An increase in catalase activity accompanied by microbody development in wounded sweet potato root tissue was investigated with a specific antibody against sweet potato catalase. The increase was completely inhibited by cycloheximide. Analysis with single radial immunodiffusion method showed that protein immunoprecipitated by the antibody increased in wounded tissue, indicating the involvement of de novo synthesis of catalase protein in the activity-increase. The activity-increase was, however, more remarkable than the increase in immunoreactive protein and this results in an increase in specific catalase activity in wounded tissue, indicating the presence in intact tissue of an inert or less active protein, immunologically analogous to catalase. Actually, immunological analysis showed the presence in intact tissue of an immunoreactive protein which differed from active catalase protein in the mobility on a polyacrylamide gel and probably also in the molecular weight of subunit. The immunoreactive protein seemed to exist in a significant amount outside the microbodies in intact tissue cells. Thus, there is a possibility that the increase in catalase activity in wounded tissue is partly due to activation of the immunoreactive protein.
展开▼
