title: 1H NMR studies of mastoparan binding by calmodulin.
abstract: Association with the cytoactive tetradecapeptide mastoparan perturbs the downfield 1H NMR spectrum of the calmodulin-Ca42+ complex. Changes occur in the resonances assigned to His-107 and Tyr-138. Composite peaks assigned to Phe-16 and Phe-89 and to Phe-68 and Tyr-99 are also affected. Both the upfield and downfield 1H NMR spectra contain evidence for spectroscopically distinct intermediates in Ca2+ binding by the calmodulin-mastoparan complex.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001514:Bee Venoms / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002147:Calmodulin / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides; D011485:Protein Binding; D013552:Swine; D014862:Wasp Venoms / Q000378:metabolism*
chemical_list: D001514:Bee Venoms; D002147:Calmodulin; D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D014862:Wasp Venoms; C037500:mastoparan; D002118:Calcium