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Rice plants have three homologs of glutathione synthetase genes, one of which, OsGS2, codes for hydroxymethyl-glutathione synthetase.

ABSTRACT: Glutathione is a ubiquitous thiol tripeptide in land plants, and glutathione-like tripeptides can also be found in some plant species. Rice (Oryza sativa) plants synthesize hydroxymethyl-glutathione, in which the terminal glycine residue of glutathione is replaced by a serine residue; however, the biosynthetic pathway of hydroxymethyl-glutathione has not been identified. We isolated three rice glutathione synthetase homologs, designated OsGS1, OsGS2, and OsGS3, and found that knockdown of OsGS2 via RNA interference markedly decreased hydroxymethyl-glutathione concentration in rice plants. The in vitro enzyme assay, using purified recombinant protein, demonstrated that OsGS2 catalyzed the synthesis of hydroxymethyl-glutathione from ?-glutamylcysteine (?EC) and L-serine in an ATP-dependent manner. OsGS2 could also utilize glycine as a cosubstrate with ?EC, but the enzyme-substrate affinity for L-serine was tenfold higher than that for glycine. These results indicate that OsGS2 codes for hydroxymethyl-glutathione synthetase.

SUBMITTER: Yamazaki S

PROVIDER: S-EPMC6508825 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Rice plants have three homologs of glutathione synthetase genes, one of which, <i>OsGS2</i>, codes for hydroxymethyl-glutathione synthetase.

Yamazaki Shinichi S Ochiai Kumiko K Matoh Toru T

Plant direct 20190218 2

Glutathione is a ubiquitous thiol tripeptide in land plants, and glutathione-like tripeptides can also be found in some plant species. Rice (<i>Oryza sativa</i>) plants synthesize hydroxymethyl-glutathione, in which the terminal glycine residue of glutathione is replaced by a serine residue; however, the biosynthetic pathway of hydroxymethyl-glutathione has not been identified. We isolated three rice glutathione synthetase homologs, designated OsGS1, OsGS2, and OsGS3, and found that knockdown of ...[more]

PMID: 31245762

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Dataset Information

Rice plants have three homologs of glutathione synthetase genes, one of which, OsGS2, codes for hydroxymethyl-glutathione synthetase.

Publications

Rice plants have three homologs of glutathione synthetase genes, one of which, <i>OsGS2</i>, codes for hydroxymethyl-glutathione synthetase.

Similar Datasets

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