Viomycin (VM)

Viomycin is a member of the tuberactinomycin family,a group of nonribosomal peptide antibiotics exhibiting anti-tuberculosis properties. The tuberactinomycin family is an essential component in the drug cocktail currently used to fight infections of Mycobacterium tuberculosis. Viomycin was the first member of the tuberactinomycins to be isolated and identified and was used to treat TB until it was replaced by the less toxic, but structurally related compound, capreomycin. The tuberactinomycins target bacterial ribosomes, binding RNA and disrupting bacterial protein biosynthesis. It is produced by the actinomycete Streptomyces puniceus, that binds to RNA and inhibits prokaryotic protein synthesis and certain forms of RNA splicing. The gene cluster for viomycin has been sequenced from Streptomyces sp. The NRPS contains 4 proteins: VioA, VioF, VioI, and VioG.