title: Molecular cloning and characterization of a sigma-class glutathione S-transferase from the freshwater mussel Hyriopsis cumingii.
abstract: A full-length cDNA of a sigma-like glutathione S-transferase (GST) was identified from Hyriopsis cumingii (HcGSTS). The deduced amino acid sequence of HcGSTS was found to comprise 203 amino acid residues and to contain the distinct highly conserved glutathione binding site of N-terminal and the relatively diverse substrate binding site of C-terminal. Alignment analysis and phylogenetic relationship suggested that the HcGSTS is a sigma-class GST. The mRNA of HcGSTS was constitutively expressed in all tested tissues, the strongest expression being in the hepatopancreas. The mRNA expression of HcGSTS was significantly up-regulated (P < 0.05) in all assessed tissues after stimulation of the mussels with peptidoglycan (PGN) and LPS, the only exception being when the gills were challenged with PGN. The expression of HcGSTS mRNA in kidney and foot was also significantly up-regulated (P < 0.05) by microcystin-LR. Recombinant HcGSTS exhibited high activity towards the substrate 1-chloro-2,4-dinitrobenzene. The optimal pH was 8.0 and temperature 35 °C.
authors.affiliation: Key Laboratory of Northwest Water Resources and Environmental Ecology of Education Ministry, Xi'an University of Technology, Xi'an, Shanxi Province, 710048, China; School of Environment and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, Henan Province, 450011, China.
authors.forename: Haihua
authors.initials: H
authors.lastname: Li
authors.forename: Ziyan
authors.initials: Z
authors.lastname: Yang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Huang
authors.forename: Yanxia
authors.initials: Y
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D049872:Bivalvia / Q000737:chemistry / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D004795:Enzyme Stability; D005982:Glutathione Transferase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D005982:Glutathione Transferase
keywords: Hyriopsis cumingii; biochemical characterization; expression pattern; glutathione S-transferase