crystal structure of a novel esterase rv0045c from mycobacterium tuberculosis晶体结构的一种新型酯酶rv0045c结核分枝杆菌.pdf

Crystal Structure of a Novel Esterase Rv0045c from Mycobacterium tuberculosis 1,2. 1,2. 1 1 3 4 4 Xiangdong Zheng , Jiubiao Guo , Lipeng Xu , Honglei Li , Dongwei Zhang , Kai Zhang , Fei Sun , 5 2 1 Tingyi Wen , Siguo Liu *, Hai Pang * 1 School of Medicine, Tsinghua University, Beijing, China, 2 Harbin Veterinary Research Institute, Chinese Academy of Agriculture, Harbin, China, 3 Department of Oral Biological and Medical Sciences, University of British Columbia, Vancouver, Canada, 4 Institute of Biophysics, Chinese Academy of Sciences, Beijing, China, 5 Department of Industrial Microbiology and Biotechnology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China Abstract There are at least 250 enzymes in Mycobacterium tuberculosis (M. tuberculosis) involved in lipid metabolism. Some of the enzymes are required for bacterial survival and full virulence. The esterase Rv0045c shares little amino acid sequence similarity with other members of the esterase/lipase family. Here, we report the 3D structure of Rv0045c. Our studies demonstrated that Rv0045c is a novel member of a/ b hydrolase fold family. The structure of esterase Rv0045c contains two distinct domains: the a/ b fold domain and the cap domain. The active site of esterase Rv0045c is highly conserved and comprised of two residues: Ser154 and His309. We proposed that Rv0045c probably employs two kinds of enzymatic mechanisms when hydrolyzing C-O ester bonds within substrates. The structure provides insight into the hydrolysis mechanism of the C-O ester bond, and will be helpful in understanding the ester/lipid metabolism