ISOLATION AND CHARACTERIZATION OF NUCLEOSIDE DIPHOSPHATE KINASE FROM THE PATHOGENIC FUNGUS CANDIDA-ALBICANS

Nucleoside diphosphate kinase (NDPK) was isolated and characterized fr om soluble extracts of the fungus Candida albicans. The enzyme was par tially purified through Blue-Sepharose, and Q-Sepharose chromatography . Its native Mr estimated by sucrose gradient and gel filtration was 9 9 kDa. The Mr of the subunits estimated in Western blots by immunodete ction with an heterologus antibody was 17 kDa anal indicating that the native enzyme is an hexamer. Variations of especific activity as well as enzyme expression was assessed during the yeast phase of growth an d during morphogenetic transitions. The results indicate that the enzy me was maximally expressed at the logarithmic stage of the yeast life cycle. NDPK activity was also detected in the extracellular fluid at t he late stationary stage.