OXYJAT-300 LA is a broad spectrum antibiotic isolated from the fungus Streptomyces rimosus. It inhibits protein synthesis by binding reversibly to receptors on 30S ribosomal subunit of susceptible microorganisms. The binding of a tetracycline to the subunit blocks the binding of the aminoacyl tRNA to the acceptor site on the mRNA -ribosomal complex and prevents the addition of new amino acids to the peptide chain, inhibiting protein synthesis.