Phospho-accepting proteins in bovine sera.

Phospho-accepting proteins in bovine sera have been detected by the use of immobilized protein kinase from rat muscle and (gamma32P)-ATP in an in vitro system. A partial biochemical characterization points to the generation of typical phosphoproteins. Differences in the phosphorylation pattern between fetal serum and calf serum as demonstrated by electrophoresis in the presence of dodecylsulfate are described.