The Effect of Zinc Cations on LipN of Mycobacterium ulcerans

Indianapolis, IN

LipN is a serine hydrolase from Mycobacterium ulcerans. The mycobacterium causes Buruli ulcer, a soft-tissue and skin disease which leads to permanent disabilities and disfigurements. LipN was overexpressed in E. coli, purified, and its identity confirmed by gel electrophoresis. Zinc cations were tested as inhibitors of the enzymatic activity of LipN as measured by the hydrolysis of a fluorogenic ester. The enzyme kinetic constants were not significantly altered by the presence of the metal cations. The results, in contrast to preliminary data, indicate that zinc cations do not affect the function of LipN as a catalyst for the reaction. This data contributes to the knowledge of LipN and other proteins in its family of bacterial serine hydrolases.