Expression of herpes simplex virus type I thymidine kinase gene in Escherichia coli

A herpes simplex virus type I DNA fragment containing the sequence coding for thymidine kinase was fused to the very beginning of the Escherichia coli lac Z gene in the three possible reading frames. When the thymidine kinase sequence was in the orientation fit to be transcribed from the lac promoter, functional thymidine kinase was made under lac control in all three cases. Sequences data indicate that translation reinitiation occurs at the 5' end of the thymidine kinase gene after stop signals. Two T+A-rich sequences, which may be part of eukaryotic promoters, are found in the same region.