In this work, we design and use a new biomolecular simulation technique that combines explicit solvent molecules and implicit solvent theory. We employ a multigrid approach to speed up the computationally expensive long-range electrostatic energy terms ubiquitous to the classical simulation of biomolecules. It is shown that the multigrid technique affords an order-of-magnitude speedup over conventional cutoff approaches. Our algorithm makes possible a new class of biomolecular simulations that was previously untenable (i.e., the calculation of solvation energies of entire proteins using explicit water molecules). We present comparisons of protein solvation energies obtained from our method and a popular implicit solvent model.
In this work, we design and use a new biomolecular simulation technique that combines explicit solvent molecules and implicit solvent theory. We employ a multigrid approach to speed up the computationally expensive long-range electrostatic energy terms ubiquitous to the classical simulation of biomolecules. It is shown that the multigrid technique affords an order-of-magnitude speedup over conventional cutoff approaches. Our algorithm makes possible a new class of biomolecular simulations that was previously untenable (i.e., the calculation of solvation energies of entire proteins using explicit water molecules). We present comparisons of protein solvation energies obtained from our method and a popular implicit solvent model.
We present a new hybrid explicit/implicit solvent method for dynamics simulations of macromolecular systems. The method models explicitly the hydration of the solute by either a layer or sphere of water molecules, and the generalized Born (GB) theory is used to treat the bulk continuum solvent outside the explicit simulation volume. To reduce the computational cost, we implemented a multigrid method for evaluating the pairwise electrostatic and GB terms. It is shown that for typical ion and protein simulations our method achieves similar equilibrium and dynamical observables as the conventional particle mesh Ewald (PME) method. Simulation timings are reported, which indicate that the hybrid method is much faster than PME, primarily due to a significant reduction in the number of explicit water molecules required to model hydration effects.
Models of biomolecular structure and dynamics are often obtained by combining simulation or prediction approaches (e.g., comparative modeling, Molecular Dynamics (MD) simulations, Normal Mode Analysis (NMA), etc.) with experimental approaches (e.g., Nuclear Magnetic Resonance (NMR), X-ray crystallography, Small-Angle X-ray Scattering (SAXS), Electron Microscopy (EM), etc.). Such hybrid modeling extends the capabilities of experimental techniques, by enriching structural information and facilitating dynamics studies of biomolecules. This eBook contains articles on methodological developments, applications, and challenges of hybrid biomolecular modeling that have been collected in the framework of the Frontiers Research Topic entitled “Hybrid Biomolecular Modeling”.
Implicit solvation provides a means of accelerating and improving the efficiency of computational biomolecular studies by eliminating explicit solvent degrees of freedom while still representing the effects of solvation. Evidence is provided supporting the importance of defining the implicit solvent-solute boundary such that solvent is excluded from spaces smaller than a water molecule. The pairwise analytical generalized Born (GB) model, a popular implicit solvent model, is extended to incorporate this property. Methods for conducting molecular dynamics simulations at a constant pH, rather than the traditional constant protonation state, are reviewed and a constant pH method employing a consistent GB-based Hamiltonian for conformational and protonation state sampling is developed. Even with the improved efficiency of implicit solvent, it is difficult to achieve sufficient sampling in molecular dynamics. This problem is addressed by accelerated molecular dynamics, a technique for accelerating sampling that requires no advance knowledge of the potential energy landscape is presented. Analysis of molecular dynamics data is aided by Interactive Essential Dynamics, a tool for visualization of principal component analysis results. Implicit solvent methods are applied to the computer-aided design of inhibitors for the zinc(II) proteases stromelysin-1 and anthrax lethal factor. Inhibitors with IC-50 of 100 nM and 14 micromolar are reported for stromelysin-1 and lethal factor, respectively. Use of the GB model developed here allows for accurate elucidation of the binding mode of the lethal factor inhibitor, while GB models that allow solvent in spaces smaller than a water molecule identify an incorrect binding mode.
An essential guide to biomolecular and bioanalytical techniques and their applications Biomolecular and Bioanalytical Techniques offers an introduction to, and a basic understanding of, a wide range of biophysical techniques. The text takes an interdisciplinary approach with contributions from a panel of distinguished experts. With a focus on research, the text comprehensively covers a broad selection of topics drawn from contemporary research in the fields of chemistry and biology. Each of the internationally reputed authors has contributed a single chapter on a specific technique. The chapters cover the specific technique’s background, theory, principles, technique, methodology, protocol and applications. The text explores the use of a variety of analytical tools to characterise biological samples. The contributors explain how to identify and quantify biochemically important molecules, including small molecules as well as biological macromolecules such as enzymes, antibodies, proteins, peptides and nucleic acids. This book is filled with essential knowledge and explores the skills needed to carry out the research and development roles in academic and industrial laboratories. A technique-focused book that bridges the gap between an introductory text and a book on advanced research methods Provides the necessary background and skills needed to advance the research methods Features a structured approach within each chapter Demonstrates an interdisciplinary approach that serves to develop independent thinking Written for students in chemistry, biological, medical, pharmaceutical, forensic and biophysical sciences, Biomolecular and Bioanalytical Techniques is an in-depth review of the most current biomolecular and bioanalytical techniques in the field.
The school held at Villa Marigola, Lerici, Italy, in July 1997 was very much an educational experiment aimed not just at teaching a new generation of students the latest developments in computer simulation methods and theory, but also at bringing together researchers from the condensed matter computer simulation community, the biophysical chemistry community and the quantum dynamics community to confront the shared problem: the development of methods to treat the dynamics of quantum condensed phase systems.This volume collects the lectures delivered there. Due to the focus of the school, the contributions divide along natural lines into two broad groups: (1) the most sophisticated forms of the art of computer simulation, including biased phase space sampling schemes, methods which address the multiplicity of time scales in condensed phase problems, and static equilibrium methods for treating quantum systems; (2) the contributions on quantum dynamics, including methods for mixing quantum and classical dynamics in condensed phase simulations and methods capable of treating all degrees of freedom quantum-mechanically.
The COSMO-RS technique is a novel method for predicting the thermodynamic properties of pure and mixed fluids which are important in many areas, ranging from chemical engineering to drug design. COSMO-RS, From Quantum Chemistry to Fluid Phase Thermodynamics and Drug Design is about this novel technology, which has recently proven to be the most reliable and efficient tool for the prediction of vapour-liquid equilibria. In contrast to group contribution methods, which depend on an extremely large number of experimental data, COSMO-RS calculates the thermodynamic data from molecular surface polarity distributions, resulting from quantum chemical calculations of the individual compounds in the mixture. In this book, the author cleverly combines a vivid overview of the partly demanding theoretical steps with a deeper analysis of their scientific background and justification. Aimed at theoretical chemists, computational chemists, physical chemists, chemical engineers, thermodynamicists as well as students,academic and industrial experts, COSMO-RS, From Quantum Chemistry to Fluid Phase Thermodynamics and Drug Design provides a novel viewpoint to anyone looking to gain more insight into the theory and potential of the unique method, COSMO-RS. The only book currently available on COSMO-RS technique Provides a novel viewpoint for the scientific understanding and for the practical quantitative treatment of fluid phase thermodynamics Includes illustrative examples of the COSMOtherm program
