Herpes simplex virus type 1 DNA polymerase. Mechanism-based affinity chromatography.
The potent inhibition of herpes simplex type 1 (HSV-1) DNA polymerase by acyclovir triphosphate has previously been shown to be due to the formation of a dead-end complex upon binding of the next 2'-deoxynucleoside 5'-triphosphate encoded by the template after incorporation of acyclovir monophosphate into the 3'-end of the primer (Reardon, J. E., and Spector, T. (1989) J. Biol. Chem. 264, 7405-7411). This mechanism of inhibition of HSV-1 DNA polymerase has been used here to design an affinity column for the enzyme. A DNA hook template-primer containing an acyclovir monophosphate residue on the 3'-primer terminus has been synthesized and attached to a resin support. In the absence of added nucleotides, the column behaves as a simple DNA-agarose column, and HSV-1 DNA polymerase can be chromatographed using a salt gradient. The presence of the next required nucleotide encoded by the template (dGTP) increases the affinity of HSV-1 DNA polymerase for the acyclovir monophosphate terminal primer-template attached to the resin, and the enzyme is retained even in the presence of 1 M salt. The enzyme can be eluted from the column with a salt gradient after removal of the nucleotide from the buffer. Traditionally, the affinity purification of an enzyme relies on elution by a salt gradient, pH gradient, or more selectively by addition of a competing ligand (substrate/inhibitor) to the elution buffer. In the present example, elution of HSV-1 polymerase is facilitated by removal of the substrate from the buffer. This represents an example of mechanism-based affinity chromatography.
Reardon
J E
JE
Experimental Therapy Division, Wellcome Research Laboratories, Research Triangle Park, North Carolina 27709.
D000212:Acyclovir / Q000031:analogs & derivatives / Q000494:pharmacology; D000998:Antiviral Agents / Q000494:pharmacology; D001483:Base Sequence; D002846:Chromatography, Affinity; D004259:DNA-Directed DNA Polymerase / Q000302:isolation & purification* / Q000378:metabolism; D006367:HeLa Cells / Q000201:enzymology; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D019384:Nucleic Acid Synthesis Inhibitors; D009841:Oligonucleotides / Q000138:chemical synthesis; D018139:Simplexvirus / Q000201:enzymology*; D013698:Templates, Genetic
D000998:Antiviral Agents; D019384:Nucleic Acid Synthesis Inhibitors; D009841:Oligonucleotides; C026145:acyclovir monophosphate; C025114:acyclovir triphosphate; D004259:DNA-Directed DNA Polymerase; D000212:Acyclovir