Erythromycin thiocyanate is a macrolide antibiotic produced by the actinomycete Streptomyces erythreus with a broad spectrum of antimicrobial activity.Erythromycin thiocyanate acts by binding to the 50S ribosomal subunit of the bacterium and inhibits RNA-dependent protein synthesis without affecting nucleic acid synthesis, through the blockade of transpeptidation and/or translocation reactions. Erythromycin thiocyanate acts by binding to the 50S ribosomal subunit of bacteria and inhibits RNA-dependent protein synthesis by blocking transpeptide and/or translocation reactions without affecting nucleic acid synthesis.