Biological conversion of narbonolide to picromycin.

New olivosyl derivatives of methymycin/pikromycin from an engineered strain of Streptomyces venezuelae.

A mutant strain of Streptomyces venezuelae was engineered by deletion of the entire gene cluster related to biosynthesis of the endogenous deoxysugar (TDP-D-desosamine) and replacement with genes required for biosynthesis of an intermediate sugar (TDP-4-keto-6-deoxy-D-glucose) or an exogenous sugar (TDP-D-olivose), from the oleandomycin and urdamycin deoxysugar pathways. The 'sugar-flexible' gl...

A gene cluster for macrolide antibiotic biosynthesis in Streptomyces venezuelae: architecture of metabolic diversity.

In a survey of microbial systems capable of generating unusual metabolite structural variability, Streptomyces venezuelae ATCC 15439 is notable in its ability to produce two distinct groups of macrolide antibiotics. Methymycin and neomethymycin are derived from the 12-membered ring macrolactone 10-deoxymethynolide, whereas narbomycin and pikromycin are derived from the 14-membered ring macrolac...

Chain elongation, macrolactonization, and hydrolysis of natural and reduced hexaketide substrates by the picromycin/methymycin polyketide synthase.

The biosynthesis of picromycin using 13C enriched precursors.

Sir: Using 13C enriched precursors it has been elucidated recently1) that the aglycone of the leucomycins was derived from five acetates, one propionate, one butyrate and an unknown C2-unit corresponding to carbons-3 and -4. In the case of magnamycin which is C-9 oxidation product of leucomycin, previous studies using 14C labeled precursors2) suggested an acetate origin for carbons-3 and -4. An...

Synthesis of Macrolide Antibiotics. IV. Stereoselective Syntheses of the 3-0-Methyl and the 11-0-Methyl Derivatives of the C(1)-C(6) Segment of Erythrono1ides A and B and the C(9)-C(15) Segment of Erythronolide A, Respectively.tf

By appropriate dissection of the macrocyclic lactone ring of methymycin erythromycins A and B, picromycin and narbomycin, carbohydrate-like structural segments were obtained. The finding that the anomeric configuration of a glycopyranoside effectively controls the stereochemistry of various addition reactions to sp' (C=O and C=C) carbon atoms of a glycopranoside ring led to the development of a...