The DNAs of wild-type rabbitpox virus ( . ), and selected (white pock, ) and (white pock, PK-15 cell non-permissive, ) mutants were compared by restriction enzyme analysis. The cleavage fragments produced by digestion with dIII or R1 endonucleases were separated by agarose gel electrophoresis. Deletions of approx. 10 × 10 were recognized at the right-hand terminus of each mutant (three isolates), whereas deletions of 5 × 10 to 20 × 10 were detected at the left-hand terminus of each mutant (nine isolates). Rapidly renaturing terminal restriction fragments, indicative of the covalent cross-links, were only found at the terminus unaffected by deleted sequences. Recombinant viruses that were wild-type in both genetic characters and in restriction pattern were recovered from mixed infections involving and mutants, but no genetic interaction was detected between crosses involving only or mutants. The mutants were divided into two non-permissive classes dependent on their biochemical expression in PK-15 cells: the ‘early’ class which failed to replicate virus DNA and synthesized only the ‘early’ polypeptides and the ‘late’ class which appeared to be normal both in virus DNA and polypeptide synthesis. There was no correlation between the extent of the left-hand terminal deletion and the extent of permissiveness of the mutants in PK-15 cells.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error