title: Antimicrobial peptides with potential for biofilm eradication: synthesis and structure activity relationship studies of battacin peptides.
abstract: We report on the first chemical syntheses and structure-activity analyses of the cyclic lipopeptide battacin which revealed that conjugation of a shorter fatty acid, 4-methyl-hexanoic acid, and linearization of the peptide sequence improves antibacterial activity and reduces hemolysis of mouse blood cells. This surprising finding of higher potency in linear lipopeptides than their cyclic counterparts is economically beneficial. This novel lipopeptide was membrane lytic and exhibited antibiofilm activity against Pseudomonas aeruginosa, Staphylococcus aureus, and, for the first time, Pseudomonas syringe pv. actinidiae. The peptide was unstructured in aqueous buffer and dimyristoylphosphatidylcholine-polymerized diacetylene vesicles, with 12% helicity induced in 50% v/v of trifluoroethanol. Our results indicate that a well-defined secondary structure is not essential for the observed antibacterial activity of this novel lipopeptide. A truncated pentapeptide conjugated to 4-methyl hexanoic acid, having similar potency against Gram negative and Gram positive pathogens was identified through alanine scanning.
authors.affiliation: School of Chemical Sciences, The University of Auckland , Private Bag, 92019 Auckland, New Zealand.
authors.forename: Gayan Heruka
authors.initials: GH
authors.lastname: De Zoysa
authors.forename: Alan James
authors.initials: AJ
authors.lastname: Cameron
authors.forename: Veena V
authors.initials: VV
authors.lastname: Hegde
authors.forename: Srinivasarao
authors.initials: S
authors.lastname: Raghothama
authors.forename: Vijayalekshmi
authors.initials: V
authors.lastname: Sarojini
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D002463:Cell Membrane Permeability / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D055666:Lipopeptides / Q000138:chemical synthesis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008826:Microbial Sensitivity Tests; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D055666:Lipopeptides; C013629:octapeptin antibiotics