the results provide further support for our hypothesis [ ahmed , wilson , goueli & williams-ashman ( 1978 ) biochem . j . 176 , 739-750 ] that the enhancement of certain protein kinase reactions by polycations relates primarily to their interaction with the protein substrate , yielding more favourable conformations for phosphorylation by the protein kinase , rather than a direct effect on its catalytic activity .
C0031715
phosphorylation
C0033640
protein kinase