FIG. 1.

Schematic representation of the construction of recombinant viruses. 1, fragment of HSV-1(F) BamHI N sequence in plasmid pRB5210 showing the wild-type ICP22 ORF (open rectangle); 2, deletion of ICP22 ORF from the initiation methionine codon to the carboxyl-terminal stop codon in the deletion virus R7802 and in plasmid pRB5212, leaving only a single EagI site; 3, mutant ICP22 sequence (hatched rectangle) excised from mutated pRB5252 by digestion with EagI and inserted into the unique EagI site in pRB5212; 4, resultant plasmid containing the inserted mutated ICP22 ORF, used to rescue ICP22 deletion virus R7802 for isolation of recombinant viruses R7827, R7837, R7851, and R7855. R7853, R7854, and R7855 were isolated from the same transfection stock. The mutated amino acid sequences present in these recombinant viruses are shown in Table 1. Abbreviations: B, BamHI; E, EcoRI.