IDENTIFICATION OF ELECTROPHORETICALLY SEPARATED PROTEASES FROM MIDGUTAND HEMOLYMPH OF ADULT ANOPHELES-STEPHENSI MOSQUITOS

Digestion of blood within the mosquito midgut is mediated primarily by a series of proteases, and several previous studies have described pr otease activity within homogenates of the midgut of the malaria vector Anopheles stephensi. We have expanded on these previous data by resol ving protease isoforms from the midgut as well as the hemolymph of adu lt An. stephensi mosquitoes via gel electrophoresis and zymography. Us ing this procedure, we have been able to identify multiple isozymes of trypsin, chymotrypsin, and aminopeptidase. We were able to detect an increase in the intensity of some of these protease bands plus the app earance of new bands 24 hr after mosquitoes had taken a blood meal. Fu rthermore, we detected 2 endogenous trypsin isozymes within the hemoly mph. There was no upregulation of these hemolymph isozymes after a blo od meal, thus suggesting that they may not be involved in digestion of the blood meal by the mosquito.