Antimicrobial peptides (AMP) inactivate microorganisms by forming pores in cell membrane. Pore formation in DMPC bilayers by AMP melittin, its mutants G1I (higher hydrophobicity) and I17K (higher net charge) and Cecropin P1 as monitored by leakage of fluorescent dye calcein, encapsulated within DMPC liposomes indicated that the leakage rates and extent  of leakage were in the order Cecropin P1 &gt; melittin &gt; G1I &gt; I17K. A mathematical model for the evaluation of energy barrier for formation of pore consisting of peptide aggregates of different size interspersed with phospholipid head was proposed which considers detailed pore structure as well as intermolecular interactions. Estimated free energy barrier for insertion of melittin into an ideal paraboloid pore were compared with those evaluated by potential mean  force  calculations. The model was employed to elucidate the rates of formation and dissociation of pores by AMP and nucleation of pores in lipid bilayers.<br/>

Pore formation by aggregates of antimicrobial peptides in DMPC liposomes

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.