title: Detection of antimicrobial peptides related to piscidin 4 in important aquacultured fish.
abstract: Epithelial surfaces of fish, such as the gut, skin and gills, comprise a large surface area for possible pathogen invasion. Antimicrobial peptides (AMPs), innate immunity components, play a significant role in protecting fish. Piscidins are a family of AMPs. In this study, we detected the presence of the recently discovered piscidin 4 via bug blot, Western blot, ELISA and/or immunohistochemistry in striped bass (Morone saxatilis), white bass (M. chrysops), European seabass (Dicentrarchus labrax), gilthead seabream (Sparus aurata), red drum (Sciaenops ocellatus), and barramundi (Lates calcarifer). Via bug blot, gill extracts from all species had antibacterial activity corresponding to the migration rate of piscidin 4. Western blotting showed that piscidin 4 immunoreactivity was greatest in striped bass gill extract. The concentrations of piscidin 4 detected by the ELISA in striped bass gill (approximately 20 microg/ml) were well within the levels that are inhibitory to important fish bacterial pathogens. Piscidin 4 was also detected via immunohistochemistry in all fish except barramundi. Piscidin 4-positive cells were identified as mast cells (MC), but not all MC were piscidin 4-positive. Species, age, size and physiological condition at sampling were some factors that might affect piscidin expression in different species. Our data provide strong evidence that piscidin 4 isoforms are present in all these commercially important species.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA.
authors.forename: Jone
authors.initials: J
authors.lastname: Corrales
authors.forename: Ivan
authors.initials: I
authors.lastname: Mulero
authors.forename: Victoriano
authors.initials: V
authors.lastname: Mulero
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Noga
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis / Q000276:immunology* / Q000378:metabolism; D017756:Aquaculture; D001492:Bass / Q000276:immunology* / Q000378:metabolism; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D029941:Fish Proteins / Q000276:immunology* / Q000378:metabolism; D007150:Immunohistochemistry; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000096:biosynthesis / Q000276:immunology; D021541:Sea Bream / Q000276:immunology* / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D023181:Antimicrobial Cationic Peptides; D029941:Fish Proteins; D020033:Protein Isoforms; C541375:piscidin 4, striped bass