Purification of a Lethal Toxin of Edwardsiella tarda

Suprapto Hari

Hara Takaaki

Nakai Toshihiro

Muroga Kiyokuni

魚病研究

Fish Pathology

A toxin lethal to fish was purified from extracellular products (ECP) of Edwardsiella tarda by ion exchange chromatography and gel filtration. The purified toxin is a protein having proteolytic activities and lethal toxicity to Japanese eel Anguilla japonica with the LD50 of 1.6µg per g of fish body weight. Molecular weight of the protein was estimated to be 37 kDa by SDS-PAGE. SDS-PAGE, Western blot and imrnunodiffusion analyses revealed that the 37 kDa protein was present in the ECP and ICC (intracellular components) of virulent strains of E. tardy but not in those of avirulent strains, indicating that this toxin plays an important role in the pathogenicity of E. tarda.

Edwardsiella tarda

toxin

extracellular product

intracellular component

Japanese eel

ECP

水産業 [ 660 ]

英語

日本魚病学会

[ISSN] 0388-788X

[NCID] AN00063165