Identification of two new [beta]-glucosidases of neurospora crassa

A new B-glucosidase, "W1", was demonstrated by electrophoretic analysis to be in conidial washes of several exotic strains of Neurospora crassa. The biochemical and genetic characteristics of "W1" were compared with those of established aryl B-glucosidase and cellobiase in order to study diversity in a species. Aryl B-glucosidase and "W1" in the conidial wash of exotic strain of P-212 were separated by three methods: electrophoresis on cellulose polyacetate, where "W1" was less mobile; Bio-Gel P-200 column fractionation, where "W1" (the smaller enzyme) was eluted last; and calcium phosphate gel adsorption, where aryl B-glucosidase was adsorbed, and " W1" was in the supernatant fraction. The physical properties of "W1" were determined using a purified preparation of "W1" which was obtained after treatment of a conidial wash with calcium phosphate gel. The new enzyme was relatively thermostable at 60 C, with a half-life of 16 - 17 minutes. The enzyme had a pH optimum of 5.0 in potassium phosphate and in citrate phosphate buffer. A Michaelis constant of 1.98 X 10-5 Molar p-nitrophenyl B-D glucose was determined for Neurospora "W1". Although "W1" was found in conidial washes of strains only 72 hours old (the first day of conidiation), attempts to induce the production of " W1" in mycelia of any age were unsuccessful