A novel antifungal analog peptide derived from protaetiamycine.
Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner. As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active mechanism of 9Pbw4 could have originated from the poreforming action and the radii of pores was presumed to be anywhere from 1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential of 9Pbw4 as a novel antifungal peptide.
School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu 702-701, Korea.
Juneyoung
J
Lee
Hyun Joo
HJ
Hong
Jin-Kyoung
JK
Kim
Jae-Sam
JS
Hwang
Yangmee
Y
Kim
Dong Gun
DG
Lee
D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D002176:Candida albicans / Q000166:cytology / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D023082:Defensins / Q000737:chemistry*; D003911:Dextrans / Q000378:metabolism; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry / Q000494:pharmacology*; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*
C548157:9Pbw2 peptide; C548158:9Pbw4 peptide; D000935:Antifungal Agents; D023082:Defensins; D003911:Dextrans; D019476:Insect Proteins; D009842:Oligopeptides; D010455:Peptides; C015219:fluorescein isothiocyanate dextran; C548156:protaetiamycine protein, Protaetia brevitarsis; D016650:Fluorescein-5-isothiocyanate