The extracellular proteolytic enzymes of the mosquito-parasitizing fungus Lagenidium giganteum

Lagenidium giganteum produces extracellular proteases when grown in peptone-yeast extract-glucose medium. The production of the enzymes required a suitable inducer such as protein, and was repressed by glucose. The total filtrate proteases had a pH optimum of 8.4, and were heat denatured t 60°C. The use of specific substrates and inhibitors demonstrated the presence of collagenase, trypsin-like protease, and a weak elastase. Trypsin-like activity was present in the medium after 38 h of growth, whereas collagenase appeared in 43 h. The roles of these enzymes in pathogenesis were discussed.