Li_2014_J.Biol.Chem_289_19031

Reference

Title : Structural Basis for Dimerization and Catalysis of a Novel Esterase from the GTSAG Motif Subfamily of the Bacterial Hormone-sensitive Lipase Family - Li_2014_J.Biol.Chem_289_19031
Author(s) : Li PY , Ji P , Li CY , Zhang Y , Wang GL , Zhang XY , Xie BB , Qin QL , Chen XL , Zhou BC , Zhang YZ
Ref : Journal of Biological Chemistry , 289 :19031 , 2014
Abstract :

Hormone-sensitive lipases (HSLs) are widely distributed in microorganisms, plants, and animals. Microbial HSLs are classified into two subfamilies, an unnamed new subfamily and the GDSAG motif subfamily. Due to the lack of structural information, the detailed catalytic mechanism of the new subfamily is not yet clarified. Based on sequence analysis, we propose to name the new subfamily as the GTSAG motif subfamily. We identified a novel HSL esterase E25, a member of the GTSAG motif subfamily, by functional metagenomic screening, and resolved its structure at 2.05 A. E25 is mesophilic (optimum temperature at 50 degrees C), salt-tolerant, slightly alkaline (optimum pH at 8.5) for its activity, and capable of hydrolyzing short chain monoesters (C2-C10). E25 tends to form dimers both in the crystal and in solution. An E25 monomer contains an N-terminal CAP domain, and a classical alpha/beta hydrolase-fold domain. Residues Ser186, Asp282, and His312 comprise the catalytic triad. Structural and mutational analyses indicated that E25 adopts a dimerization pattern distinct from other HSLs. E25 dimer is mainly stabilized by an N-terminal loop intersection from the CAP domains and hydrogen bonds and salt bridges involving seven highly conserved hydrophilic residues from the catalytic domains. Further analysis indicated that E25 also has some catalytic profiles different from other HSLs. Dimerization is essential for E25 to exert its catalytic activity by keeping the accurate orientation of the catalytic Asp282 within the catalytic triad. Our results reveal the structural basis for dimerization and catalysis of an esterase from the GTSAG motif subfamily of the HSL family.

PubMedSearch : Li_2014_J.Biol.Chem_289_19031
PubMedID: 24867954
Gene_locus related to this paper: 9bact-E25

Related information

Gene_locus 9bact-E25
Family GTSAGmotif
Structure 4Q05

Citations formats

Li PY, Ji P, Li CY, Zhang Y, Wang GL, Zhang XY, Xie BB, Qin QL, Chen XL, Zhou BC, Zhang YZ (2014)
Structural Basis for Dimerization and Catalysis of a Novel Esterase from the GTSAG Motif Subfamily of the Bacterial Hormone-sensitive Lipase Family
Journal of Biological Chemistry 289 :19031

Li PY, Ji P, Li CY, Zhang Y, Wang GL, Zhang XY, Xie BB, Qin QL, Chen XL, Zhou BC, Zhang YZ (2014)
Journal of Biological Chemistry 289 :19031