Herpes simplex virus type 1 uracil-DNA glycosylase: isolation and selective inhibition by novel uracil derivatives.

Abstract

We have purified Herpes simplex type 1 (HSV1) uracil-DNA glycosylase from the nuclei of HSV1-infected HeLa cells harvested 8 h post-infection, at which time the induction of the enzyme is a maximum. The enzyme has been shown to be distinct from the host enzyme, isolated from HeLa cells, by its lack of sensitivity to a monoclonal antibody to human uracil-DNA glycosylase. Furthermore, several uracil analogues were synthesized and screened for their capacity to discriminate between the viral and human uracil-DNA glycosylases. Both enzymes were inhibited by 6-(p-alkylanilino)uracils, but the viral enzyme was significantly more sensitive than the HeLa enzyme to most analogues. Substituents providing the best inhibitors of HSV1 uracil-DNA glycosylase were found to be in the order: p-n-butyl < p-n-pentl = p-n-hexyl < p-n-heptyl < p-n-octyl. The most potent HSV1 enzyme inhibitor, 6-(p-n-octylanilino)uracil (OctAU), with an IC50 of 8 microM, was highly selective for the viral enzyme. Short-term [3H]thymidine incorporation into the DNA of HeLa cells in culture was partially inhibited by OctAU, whereas it was unchanged when 6-(p-n-hexylanilino)uracil was present at concentrations that completely inhibited HSV1 uracil-DNA glycosylase activity. These compounds represent the first class of inhibitors that inhibit HSV1 uracil-DNA glycosylase at concentrations in the micromolar range. The results suggest their possible use to evaluate the functional role of HSV1 uracil-DNA glycosylase in viral infections and re-activation in nerve cells.

• Authors: F Focher, A Verri, S Spadari, R Manservigi, J Gambino, G E Wright
• Journal: The Biochemical journal (Biochem J) Vol. 292 ( Pt 3) Pg. 883-9 (Jun 15 1993) ISSN: 0264-6021 [Print] England
• PMID: 8391260 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• 6-(N-octylanilino)uracil
• Uracil
• DNA Glycosylases
• N-Glycosyl Hydrolases
• Uracil-DNA Glycosidase
• Thymidine

Topics

• Cell Nucleus (enzymology)
• DNA Glycosylases
• DNA Repair
• Electrophoresis, Polyacrylamide Gel
• HeLa Cells
• Humans
• Kinetics
• N-Glycosyl Hydrolases (antagonists & inhibitors, isolation & purification)
• Simplexvirus (enzymology)
• Structure-Activity Relationship
• Thymidine (metabolism)
• Uracil (analogs & derivatives, pharmacology)
• Uracil-DNA Glycosidase