<unk><unk><unk>  kinases (EC 2.7.11.1) phosphorylate the OH group of<unk>  or<unk>  (which have similar sidechains).
Serine/threonine-specific protein kinase
Receptor tyrosine kinase
GTPase activating protein
Adenylate cyclase
Guanine nucleotide exchange factor
Cyclin-dependent kinase
Adenylate kinase
Magnesium transporters