title: Calmodulin activates prokaryotic adenylate cyclase.
abstract: The adenylate cyclase of Bordetella pertussis is stimulated 100- to 1000-fold in a dose-dependent manner by calf brain calmodulin. The system has the following properties. (i) The activation is prevented by ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid and restored by Ca2+. (ii) Oxidation of the methionine residues of calmodulin abolishes the ability to activate the cyclase. (iii) Trifluoperazine inhibits calmodulin-activated cyclase. (iv) A troponin C preparation stimulates the B. pertussis cyclase with < 0.01 the potency of calmodulin. Although calmodulin has not been demonstrated in prokaryotes, this is an example of a (eukaryotic) calmodulin effect in a prokaryote.
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism*; D001886:Bordetella pertussis / Q000201:enzymology*; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000494:pharmacology*; D002147:Calmodulin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004533:Egtazic Acid / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D014336:Troponin / Q000494:pharmacology
chemical_list: D002135:Calcium-Binding Proteins; D002147:Calmodulin; D014336:Troponin; D004533:Egtazic Acid; D000262:Adenylyl Cyclases; D002118:Calcium