Vibrational softening of a protein on ligand binding.

Neutron scattering experiments have demonstrated that binding of the cancer drug methotrexate softens the low-frequency vibrations of its target protein, dihydrofolate reductase (DHFR). Here, this softening is fully reproduced using atomic detail normal-mode analysis. Decomposition of the vibrational density of states demonstrates that the largest contributions arise from structural elements of DHFR critical to stability and function. Mode-projection analysis reveals an increase of the breathing-like character of the affected vibrational modes consistent with the experimentally observed increased adiabatic compressibility of the protein on complexation.

[1]  Bernard R. Brooks,et al.  Inelastic neutron scattering analysis of low frequency motion in proteins: A normal mode study of the bovine pancreatic trypsin inhibitor , 1986 .

[2]  Thorpe,et al.  Coulomb effects in disordered solids. , 1986, Physical review. B, Condensed matter.

[3]  M Karplus,et al.  Polar hydrogen positions in proteins: Empirical energy placement and neutron diffraction comparison , 1988, Proteins.

[4]  Hoover,et al.  Canonical dynamics: Equilibrium phase-space distributions. , 1985, Physical review. A, General physics.

[5]  K. Gekko,et al.  Point mutations at glycine-121 of Escherichia coli dihydrofolate reductase: important roles of a flexible loop in the stability and function. , 1994, Journal of biochemistry.

[6]  Franci Merzel,et al.  Lattice dynamics of a protein crystal. , 2007, Physical review letters.

[7]  D. Fushman,et al.  Determination of the backbone mobility of ribonuclease T1 and its 2'GMP complex using molecular dynamics simulations and NMR relaxation data. , 1994, Journal of biomolecular structure & dynamics.

[8]  Effects of point mutations at the flexible loop glycine-67 of Escherichia coli dihydrofolate reductase on its stability and function. , 1996, Journal of biochemistry.

[9]  Jeremy C. Smith,et al.  Conformational heterogeneity and low-frequency vibrational modes of proteins. , 2006, Physical chemistry chemical physics : PCCP.

[10]  G. Kearley,et al.  Atomistic model of DNA: phonons and base-pair opening. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[11]  S. Nosé A molecular dynamics method for simulations in the canonical ensemble , 1984 .

[12]  Mark R. Johnson,et al.  NMscatt: a program for calculating inelastic scattering from large biomolecular systems using classical force-field simulations , 2007, Comput. Phys. Commun..

[13]  Jeremy C. Smith,et al.  Theory and normal-mode analysis of change in protein vibrational dynamics on ligand binding. , 2010, The journal of physical chemistry. B.

[14]  Laxmikant V. Kalé,et al.  Scalable molecular dynamics with NAMD , 2005, J. Comput. Chem..

[15]  C. Brooks,et al.  Protein Dynamics in Enzymatic Catalysis: Exploration of Dihydrofolate Reductase , 2000 .

[16]  J. Kraut,et al.  Loop and subdomain movements in the mechanism of Escherichia coli dihydrofolate reductase: crystallographic evidence. , 1997, Biochemistry.

[17]  M Karplus,et al.  The contribution of vibrational entropy to molecular association. The dimerization of insulin. , 1994, Journal of molecular biology.

[18]  M. Karplus,et al.  CHARMM: A program for macromolecular energy, minimization, and dynamics calculations , 1983 .

[19]  S J Oatley,et al.  Functional role of aspartic acid-27 in dihydrofolate reductase revealed by mutagenesis. , 1986, Science.

[20]  E. J. Loveridge,et al.  Solvent effects on catalysis by Escherichia coli dihydrofolate reductase. , 2010, Journal of the American Chemical Society.

[21]  W. L. Jorgensen,et al.  Comparison of simple potential functions for simulating liquid water , 1983 .

[22]  Stefan Fischer,et al.  Structure, dynamics and reactions of protein hydration water. , 2004, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[23]  K. Gekko,et al.  Effect of ligand binding on the flexibility of dihydrofolate reductase as revealed by compressibility. , 2000, Biochimica et biophysica acta.

[24]  Torsten Becker,et al.  Direct determination of vibrational density of states change on ligand binding to a protein. , 2004, Physical review letters.

[25]  J. Moore,et al.  15N NMR relaxation studies of the FK506 binding protein: dynamic effects of ligand binding and implications for calcineurin recognition. , 1994, Biochemistry.

[26]  Chandra Verma,et al.  Dissecting the Vibrational Entropy Change on Protein/Ligand Binding: Burial of a Water Molecule in Bovine Pancreatic Trypsin Inhibitor , 2001 .

[27]  P. Agarwal,et al.  Network of coupled promoting motions in enzyme catalysis , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[28]  Giovanni Dietler,et al.  Functional dynamics of PDZ binding domains: a normal-mode analysis. , 2005, Biophysical journal.

[29]  P. Wright,et al.  Dynamics of the dihydrofolate reductase-folate complex: catalytic sites and regions known to undergo conformational change exhibit diverse dynamical features. , 1995, Biochemistry.

[30]  Rino,et al.  Dynamic structure factor and vibrational properties of SiO2 glass. , 1993, Physical review. B, Condensed matter.

[31]  F. M. Huennekens,et al.  The methotrexate story: a paradigm for development of cancer chemotherapeutic agents. , 1994, Advances in enzyme regulation.

[32]  B. Brooks,et al.  Effect of Electrostatic Force Truncation on Interfacial and Transport Properties of Water , 1996 .

[33]  Alexander D. MacKerell,et al.  All-atom empirical potential for molecular modeling and dynamics studies of proteins. , 1998, The journal of physical chemistry. B.

[34]  Carol Beth Post,et al.  Decomposition of protein experimental compressibility into intrinsic and hydration shell contributions. , 2006, Biophysical journal.

[35]  Paweł T. Jochym,et al.  Atomic vibrational density of states of crystalline β-Fe Si 2 and amorphous Fe Si 2 thin films , 2005 .

[36]  Dusanka Janezic,et al.  Harmonic analysis of large systems. I. Methodology , 1995, J. Comput. Chem..