Biosynthesis of the spermidine and guanidino units in the glycocinnamoylspermidine antibiotic cinodine.

Abstract

The biosynthesis of the spermidine and guanidino groups was studied with 14C- and 13C labeled intermediates. Arg, citrulline and ornithine were incorporated in good efficiency. The guanidino group of arginine and the ureido group of citrulline both labeled the guanidino group on the hexose sugar. None of the ureido groups in the antibiotic was enriched. Citrulline was apparently converted to Arg before use in the biosynthesis. Arg, citrulline and ornithine were incorporated as the 4-carbon unit of spermidine. All of the labeled 5 carbon from ornithine or from citrulline appeared adjacent to the secondary amine in the 4-carbon unit of spermidine. Onbound putrescine was evidently not an immediate precursor of spermidine. [Nocardia cultures were used.].