title: Antimicrobial activities of LL-37 and its truncated variants against Burkholderia thailandensis.
abstract: Antimicrobial peptides (AMPs) are essential host defence molecules found in a wide variety of species and are promising antibacterial therapeutic candidates. Focusing on the human cathelicidin peptide LL-37, the aim of the present study was to explore the mechanisms of action and antimicrobial activities of a library of LL-37 fragments using Burkholderia thailandensis E264 as a model. The results revealed that IG-19 was the shortest fragment within LL-37 that exhibited antibacterial activity. LL-31, missing six residues at the C-terminus of LL-37, exhibited the strongest killing effect. Freeze-fracture electron microscopy of bacterial cells treated with either LL-37 or LL-31 revealed irregular bacterial surfaces with bleb projections, indicating that these peptides disrupted the integrity of the membrane. In addition, these peptides induced leakage of cell components, including nucleotides and even proteins. Altogether, the results obtained indicate the potential of using LL-31 as a new AMP to combat Burkholderia spp.
authors.affiliation: Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Sakawarat
authors.initials: S
authors.lastname: Kanthawong
authors.forename: Jan G M
authors.initials: JG
authors.lastname: Bolscher
authors.forename: Enno C I
authors.initials: EC
authors.lastname: Veerman
authors.forename: Jan
authors.initials: J
authors.lastname: van Marle
authors.forename: Kamran
authors.initials: K
authors.lastname: Nazmi
authors.forename: Surasakdi
authors.initials: S
authors.lastname: Wongratanacheewin
authors.forename: Suwimol
authors.initials: S
authors.lastname: Taweechaisupapong
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000235:genetics / Q000494:pharmacology*; D019117:Burkholderia / Q000187:drug effects* / Q000648:ultrastructure; D002462:Cell Membrane / Q000187:drug effects / Q000648:ultrastructure; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D046529:Microscopy, Electron, Transmission; D050505:Mutant Proteins / Q000494:pharmacology*; D017384:Sequence Deletion; D013329:Structure-Activity Relationship; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D050505:Mutant Proteins; D054804:Cathelicidins