title: Purification and characterization of YFGAP, a GAPDH-related novel antimicrobial peptide, from the skin of yellowfin tuna, Thunnus albacares.
abstract: A 3.4 kDa of antimicrobial peptide was purified from an acidified skin extract of the yellowfin tuna, Thunnus albacares, by preparative acid-urea-polyacrylamide gel electrophoresis and C(18) reversed-phase HPLC. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high homology with the N-terminus of glyceraldehyde-3-phosphate dehydrogenase (GAPDH); thus, this peptide was designated as the yellowfin tuna GAPDH-related antimicrobial peptide (YFGAP). YFGAP showed potent antimicrobial activity against Gram-positive bacteria, such as Bacillus subtilis, Micrococcus luteus, and Streptococcus iniae (minimal effective concentrations [MECs], 1.2-17.0 μg/mL), and Gram-negative bacteria, such as Aeromonas hydrophila, Escherichia coli D31, and Vibrio parahaemolyticus (MECs, 3.1-12.0 μg/mL) without significant hemolytic activity. According to the secondary structural prediction and the homology modeling, this peptide forms an amphipathic structure and consists of three secondary structural motifs including one α-helix and two parallel β-strands. This peptide did not show membrane permeabilization ability and its activity was bacteriostatic rather than bactericidal. This is the first report of the isolation of an antimicrobial peptide from a tuna species and the first description of the antimicrobial function of the N-terminus of GAPDH of an animal species.
authors: Department of Biotechnology, Pukyong National University, Daeyeon Campus, Yongso-ro, Nam-Gu, Busan 608-737, Republic of Korea.
authors: Jung-Kil
authors: JK
authors: Seo
authors: Min Jeong
authors: MJ
authors: Lee
authors: Hye-Jin
authors: HJ
authors: Go
authors: Tae Hyun
authors: TH
authors: Park
authors: Nam Gyu
authors: NG
authors: Park
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000378:metabolism*; D001412:Bacillus subtilis / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry / Q000378:metabolism*; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000378:metabolism; D014413:Tuna / Q000378:metabolism*
chemical_list: D023181:Antimicrobial Cationic Peptides; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases