title: Isolation and identification of antimicrobial components from the epidermal mucus of Atlantic cod (Gadus morhua).
abstract: The epidermal mucus of fish species has been found to contain antimicrobial proteins and peptides, which is of interest in regard to fish immunity. An acidic extract from the epidermal mucus of the Atlantic cod (Gadus morhua) was found to exhibit antimicrobial activity against Bacillus megaterium, Escherichia coli and Candida albicans. This activity varied significantly when salt was added to the antimicrobial assay, and was eliminated by pepsin digestion. No lysozyme activity was detected in the extract. By using weak cationic exchange chromatography together with reversed-phase chromatography, and monitoring the antimicrobial activity, we have isolated four cationic proteins from the mucus extract. Using N-terminal and C-terminal amino acid sequence analysis, together with MS, the antimicrobial proteins were identified as histone H2B (13 565 Da), ribosomal protein L40 (6397 Da), ribosomal protein L36A (12 340 Da) and ribosomal protein L35 (14 215 Da). The broad spectra of antimicrobial activities in the cod mucus and the characterization of four antimicrobial polypeptides suggest that mucus compounds contribute to the innate host defence of cod.
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden. bergsson@here.is
authors.forename: Gudmundur
authors.initials: G
authors.lastname: Bergsson
authors.forename: Birgitta
authors.initials: B
authors.lastname: Agerberth
authors.forename: Hans
authors.initials: H
authors.lastname: Jörnvall
authors.forename: Gudmundur Hrafn
authors.initials: GH
authors.lastname: Gudmundsson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D004817:Epidermis / Q000737:chemistry*; D048389:Gadus morhua; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009093:Mucus / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid; D014020:Tissue Extracts / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D014020:Tissue Extracts