Abstract
The herpes simplex virus type 1 (HSV-1) origin binding protein, the product of the UL9 gene, catalyzes the unwinding of DNA in the 3′-5′ direction. Helicase activity is coupled to the hydrolysis of ATP or dATP and to a lesser extent to CTP, dCTP, or UTP. It requires a divalent cation (Mg2+ > Mn2+ > Ca2+) with an optimum at 2.5 mM MgCl. Activity is optimal at high pH (8.5-9.5) and high temperature (45°C) and is inhibited at ionic strengths > 50 mM NaCl. The helicase activity is specifically stimulated by the HSV-1-encoded single-stranded DNA-binding protein, ICP8, which increases both the rate and extent of helicase activity. Helicase action appears to be stoichiometric, requiring a DNA-dependent assembly of a multimeric UL9 protein complex. Under optimal conditions, the rate of DNA unwinding is approximately 75 base pairs/min.
Original language | English (US) |
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Pages (from-to) | 1220-1225 |
Number of pages | 6 |
Journal | Journal of Biological Chemistry |
Volume | 268 |
Issue number | 2 |
State | Published - Jan 15 1993 |
Externally published | Yes |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology