VACCINIA VIRUS G4L GENE ENCODES A 2ND GLUTAREDOXIN

Vaccinia virus (VV) was previously shown to encode a functional glutar edoxin, the product of the o21 gene, which is synthesized late in infe ction, after the onset of DNA replication. Here we report that an open reading frame in the VV genome designated as g41 encodes a protein th at has sequence similarity to glutaredoxins and possesses thioltransfe rase and dehydroascorbate reductase activities. G4L protein in infecte d cells can be detected as early as 4 hr after infection and is consti tutively expressed up to 24 hr postinfection. A protein homologous to G4L and retaining the predicted glutaredoxin active center is encoded by the recently sequenced Molluscum Contagiosum virus (MCV), whereas O 2L protein is not conserved, suggesting that the glutaredoxin activity of G4L may be involved in replication of ail poxviruses. (C) 1996 Aca demic Press, Inc.