title: Cloning and characterization of an S-formylglutathione hydrolase from Arabidopsis thaliana.
abstract: A cDNA from Arabidopsis thaliana resembling S-formylglutathione hydrolase (SFGH), an enzyme with putative roles in formaldehyde detoxification in animals and microorganisms, has been cloned and expressed in Escherichia coli. The purified recombinant Arabidopsis enzyme (AtSFGH) was a dimer composed of 31-kDa subunits. Like SFGHs from other sources, AtSFGH had thioesterase activity toward S-formylglutathione and carboxyesterase activity toward 4-methylumbelliferyl acetate. Unlike other SFGHs, the enzyme from Arabidopsis actively hydrolyzed S-acetylglutathione. AtSFGH activity was inhibited by heavy metals and sulfhydryl alkylating agents, but was insensitive to serine hydrolase inhibitors, suggesting that the enzyme was a cysteine-dependent hydrolase. Although Atsfgh transcripts were determined in plants and cultures of Arabidopsis, the respective enzyme could not be detected in planta after the esterase activities present were resolved using isoelectric focusing. Instead, Arabidopsis contained several carboxyesterases active toward alpha-naphthyl acetate, which were all sensitive to inhibition by the serine hydrolase inhibitor paraoxon.
authors.affiliation: School of Biological and Biomedical Sciences, University of Durham, Durham DH1 3LE, United Kingdom.
authors.forename: Sandra
authors.initials: S
authors.lastname: Kordic
authors.forename: Ian
authors.initials: I
authors.lastname: Cummins
authors.forename: Robert
authors.initials: R
authors.lastname: Edwards
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D043182:Carboxylesterase; D003001:Cloning, Molecular; D004950:Esterases / Q000378:metabolism; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013869:Thiolester Hydrolases / Q000235:genetics* / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D004950:Esterases; D043182:Carboxylesterase; C020118:ESD protein, human; D013869:Thiolester Hydrolases; C020149:s-formylglutathione hydrolase