ENZYMATIC-SYNTHESIS OF AMINOCYCLITOL MOIETIES OF AMINOGLYCOSIDE ANTIBIOTICS FROM INOSITOL BY STREPTOMYCES SPP - DETECTION OF GLUTAMINE-AMINOCYCLITOL AMINOTRANSFERASE AND DIAMINOCYCLITOL AMINOTRANSFERASE ACTIVITIES IN A SPECTINOMYCIN PRODUCER

Extracts of stationary-phase mycelia of the spectinomycin producer Str eptomyces flavopersicus ATCC 19756 catalyzed inositol dehydrogenase, L -glutamine:inosose aminotransferase, 2-epi-streptamine:inosose aminotr ansferase, streptamine:inosose aminotransferase, N-3-methyl-2-deoxystr eptamine:inosose aminotransferase, and aminodeoxy-scyllo-inositol:inos ose aminotransferase reactions, as detected with a new rapid assay pro cedure. These results suggest that one or both amino groups of the N-1 , N-3-dimethyl-2-epi-streptamine moiety of spectinomycin are derived b y transamination from the alpha-amino group of L-glutamine, An enzymat ic procedure for distinguishing among N-1- and N-3-monomethyl diaminoc yclitol derivatives and their diaminocyclitol biosynthetic precursors is described, A scheme showing key roles of glutamine-aminocyclitol am inotransferases in biosynthesis of major aminoglycoside antibiotics is presented.