Penetration of Milk-Derived Antimicrobial Peptides into Phospholipid Monolayers as Model Biomembranes

摘要: Three antimicrobial peptides derived from bovine milk proteins were examined with regard to penetration into insoluble monolayers formed 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) sodium salt (DPPG). Effects on surface pressure (Π) and electric potential (ΔV) measured, Π a platinum Wilhelmy plate ΔV vibrating plate. The measurements performed under stationary diffusion conditions upon the compression of monolayers. two type showed greatly different effects peptide-lipid interactions. Results show that peptide interactions DPPC monolayer are weak, repulsive, nonspecific while DPPG significant, attractive, specific. These results in accord fact disrupt bacteria membranes (negative) no significant effect host (neutral) is observed. No such discrimination was revealed isotherms. latter indicate squeezing penetrant out does not allow for establishing equilibrium, so remains supersaturated shows an under-equilibrium orientation within entire range, practically.