The herpes simplex virus 1 origin binding protein: a DNA helicase.

A recombinant herpes simplex 1 origin binding protein, the product of the herpes UL9 gene, has been overexpressed in mammalian cells and purified to near homogeneity. The origin binding protein shows DNA-dependent nucleoside 5'-triphosphatase and DNA helicase activities in addition to its origin binding activity. The ability to hydrolyze nucleoside 5'-triphosphates is influenced strongly by the structure and sequence of the DNA cofactor. The properties of the recombinant origin binding protein are identical to those of the protein synthesized in herpes simplex 1-infected mammalian cells.