Abstract: | Sequence analysis within the unique long segment of the bovine herpesvirus 1 (BHV-1) genome previously identified an open reading frame (ORF), designated UL2, whose deduced polypeptide of 204 amino acids contained a consensus uracil-DNA glycosylase (UDGase) signature sequence. To determine whether the BHV-1 UL2 ORF product has UDGase activity, we positioned the UL2 sequence downstream of the T7 promoter on the vector pET-28b(+) and expressed it in Escherichia coli. Upon induction with isopropyl β-D -thiogalactopyranoside these cells produced a 23-kDa protein, the molecular mass of which was in accordance with the prediction from the nucleotide sequence. A one-step purification procedure using nickel-chelating affinity chromatography resulted in a homogeneous preparation of this protein, which displayed specific UDGase activity in an in vitro enzyme assay. These results provide evidence that the BHV-1 UL2 gene does encode a UDGase. |