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Published on: July 11, 2016
Crystal structure of the nicotinamidase/pyrazinamidase PncA from Bacillus subtilis
Fei Shang1, Jinli Chen1, Lulu Wang2
1Department of Bioengineering, College of Life Science, Dalian Minzu University, Dalian, 116600, Liaoning, China; Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, China.
Abstract:
The nicotinamidase/pyrazinamidase PncA is a member of a large family of hydrolase enzymes that catalyze the deamination of nicotinamide to nicotinic acid. PncA also functions as a pyrazinamidase in a wide variety of eubacteria and is an essential coenzyme in many cellular redox reactions in living systems. We report the crystal structure of substrate-free PncA from Bacillus subtilis (BsPncA) at 2.0 Å resolution to improve our understanding of the PncA family. The structure of BsPncA consists of an α/β domain and a subdomain. The subdomain of BsPncA has a different conformation than that of PncA enzymes from other organisms. The B-factor analysis revealed a rigid structure of the α/β domain, while the subdomain is highly flexible. Both dimers and tetramers were observed in BsPncA protein crystals, but only dimers were observed in solution. Our results provide useful information that will further enhance our understanding of the molecular functions of PncA family members.
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