PRODUCTION AND DETECTION OF MURAMIDASE AND ACETYLGLUCOSAMINIDASE FROMAGARICUS-BISPORUS

The production and regulation of extracellular bacteriolytic enzymes o f Agaricus bisporus are being studied to understand better the nutriti on of this fungus and to identify factors that regulate the selectivit y of mushroom compost as a growth medium. Both muramidase (EC.3.2.1.17 ) and N-acetyl-beta-D-glucosaminidase (beta-GlcNAcase, EC.3.2.1.30) ha ve been detected in liquid cultures of A. bisporus, and in cultures fr uiting in sterile and non-sterile compost. A turbidometric assay, base d on the decrease in optical density of suspended Bacillus subtilis ba cterial cell walls, was used to measure muramidase production by A. bi sporus. A colorimetric assay was used to measure beta-GlcNAcase. Both bacteriolytic enzyme activities were produced on a range of sole carbo n sources, including killed freeze-dried B. subtilis cells. Muramidase activity was highest in axenic compost cultures. Bacteriolytic enzyme activity peaked as the first group of fruit bodies was harvested in b oth sterile and non-sterile compost.