title: Purification and characterization of an antimicrobial histone H1-like protein and its gene from the testes of olive flounder, Paralichthys olivaceus.
abstract: An approximately 21 kDa antimicrobial protein was purified from an acidified testis extract of olive flounder, Paralichthys olivaceus, by ion-exchange and C(18) reversed-phase HPLC. A comparison of the N-terminal amino acid sequence with those of other known antimicrobial polypeptides revealed high homology between this antimicrobial protein and other histone H1 molecules; thus, it was designated flounder histone H1-like protein (fH1LP). fH1LP showed potent antimicrobial activity against Gram-positive bacteria, including Bacillus subtilis, Staphylococcus aureus, and Streptococcus iniae (minimal effective concentrations [MECs], 2.8-30.0 μg/ml), Gram-negative bacteria, including Aeromonas hydrophila, Escherichia coli D31, Vibrio parahaemolyticus (MECs, 1.4-12.0 μg/ml), and Candida albicans (MEC, 2.0 μg/ml). cDNA cloning and tissue distribution studies of fH1LP indicated that it is constitutively expressed in testis and ovary. The fH1LP expression level was significantly dependent on developmental stage, and decreased dramatically after hatching. However, lipopolysaccharide stimulation did not induce fH1LP mRNA in other immune organs, including the kidney and spleen. These results suggest that fH1LP plays an important role in innate immunity in fish during reproduction, including mating, fertilization, and hatching.
authors.affiliation: Biotechnology Research Division, National Fisheries Research and Development Institute, 408-1 Sirang-ri, Gijang-eup, Gijang-Gun, Busan 619-902, Republic of Korea. bhnam@nfrdi.go.kr
authors.forename: Bo-Hye
authors.initials: BH
authors.lastname: Nam
authors.forename: Jung-Kil
authors.initials: JK
authors.lastname: Seo
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Go
authors.forename: Min Jeong
authors.initials: MJ
authors.lastname: Lee
authors.forename: Young-Ok
authors.initials: YO
authors.lastname: Kim
authors.forename: Dong-Gyun
authors.initials: DG
authors.lastname: Kim
authors.forename: Sang-Jun
authors.initials: SJ
authors.lastname: Lee
authors.forename: Nam Gyu
authors.initials: NG
authors.lastname: Park
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D018076:DNA, Complementary / Q000737:chemistry; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D005432:Flounder / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D006657:Histones / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013737:Testis / Q000378:metabolism
chemical_list: D000276:Adjuvants, Immunologic; D000890:Anti-Infective Agents; D018076:DNA, Complementary; D029941:Fish Proteins; D006657:Histones; D008070:Lipopolysaccharides