DAO 30:177-185 (1997)  -  doi:10.3354/dao030177

Purified metallo-protease from the pathogenic haemoflagellate Cryptobia salmositica and its in vitro proteolytic activities

X. Zuo, P. T. K. Woo*

Department of Zoology, University of Guelph, Guelph, Ontario, Canada N1G 2W1
*Addressee for correspondence. E-mail:

The metallo-protease (200 kDa) from Cryptobia salmositica was purified using ion-exchange chromatography and gelfiltration. The purity of the enzyme was confirmed as there was only one homogeneous band using SDS-PAGE. Under in vitro conditions the purified metallo-protease completely degraded the extracellular matrix proteins (collagen types I, IV, V and laminin) and the membrane proteins isolated from rainbow trout erythrocytes. The results confirm that the C. salmositica metallo-protease is a histolytic enzyme and it contributes to salmonid cryptobiosis and to the direct transmission of the parasite between fish.


Cryptobia salmositica · Metallo-protease · Purification · Hydrolysis · Proteins


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