Immobilized Lipid Affinity Capture for Antimicrobial Peptides Screening

A novel method for rapid screening of antimicrobial peptides (AMPs) was developed by using immobilized lipid affinity capture (ILAC) coupled with LC-MS. Phospholipid (PL) mixture containing phosphatidyl glycerol (PG): phosphatidyl ethanolamine (PE) (4:1), roughly mimic the PL composition of Gram-positive bacterial membrane, was covalently immobilized on magnetic particles (MPs). PL monolayer immobilized on MPs was used as a matrix for capturing of the membrane-disruptive AMPs. Hominicin, a new AMP against Gram-positive bacteria, was successfully captured by ILAC from the peptide pool of Staphylococcus hominis MBBL 2–9. The hominicin was identified by the comparative analysis of LC-MS 2Dprofiles of peptides captured by bare and PL-immobilized MPs. This is the first report for the development of rapid AMP screening method using lipid-immobilized MPs and LC-MS which will be a promising tool for discovery of various kinds of AMPs.