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Crystal structure of a novel esterase Rv0045c from Mycobacterium tuberculosis.

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 ?/? hydrolase fold family. The structure of esterase Rv0045c contains two distinct domains: the ?/? 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 in M. tuberculosis.

SUBMITTER: Zheng X

PROVIDER: S-EPMC3102732 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Crystal structure of a novel esterase Rv0045c from Mycobacterium tuberculosis.

Zheng Xiangdong X Guo Jiubiao J Xu Lipeng L Li Honglei H Zhang Dongwei D Zhang Kai K Sun Fei F Wen Tingyi T Liu Siguo S Pang Hai H

PloS one 20110526 5

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 α/β hydrolase fold family. The structure of esterase Rv0045c contains two distinct domains: the ...[more]

PMID: 21637775

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