ANTIBACTERIAL ACTIVITY OF PEPTIDES HOMOLOGOUS TO A LOOP REGION IN HUMAN LACTOFERRIN

Human lactoferrin contains a 46 residue sequence named lactoferricin H thought to be responsible for its antimicrobial properties, Synthetic peptides HLT1, corresponding to the loop region of human lactoferrici n (FQWQRNMRKVRGPPVS) and HLT2, corresponding to its charged portion (F QWQRNMRKVR), exerted significant antibacterial effects against E, coli serotype O111 strains NCTC 8007 and ML35, The corresponding sequences in native human lactoferrin were shown to adopt a charged helix and h ydrophobic tail within the N-lobe remote from the iron binding site, S equence similarities between lactoferricin and dermaseptin and magaini ns suggest that lactoferricin may act as an amphipathic alpha helix.