Cloning of the active thymidine kinase gene of herpes simplex virus type 1 in Escherichia coli K-12.

Abstract
A herpes simplex virus DNA fragment that is produced by digestion with BamHI endonuclease and carries the thymidine kinase (TK; ATP:thymidine 5''-phosphotransferase, EC 2.7.1.21) gene was cloned in E. coli. A recombinant plasmid, pFG5, was analyzed extensively and a detailed restriction map is presented. pFG5 DNA efficiently transforms TK- mouse [fibroblast] L cells. The TK coding sequence in the cloned fragment was localized and a smaller recombinant plasmid, pAG0, also carrying an active TK gene, was constructed to serve as a more convenient vector for transfer, into TK- cells, of genes previously cloned in E. coli.