Protein phosphorylation in Escherichia coli and purification of a protein kinase.

摘要: More than 40 protein species including RNA polymerase were found to be phosphorylated in Escherichia coli on analyses of 32P-labeled cell lysates by single and two-dimensional gel electrophoresis autoradiography. The the level phosphorylation varied depending growth phase. With [gamma-32P]ATP as a substrate, endogenous proteins vitro which predominantly vivo. Both serine threonine major phosphate acceptors whole lysates. Starting from partially purified preparation with activity using an E. apparent Mr = 90K (K represents X 1000) we kinase native approximately 120K homogeneity. is either heterodimer 61K 66K polypeptides or homodimer one these polypeptides. We also isolated 100K self-phosphorylation activity.