TWENTY-FIFTH ANNUAL EASTERN FISH HEALTH WORKSHOP MARCH 10-13, 2000   Collagenases Of Marine Eukaryotes: Role In Disease Processes And Potential Uses In Biotechnology     Mohamed Faisal1, B.D. Tall2, Sherill K. Curtis2, A. Shaheen3, and S.M. McLaughlin4   1Virginia Institute of Marine Science, School of Marine Science, The College of William and Mary, Gloucester Point, VA 23062; 2Food and Drug Administration, Microbial Ecology Branch, 200 C St., S.W., Washington, DC  20204; 3Faculty of Veterinary Medicine at Moshtohor, Benha, Egypt; 4NOAA, National Ocean Service, Center for Coastal Environmental Health and Biomolecular Research, Cooperative Oxford Laboratory, 904 S. Morris St., Oxford, MD  21654     Most recently, an interest has grown in studying proteases secreted by marine organisms.  In addition to their applications in biotechnology, it is believed that they play a role in the emergence of new diseases and massive mortalities in the aquatic environment. Of special importance are proteases with collagenolytic activities because of their wide industrial and commercial applications and known role in disease pathogenesis.  Herein, we describe some characteristics of collagenases produced by several eukaryotes from the Chesapeake Bay.  Our earlier studies have demonstrated that the oyster pathogenic protozoan, Perkinsus marinus, secretes a multitude of serine proteases including Perkinsin, a major 41.7 kDa, N-glycosylated collagenase.  Investigations have demonstrated that Perkinsin has an unusually wider salinity and temperature ranges than those known for other marine protozoa. Recently, we isolated a Labyrinthuloides sp. from the softshell clam, Mya arenaria, with disseminated sarcoma. The organism produces copious layers of thick exopolysaccharides in which the protozoal cells are completely enveloped. The parasite also secretes two high molecular weight serine collagenases (120 and 90 kDa) with extraordinarily high specific activities. Thus, these results  suggest a relationship between the intiation of the sarcoma and pathology of Labyrinthuloisis.  Most recently, a non-septated Oomycete fungus, Aphanomyces sp., parasitizing deep muscles of ulcerated Atlantic menhaden, Brevoortia tyrannus, has been isolated. Analyses of the extracellular proteins of this fungal isolate demonstrated the presence of four collagenases. Further analysis demonstrated that three of these collagenases are in the serine protease family.  The fourth proteolytic band displayed two unique characteristics. First, proteolytic activity was not inhibited by any of the known protease inhibitors indicating its novel nature. Second, boiling (for 5 minutes) did not inhibit proteolytic activity suggesting a remarkable thermostability.  Together, these results suggest that the disease caused by this organism may involve a complex etiology.   Return to 25th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page