Jayendran Rasaiah - Academia.edu (original) (raw)
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Papers by Jayendran Rasaiah
Journal of Chemical Physics, Apr 1, 1990
Journal of Chemical Physics, Dec 1, 1992
Bulletin of the American Physical Society, Mar 16, 2010
Journal of Physical Chemistry C, Jul 16, 2020
Water-mediated interactions (WMIs) play diverse roles in molecular biology. They are particularly... more Water-mediated interactions (WMIs) play diverse roles in molecular biology. They are particularly relevant in geometrically confined spaces such as the interior of the chaperonin, at the interface between ligands and their binding partners, and in the ribosome tunnel. Inspired in part by the geometry of the ribosome tunnel, we consider confinement effects on the stability of peptides. We describe results from replica exchange molecular dynamics simulations of a system containing a 23-alanine or 23-serine polypeptide confined to non-polar and polar nanotubes in the gas phase and when open to a water reservoir. We quantify the effect of water in determining the preferred conformational states of these polypeptides by calculating the difference in the solvation free energy for the helix and coil states in the open nanotube in the two phases. Our simulations reveal several possibilities. We find that nanoscopic confinement preferentially stabilizes the helical state of polypeptides with...
The Journal of Physical Chemistry Letters, 2017
Water expulsion from protein cores is a key step in protein folding, but there is experimental ev... more Water expulsion from protein cores is a key step in protein folding, but there is experimental evidence for water in specific protein cavities. Calculations of the thermodynamics of transfer of bulk water into cavities, using MD simulations, have shown that filling of non-polar cavities with water is favored by dispersion forces at the walls of cavities large enough to contain a hydrogen-bonded cluster of at least three water molecules. The free energy of transfer is driven by the energy and not by the entropy. I will discuss the thermodynamics of water transfer into three different protein cavities: (a)a 4-water molecule cluster formed at high pressures in the large cavity of an L99A mutant of T4lysozyme studied previously by Collins et al (PNAS 102,16668-71 (2005)) (b) a 9-water molecule cluster formed at 92C in the largest cavity of the thermostable bacterial protein tetrabrachion predicted to dry at 110C and (c) water in the nonpolar cavity of interleukin 1-beta. The presence of...
The Journal of Physical Chemistry, 1990
The Journal of Physical Chemistry B, 2005
The Journal of Chemical Physics, 1976
The Journal of Chemical Physics, 1991
The sticky electrolyte mode for a weak unsymmetrical electrolyte is solved in the mean spherical ... more The sticky electrolyte mode for a weak unsymmetrical electrolyte is solved in the mean spherical approximation (MSA) when there are adhesive interactions between oppositely charged ions. The distribution functions at contact and the thermodynamic properties in this approximation are derived; the solutions reduce to those of corresponding symmetrical adhesive electrolyte studied by Rasaiah and Lee [J. Chem. Phys. 83, 6396 (1985)] when the sizes of the ions and the magnitudes of the charges are made the same and to those of adhesive nonelectrolytes when the charges are removed. When the stickiness is turned off the solutions of the primitive model electrolyte in the MSA are recovered.
The Journal of Chemical Physics, 1988
(13s) - 2.918 890 - 2.943 038 - 2.968178 (13s7p)/[13s2p] - 2.932 810 - 2.974135 - 2.978 528 (13s7... more (13s) - 2.918 890 - 2.943 038 - 2.968178 (13s7p)/[13s2p] - 2.932 810 - 2.974135 - 2.978 528 (13s7pld)/[ 13s2pld] - 2.933 063 - 2.977 655 - 2.978 668 H+b 3 (13s) - 1.280604 - 1.311 589 - 1.324986 (13s3p)/[ IOs1p] - 1.300052 - 1.336955 - 1.343357 (13s3p)/[10s2p] - 1.300052 -1.340628 - 1.343500
The Journal of Chemical Physics, 1990
The Journal of Chemical Physics, 1988
The Journal of Chemical Physics, 1992
The Journal of Chemical Physics, 1992
The general solutions obtained earlier [J. Chem. Phys. 95, 3325 (1991)] for the coupled diffusion... more The general solutions obtained earlier [J. Chem. Phys. 95, 3325 (1991)] for the coupled diffusion-reaction equations describing reversible electron transfer reactions in Debye solvents, governed by Sumi–Marcus free energy surfaces, are extended to non-Debye solvents. These solutions, which depend on the time correlation function of the reaction coordinate Δ(t), are exact in the narrow and wide window limits for Debye and non-Debye solvents and also in the slow reaction and non-diffusion limits for Debye solvents. The general solution also predicts the behavior between these limits and can be obtained as the solution to an integral equation. An iterative method of solving this equation using an effective relaxation time is discussed. The relationship between Δ(t) and the time correlation function S(t) of Born solvation energy of the reacting intermediates is elucidated.
Journal of Chemical Physics, Apr 1, 1990
Journal of Chemical Physics, Dec 1, 1992
Bulletin of the American Physical Society, Mar 16, 2010
Journal of Physical Chemistry C, Jul 16, 2020
Water-mediated interactions (WMIs) play diverse roles in molecular biology. They are particularly... more Water-mediated interactions (WMIs) play diverse roles in molecular biology. They are particularly relevant in geometrically confined spaces such as the interior of the chaperonin, at the interface between ligands and their binding partners, and in the ribosome tunnel. Inspired in part by the geometry of the ribosome tunnel, we consider confinement effects on the stability of peptides. We describe results from replica exchange molecular dynamics simulations of a system containing a 23-alanine or 23-serine polypeptide confined to non-polar and polar nanotubes in the gas phase and when open to a water reservoir. We quantify the effect of water in determining the preferred conformational states of these polypeptides by calculating the difference in the solvation free energy for the helix and coil states in the open nanotube in the two phases. Our simulations reveal several possibilities. We find that nanoscopic confinement preferentially stabilizes the helical state of polypeptides with...
The Journal of Physical Chemistry Letters, 2017
Water expulsion from protein cores is a key step in protein folding, but there is experimental ev... more Water expulsion from protein cores is a key step in protein folding, but there is experimental evidence for water in specific protein cavities. Calculations of the thermodynamics of transfer of bulk water into cavities, using MD simulations, have shown that filling of non-polar cavities with water is favored by dispersion forces at the walls of cavities large enough to contain a hydrogen-bonded cluster of at least three water molecules. The free energy of transfer is driven by the energy and not by the entropy. I will discuss the thermodynamics of water transfer into three different protein cavities: (a)a 4-water molecule cluster formed at high pressures in the large cavity of an L99A mutant of T4lysozyme studied previously by Collins et al (PNAS 102,16668-71 (2005)) (b) a 9-water molecule cluster formed at 92C in the largest cavity of the thermostable bacterial protein tetrabrachion predicted to dry at 110C and (c) water in the nonpolar cavity of interleukin 1-beta. The presence of...
The Journal of Physical Chemistry, 1990
The Journal of Physical Chemistry B, 2005
The Journal of Chemical Physics, 1976
The Journal of Chemical Physics, 1991
The sticky electrolyte mode for a weak unsymmetrical electrolyte is solved in the mean spherical ... more The sticky electrolyte mode for a weak unsymmetrical electrolyte is solved in the mean spherical approximation (MSA) when there are adhesive interactions between oppositely charged ions. The distribution functions at contact and the thermodynamic properties in this approximation are derived; the solutions reduce to those of corresponding symmetrical adhesive electrolyte studied by Rasaiah and Lee [J. Chem. Phys. 83, 6396 (1985)] when the sizes of the ions and the magnitudes of the charges are made the same and to those of adhesive nonelectrolytes when the charges are removed. When the stickiness is turned off the solutions of the primitive model electrolyte in the MSA are recovered.
The Journal of Chemical Physics, 1988
(13s) - 2.918 890 - 2.943 038 - 2.968178 (13s7p)/[13s2p] - 2.932 810 - 2.974135 - 2.978 528 (13s7... more (13s) - 2.918 890 - 2.943 038 - 2.968178 (13s7p)/[13s2p] - 2.932 810 - 2.974135 - 2.978 528 (13s7pld)/[ 13s2pld] - 2.933 063 - 2.977 655 - 2.978 668 H+b 3 (13s) - 1.280604 - 1.311 589 - 1.324986 (13s3p)/[ IOs1p] - 1.300052 - 1.336955 - 1.343357 (13s3p)/[10s2p] - 1.300052 -1.340628 - 1.343500
The Journal of Chemical Physics, 1990
The Journal of Chemical Physics, 1988
The Journal of Chemical Physics, 1992
The Journal of Chemical Physics, 1992
The general solutions obtained earlier [J. Chem. Phys. 95, 3325 (1991)] for the coupled diffusion... more The general solutions obtained earlier [J. Chem. Phys. 95, 3325 (1991)] for the coupled diffusion-reaction equations describing reversible electron transfer reactions in Debye solvents, governed by Sumi–Marcus free energy surfaces, are extended to non-Debye solvents. These solutions, which depend on the time correlation function of the reaction coordinate Δ(t), are exact in the narrow and wide window limits for Debye and non-Debye solvents and also in the slow reaction and non-diffusion limits for Debye solvents. The general solution also predicts the behavior between these limits and can be obtained as the solution to an integral equation. An iterative method of solving this equation using an effective relaxation time is discussed. The relationship between Δ(t) and the time correlation function S(t) of Born solvation energy of the reacting intermediates is elucidated.