Interaction of coho salmon Oncorhynchus kisutch egg lectin with the fish pathogen Aeromonas salmonicida

摘要

The yolk of coho salmon Oncorhynchus kisutch eggs contains a galactophilic lectin which proved capable of binding to Aeromonassalmonicida, the causative agent of furunculosis in salmonids. Immunofluorescence staining of whole bacterial cells, and western blot analysis of cellular fractions from various phenotypes of A. salmonicida, revealed that the lipopolysaccharide's core region and other soluble proteins and/or glycoproteins were the bacterial lectin-binding sites. The protective role of the egg's lectin was investigated by testing the lectin for its ability to prevent growth of A. salmonicida. The lectin did not show antibacterial activities against any of the tested strains of A. salmonicida. It was concluded that the lectin's role lay in some direction other than protection against disease agents.