Mapping of the thymidine kinase genes of type 1 and type 2 herpes simplex viruses using intertypic recombinants.

The thymidine kinase induced in lytic infection by each of 36 intertypic recombinants of herpes simplex virus (HSV) type 1 and type 2 was identified as type 1 or type 2 by studies on the thermolability of enzyme activity, neutralization with type 1 or type 2 antiserum and agar gel immunodiffusion with type 1 or type 2 thymidine kinase antiserum. Fourteen recombinants induced no thymidine kinase, 12 induced type 1 thymidine kinase and 10 induced type 2 thymidine kinase. Correlation of these results with restriction endonuclease analysis of the DNA of the recombinants with five restriction endonucleases (XbaI, EcoRI, HpaI, HsuI, and Bg/II) allowed mapping of the type 1 thymidine kinase gene at 0.300 to 0.309 map unit and the type 2 thymidine kinase gene at 0.295 to 0.315 map unit.