Isolation and immunological properties of adenosine kinase

Bovine liver adenosine kinase is a 43 kDa protein that catalyzes the transfer of phosphate from GTP or ATP to adenosine. Its immunological properties were compared to other GTP-binding proteins of approximately 40 kDa, in particular those involved in signal transduction, such as Gs and Gi, the stimulatory and inhibitory regulatory proteins of adenylyl cyclase, Gt, from the visual excitation system, and Go, a similar protein of unknown function. Antibodies elicited in rabbits against adenosine kinase did not significantly cross-react with other guanyl nucleotide-binding proteins. Antibodies against the other GTP-binding proteins did not react with adenosine kinase. Thus these GTP-binding proteins do not exhibit immunological cross-reactivity.