Glutaredoxin homolog encoded by vaccinia virus is a virion-associated enzyme with thioltransferase and dehydroascorbate reductase activities.
Glutaredoxins (GRXs), also known as thioltransferases, use glutathione as a cofactor for reduction of disulfides in prokaryotes and eukaryotes. We demonstrate that the vaccinia virus O2L open reading frame encodes a functional GRX, as predicted by Johnson et al. [Johnson, G. P., Goebel, S. J., Perkus, M. E., Davis, S. W., Winslow, J. P. & Paoletti, E. (1991) Virology 181, 378-381] from sequence homology. The 12-kDa protein product of the O2L open reading frame was synthesized after viral DNA replication, coincident with a major increase in cytoplasmic glutathione-dependent thioltransferase activity. The protein was associated with purified vaccinia virions and was not released by treatment with a nonionic detergent unless dithiothreitol was added. The virion-derived protein, as well as a recombinant form expressed in Escherichia coli, exhibited thioltransferase and dehydroascorbate reductase activities indicative of a functional GRX. The postreplicative synthesis of vaccinia virus GRX and its association with virions suggest that the enzyme may have novel roles in the virus growth cycle.
Ahn
B Y
BY
Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892.
Moss
B
B
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D054477:Glutaredoxins; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009250:NADP Transhydrogenases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D009838:Oligodeoxyribonucleotides; D016366:Open Reading Frames; D010088:Oxidoreductases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D011490:Protein Disulfide Reductase (Glutathione); D011506:Proteins / Q000235:genetics* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D014616:Vaccinia virus / Q000201:enzymology / Q000235:genetics*; D010948:Viral Plaque Assay; D014771:Virion / Q000201:enzymology / Q000235:genetics*
D001426:Bacterial Proteins; C516005:GLRX protein, human; D054477:Glutaredoxins; D009838:Oligodeoxyribonucleotides; D011506:Proteins; D011994:Recombinant Proteins; D010088:Oxidoreductases; D009250:NADP Transhydrogenases; D011490:Protein Disulfide Reductase (Glutathione); C020666:glutathione dehydrogenase (ascorbate)