DesVII is the glycosyltransferase responsible for the attachment of dTDP-D-desosamine to 10-deoxymethynolide or narbonolide during the biosynthesis of methymycin, neomethymycin, narbomycin, and pikromycin in the bacterium Streptomyces venezuelae. Activity requires an additional protein partner, DesVIII.