Actinomycete metabolism: origin of the guanidine groups in streptomycin

Abstract

Investigations carried out on Streptomyces griseus with the aid of C14O2 have shown that the carbons of the guanidine side chains in streptomycin are derived very largely, and possibly entirely, from CO2. The maximum incorporation of C14O2 into streptomycin obtained was between 0.4 and 0.5%. A much lower degree of fixation of C14 was obtained when no C14O2 was passed for the first 72 hours of a fermentation. L-Arginine possibly functions as an intermediate in the biosynthesis of the guanidine side chains of streptomycin. A variety of compounds, either containing guanidine groups or readily convertible into such compounds, are converted by S. griseus into a further substance containing at least one guanidine group. This compound has not yet been identified, but may be involved in the biosynthesis of streptomycin by the organism.