The mode of action of berninamycin and mechanism of resistance in the producing organism, Streptomyces bernensis.

The mode of action of berninamycin on bacterial protein synthesis is related to that of thiostrepton, a dissimilar compound. Both antibiotics bind to the complex of 23S RNA with protein L11 and both affect various functions of the ribosomal A site. Also, Streptomyces bernensis and Streptomyces azureus (which, respectively, produce berninamycin and thiostrepton) possess similar ribosomal RNA methylases capable of rendering ribosomes resistant to these compounds. Resistance involves specific pentose-methylation of 23S ribosomal RNA.