Evidence for the ubiquitous presence of a protein kinase in human adenoviruses capable of preferentially phosphorylating capsid protein IIIa.

Several years ago a protein kinase activity was demonstrated in subgroup C adenoviruses. In this report we have demonstrated the presence of a similar protein kinase activity in adenoviruses of subgroups A, B, and D; like the subgroup C adenovirus kinase, it preferentially phosphorylates capsid protein IIIa. Further, we have shown that the protein kinase activity is independent of the host cell line used to grow the virus and is not inhibited by N-tosyl-L-lysine chloromethyl ketone or by N-tosyl-L-phenylalanine chloromethyl ketone (known inhibitors of other protein kinases). These results suggest that the adenovirus-associated protein kinase is an inherent component of all mature adenovirus particles, and as such may play a role in the virus life cycle.