About mupirocina naturally antibiotic isolated from pseudomonas fluorescens, antibiotic.ssmechanism of action of mupirocinsmupirocin exerts its action by reversibly binding to isoleucyl transfer rna synthetase and inhibits the enzyme activity. this enzyme is necessary for the synthesis of proteins in the bacteria. inhibition of isoleucyl transfer rna synthetase results in inhibition of protein synthesis and produce microbicidal action. it is more active against gram positive bacteria as compared to gram negative bacteria.ssindications for mupirocinsbacterial skin infections: s1. impetigo s2. infected eczema s3. folliculitis s4. eradication of nasal colonization of methicillin resistant s.aureus s