title: Structure of the calcium regulatory muscle protein troponin-C at 2.8 A resolution.
abstract: Crystals of turkey skeletal muscle troponin-C reveal a molecule of two domains with an unusual structure. Two Ca2+ ions are bound to the C-terminal domain. The two cation-binding sites of the regulatory (N-terminal) domain are Ca2+ free; this domain adopts a markedly different conformation from the C-terminal domain. The two domains are connected by a long nine-turn alpha-helix; three of these turns are exposed fully to solvent.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D003461:Crystallography; D008274:Magnesium / Q000378:metabolism; D008958:Models, Molecular; D011487:Protein Conformation; D014336:Troponin / Q000378:metabolism; D014422:Turkeys; D014961:X-Ray Diffraction
chemical_list: D014336:Troponin; D008274:Magnesium; D002118:Calcium