Isoleucine added to the cultivation medium of Streptomyces cinnamonensis C-100-5 induced a relative increase of the production of monensin B at the expense of monensin A. U-14C-Isoleucine was found not to be a specific monensin B precursor. The incorporation of 1-13C-2-methylbutyrate into monensins A and B showed the label to be evenly incorporated in both products at carbon atoms originating from C(1) of propionate. In regulatory mutants insensitive to 2-amino-3-chlorobutyrate isoleucine influenced the production of monensins only slightly but strains resistant to 2-aminobutyrate and norleucine decreased their total production by 2-12% in the presence of isoleucine which was associated with a decrease of monensin A content by 14-52%. The inhibitory effect of isoleucine on the biosynthesis of valine, a specific precursor of the butyrate unit of monensin A, is discussed.

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J Mol Biol. 1970 May 14;49(3):533-46 PubMed

Antimicrob Agents Chemother. 1973 Oct;4(4):410-4 PubMed

Folia Microbiol (Praha). 1982;27(4):275-7 PubMed

J Am Chem Soc. 1967 Oct 25;89(22):5737-9 PubMed

J Antibiot (Tokyo). 1983 May;36(5):617-9 PubMed

Antimicrob Agents Chemother (Bethesda). 1967;7:349-52 PubMed

Antimicrob Agents Chemother (Bethesda). 1967;7:359-62 PubMed

Ann N Y Acad Sci. 1954 Oct 29;60(1):136-51 PubMed

Annu Rev Biochem. 1978;47:532-606 PubMed

Folia Microbiol (Praha). 1985;30(1):30-3 PubMed

Helv Chim Acta. 1971;54(4):1103-8 PubMed

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Propionate and the production of monensins in Streptomyces cinnamonensis