title: Location of divalent ion sites in acyl carrier protein using relaxation perturbed 2D NMR.
abstract: The T1-accordion COSY experiment has been applied to acyl carrier protein (ACP) to locate the divalent ion binding sites in the protein using the paramagnetic ion, Mn2+, as a substitute for Ca2+. Replacement with Mn2+ leads to an enhancement of proton spin-lattice (T1) relaxation rates. These enhancements have a 1/r6 distance dependence that makes them extremely useful in structural analyses. Ion-proton distances ranging from 3.0 to 9.0 A have been obtained from this experiment and subsequently used as constraints in the molecular mechanics module of AMBER to refine a protein structure.
mesh_terms: D000213:Acyl Carrier Protein / Q000378:metabolism*; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008345:Manganese / Q000378:metabolism*; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation
chemical_list: D000213:Acyl Carrier Protein; D008345:Manganese; D002118:Calcium