Open-to-closed transition in apo maltose-binding protein observed by paramagnetic NMR
- 1 October 2007
- journal article
- letter
- Published by Springer Science and Business Media LLC in Nature
- Vol. 449 (7165), 1078-1082
- https://doi.org/10.1038/nature06232
Abstract
Large-scale domain rearrangements in proteins have long been recognized to have a critical function in ligand binding and recognition, catalysis and regulation1,2,3,4,5. Crystal structures have provided a static picture of the apo (usually open) and holo usually closed) states. The general question arises as to whether the apo state exists as a single species in which the closed state is energetically inaccessible and interdomain rearrangement is induced by ligand or substrate binding, or whether the predominantly open form already coexists in rapid equilibrium with a minor closed species. The maltose-binding protein (MBP), a member of the bacterial periplasmic binding protein family6, provides a model system for investigating this problem because it has been the subject of extensive studies by crystallography7,8, NMR9,10,11 and other biophysical techniques11,12,13. Here we show that although paramagnetic relaxation enhancement (PRE) data for the sugar-bound form are consistent with the crystal structure of holo MBP, the PRE data for the apo state are indicative of a rapidly exchanging mixture (ns to μs regime) of a predominantly ( ∼ 95%) open form (represented by the apo crystal structure) and a minor ( ∼ 5%) partially closed species. Using ensemble simulated annealing refinement against the PRE data we are able to determine a 〈r-6〉 ensemble average structure of the minor apo species and show that it is distinct from the sugar-bound state.This publication has 37 references indexed in Scilit:
- Intramolecular domain–domain association/dissociation and phosphoryl transfer in the mannitol transporter of Escherichia coli are not coupledProceedings of the National Academy of Sciences of the United States of America, 2007
- Practical aspects of 1H transverse paramagnetic relaxation enhancement measurements on macromoleculesJournal of Magnetic Resonance, 2006
- Structural Evidence for a Dominant Role of Nonpolar Interactions in the Binding of a Transport/Chemosensory Receptor to Its Highly Polar Ligands,Biochemistry, 2001
- Electrostatics of nanosystems: Application to microtubules and the ribosomeProceedings of the National Academy of Sciences of the United States of America, 2001
- Ligand-induced structural changes to maltodextrin-binding protein as studied by solution NMR spectroscopyJournal of Molecular Biology, 2001
- Orienting domains in proteins using dipolar couplings measured by liquid-state NMR: differences in solution and crystal forms of maltodextrin binding protein loaded with β-cyclodextrinJournal of Molecular Biology, 2000
- TROSY Triple-Resonance Four-Dimensional NMR Spectroscopy of a 46 ns Tumbling ProteinJournal of the American Chemical Society, 1999
- Measurement of Residual Dipolar Couplings of Macromolecules Aligned in the Nematic Phase of a Colloidal Suspension of Rod-Shaped VirusesJournal of the American Chemical Society, 1998
- Thermodynamic Characterization of the Reversible, Two-State Unfolding of Maltose Binding Protein, a Large Two-Domain ProteinBiochemistry, 1997
- CRYSOL– a Program to Evaluate X-ray Solution Scattering of Biological Macromolecules from Atomic CoordinatesJournal of Applied Crystallography, 1995