Submitted to: American Society of Sugarbeet Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 2/3/2003
Publication Date: 2/17/2003
Citation: EILAND, J.J. PROTEASE SECRETION IN APHANOMYCES COCHLIOIDES. ABSTRACTS OF JOINT MEETING OF INTERNATIONAL INSTITUTE FOR BEET RESEARCH AND THE AMERICAN SOCIETY OF SUGARBEET TECHNOLOGISTS. 2003. ABSTRACT P.65.
Technical Abstract: Protease activities have been implicated in the infection of fish and crayfish by Aphanomyces astaci, a pathogen of these host organisms. In an effort to characterize protease activities produced by the sugarbeet pathogen A. cochlioides, culture supernatants of this oomycete were tested for bulk enzyme activity and examined for protease isozyme complement. Bulk protease activity was readily detected using azocoll as a colorimetric substrate. At least 8 distinct isoforms of protease secreted by A. cochlioides were detected after electrophoretic fractionation in native polyacrylamide gels containing co-polymerized gelatin. A subset of the protease activities was sensitive to inhibitors of trypsin, including the proteinacious trypsin inhibitors from lima bean. Co-culture of sugarbeet seedlings in the presence of A. cochlioides and lima bean trypsin inhibitor resulted in increased seedling survival relative to control inoculations. The data suggest that protease activities secreted by A. cochlioides may be virulence determinants in the infection of sugarbeet by this pathogen.