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Epsilon glutathione transferases possess a unique class-conserved subunit interface motif that directly interacts with glutathione in the active site.

ABSTRACT: Epsilon class glutathione transferases (GSTs) have been shown to contribute significantly to insecticide resistance. We report a new Epsilon class protein crystal structure from Drosophila melanogaster for the glutathione transferase DmGSTE6. The structure reveals a novel Epsilon clasp motif that is conserved across hundreds of millions of years of evolution of the insect Diptera order. This histidine-serine motif lies in the subunit interface and appears to contribute to quaternary stability as well as directly connecting the two glutathiones in the active sites of this dimeric enzyme.

SUBMITTER: Wongsantichon J

PROVIDER: S-EPMC4660579 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Epsilon glutathione transferases possess a unique class-conserved subunit interface motif that directly interacts with glutathione in the active site.

Wongsantichon Jantana J Robinson Robert C RC Ketterman Albert J AJ

Bioscience reports 20151020 6

Epsilon class glutathione transferases (GSTs) have been shown to contribute significantly to insecticide resistance. We report a new Epsilon class protein crystal structure from Drosophila melanogaster for the glutathione transferase DmGSTE6. The structure reveals a novel Epsilon clasp motif that is conserved across hundreds of millions of years of evolution of the insect Diptera order. This histidine-serine motif lies in the subunit interface and appears to contribute to quaternary stability as ...[more]

PMID: 26487708

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Differences in the subunit interface residues of alternatively spliced glutathione transferases affects catalytic and structural functions.

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Comparison of epsilon- and delta-class glutathione S-transferases: the crystal structures of the glutathione S-transferases DmGSTE6 and DmGSTE7 from Drosophila melanogaster.

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A functionally conserved basic residue in glutathione transferases interacts with the glycine moiety of glutathione and is pivotal for enzyme catalysis.

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MDM2 interacts with the C-terminus of the catalytic subunit of DNA polymerase epsilon.

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