryptophan