Mupirocin also known as Pseudomonic acid A, Mupirocin is a potent antibiotic against both Gram (+) bacteria (Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Klebsiella pneumo niae) and some Gram (-) bacteria (Haemophilus influenzae, Neisseria gonorrhoeae)

The mode of action is believed to involve the inhibition of isoleucine-tRNA synthase enzyme that affects the peptide synthesis in bacteria.