Determination of virulence associated immunogenic proteins in some of Lactococcus garvieae strains

Lactococcosis disease incident caused by Lactococcus garvieae has been increased with increasing aquaculture productions and outbreaks of the disease have become a threat on farmed species. To prevent lactococcosis, inactivated vaccine has been used, however, it only provides protection when given by injection. Other than inactivated vaccine, various vaccines such as subunit vaccines can be developed. In the present study, total protein profile of ۴۳ strains of L. garvieae isolated from fish, milk and cheese by SDS-PAGE and virulence associated immunogenic proteins of L. garvieae strains using western blot with hyper-immune rabbit sera were determined. After analyzing whole-cell lysate protein of L. garvieae strains with SDS-PAGE, protein bands were ranged between ۸.۰۰ and ۱۴۰.۰۰ kDA. Among strains, variable protein bands were ranged between ۱۷.۰۰ and ۴۸.۰۰ kDa with some variability in the staining intensity of the protein bands and formed in ۶ clusters. The immunogenic protein bands were ranged between ۲۵.۰۰ - ۷۵.۰۰ kDa. Only a variable and highly immunogenic protein band was observed between ۴۰.۰۰ and ۴۵.۰۰ kDa. Most of the strain including Lgper had ۴۴.۰۰ kDa immunogenic protein while nonvirulent ATCC strain had ۴۲.۵۰ kDA immunogenic protein. Predominant immuno-reactive proteins encoded by genes can be used as a subunit vaccine.

کلیدواژه ها:

immunogenic protein ، Lactococcosis ، Rainbow trout ، Western blot ، Yellowtail