Production of the 57 kDa major surface antigen by a non-agglutinating strain of the fish pathogen Renibacterium salmoninarum

Diseases of Aquatic Organisms

Roselynn M. W. Stevenson¹  Patric R. Senson¹ 

关键词: Renibacterium salmoninarum;    Bacterial kidney disease;    BKD;    Major surface antigen;    p57;    Non-autoagglutinating strains;   

DOI  :  10.3354/dao038023

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: The major surface antigen of Renibacterium salmoninarum, p57, is associated with cell autoagglutination and implicated as a virulence factor in fish infections. An autoagglutinating strain, JD24, caused 92% mortality when 2 x10⁷ cells were injected intraperitoneally into rainbow trout Oncorhynchus mykiss, while a non-agglutinating strain, MT 239, produced only 7% mortality after 100 d. The p57 antigen was present in the supernates of broth cultures ofboth strains when examined by western immunoblotting, and the gene for p57 was detected in both strains by PCR. Electron microscopy of cryopreserved thin sections showed an amorphous layer associated with the cell surface of JD24 which was not seen withMT 239. While p57 from JD24 could reassociate with cells of both strains, p57 from MT 239 failed to restore haemagglutination activity to either strain. Biotinylation of bacterial surfaces demonstrated the presence of a carbohydrate component of p57 fromJD24 which was absent from the p57 produced by MT 239. The higher virulence of JD24 may depend not only on the production of p57, but also its direct association with the bacterial cell surface.

【 授权许可】

Unknown