title: Characterization of Japanese flounder (Paralichthys olivaceus) NK-lysin, an antimicrobial peptide.
abstract: The NK-lysin cDNA of Japanese flounder, Paralichthys olivaceus, consists of 657bp, containing an open reading frame (ORF) of 444bp, which encodes 147 amino acid residues. The amino acid sequence of Japanese flounder NK-lysin has 21% identity to porcine NK-lysin and bovine NK-lysin, 23% to equine NK-lysin, and 46% to zebrafish NK-lysin-like protein. Multiple alignments of Japanese flounder NK-lysin and other known saposin-like proteins revealed that the six cysteine residues important for structural folding are completely conserved. The Japanese flounder NK-lysin gene is approximately 2kb and consists of five exons and four introns. Japanese flounder NK-lysin mRNA constitutive expression was mainly detected in gills, heart, head kidney, intestines, peripheral blood leukocytes (PBLs), spleen and trunk kidney, and was detected at low levels in liver, muscle and ovary. However, expression was not detected in brain, skin and stomach of apparently healthy Japanese flounder. Gene expression of Japanese flounder NK-lysin was not inducible by lipopolysaccharide (LPS) treatment. A synthesized NK-lysin peptide, consisting of 27 amino acid residues, showed antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Photobacterium damselae subsp. piscicida.
authors.affiliation: Laboratory of Genome Science, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-ku, Tokyo 108-8477, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Hirono
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Kondo
authors.forename: Takashi
authors.initials: T
authors.lastname: Koyama
authors.forename: Nur Rahmawaty
authors.initials: NR
authors.lastname: Arma
authors.forename: Jee Youn
authors.initials: JY
authors.lastname: Hwang
authors.forename: Reiko
authors.initials: R
authors.lastname: Nozaki
authors.forename: Naoko
authors.initials: N
authors.lastname: Midorikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Aoki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001419:Bacteria / Q000187:drug effects; D001483:Base Sequence; D016827:CD8 Antigens / Q000096:biosynthesis; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000737:chemistry; D005432:Flounder / Q000235:genetics / Q000502:physiology*; D015870:Gene Expression / Q000187:drug effects / Q000276:immunology*; D020869:Gene Expression Profiling / Q000662:veterinary; D008070:Lipopolysaccharides / Q000494:pharmacology; D008969:Molecular Sequence Data; D011510:Proteolipids / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D016415:Sequence Alignment
chemical_list: D016827:CD8 Antigens; D017931:DNA Primers; D018076:DNA, Complementary; D008070:Lipopolysaccharides; C093238:NK-lysin; D011510:Proteolipids