title: Isolation and characterization of rainbow trout C-reactive protein.
abstract: An acute phase serum component, C-reactive protein (CRP), was isolated from the sera of rainbow trout (Salmo gairdneri). The isolation was based on its calcium-dependent binding affinity for pneumococcal C-polysaccharide (CPS) according to the isolation procedure of human C-reactive protein. In SDS-PAGE, the nonreduced CRP showed two subunits with molecular weights of 43,700 and 26,600, respectively, at a molar ratio of 1:1. The reduced CRP showed a single subunit of 26,600. The molecular weight of the native protein was estimated as 66,000 by native gradient PAGE and 81,400 by sedimentation equilibrium analysis using ultracentrifugation. The antigenic determinant on CPS-reactive site was destroyed by periodate oxidation, indicating that rainbow trout CRP is a glycoprotein. CRP levels in rainbow trout serum measured by the CPS-ELISA procedure showed that the rainbow trout CRP could behave as an acute phase reactant, following experimental infection with the fish pathogen Vibrio anguillarum.
authors.affiliation: Department of Epizootiology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Murai
authors.forename: H
authors.initials: H
authors.lastname: Kodama
authors.forename: M
authors.initials: M
authors.lastname: Naiki
authors.forename: T
authors.initials: T
authors.lastname: Mikami
authors.forename: H
authors.initials: H
authors.lastname: Izawa
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002097:C-Reactive Protein / Q000276:immunology / Q000302:isolation & purification*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005393:Fish Diseases / Q000097:blood; D006168:Guinea Pigs; D008970:Molecular Weight; D011817:Rabbits; D012487:Salmonidae / Q000097:blood*; D014337:Trout / Q000097:blood*; D014735:Vibrio Infections / Q000097:blood / Q000662:veterinary
chemical_list: D000596:Amino Acids; D002097:C-Reactive Protein