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 α-naphthyl acetate, which were all sensitive to inhibition by the serine hydrolase inhibitor paraoxon.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.