Lysostaphin

Lysostaphin, an endopeptidase specific for the cell wall peptidoglycan of staphylococcus, is an extremely potent antistaphylococcal agent. Its molecular weight is 27kDa and is comprised of 246 amino acids. The isoeletric point of it is 10.5-11.0. The key enzymatic reaction of lysostaphin is the specific cleavage of the Gly-Gly bond in the pentaglycine subunit of the cell wall peptidoglycan and lyses cells in all metabolic states. Lysostaphin also hydrolyzes glycine-rich proteins such as insoluble elastin. .Both activities have a pH optimum in the neutral range and are inhibited by agent that would chelate the endogenous zinc, suggesting that zinc interferes directly with the catalytic activity of the enzyme. Lysostaphin has been in animals and topically in man against certain infections. It is used as a research and diagnostic tool. Because it lyses staphylococcus efficiently, it is widely used when preparing staphylococcal DNA or other cellular components for genetic and biochemical studies and for the preparation of protoplasts for transformation. Preparation and analysis of bacterial DNA has become a powerful tool used by clinical and other microbiologists in studies aimed at tracing source of infection or bacterial contamination.