1
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Shin S, Willard AP. Quantifying the Molecular Polarization Response of Liquid Water Interfaces at Heterogeneously Charged Surfaces. J Chem Theory Comput 2023; 19:1843-1852. [PMID: 36866865 DOI: 10.1021/acs.jctc.2c01256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
The hydration shells of proteins mediate interactions, such as small molecule binding, that are vital to their biological function or in some cases their dysfunction. However, even when the structure of a protein is known, the properties of its hydration environment cannot be easily predicted due to the complex interplay between protein surface heterogeneity and the collective structure of water's hydrogen bonding network. This manuscript presents a theoretical study of the influence of surface charge heterogeneity on the polarization response of the liquid water interface. We focus our attention on classical point charge models of water, where the polarization response is limited to molecular reorientation. We introduce a new computational method for analyzing simulation data that is capable of quantifying water's collective polarization response and determining the effective surface charge distribution of hydrated surfaces over atomistic length scales. To illustrate the utility of this method, we present the results of molecular dynamics simulations of liquid water in contact with a heterogeneous model surface and the CheY protein.
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Affiliation(s)
- Sucheol Shin
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.,Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Adam P Willard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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2
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Gao A, Remsing RC, Weeks JD. Local Molecular Field Theory for Coulomb Interactions in Aqueous Solutions. J Phys Chem B 2023; 127:809-821. [PMID: 36669139 DOI: 10.1021/acs.jpcb.2c06988] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Coulomb interactions play a crucial role in a wide array of processes in aqueous solutions but present conceptual and computational challenges to both theory and simulations. We review recent developments in an approach addressing these challenges─local molecular field (LMF) theory. LMF theory exploits an exact and physically suggestive separation of intermolecular Coulomb interactions into strong short-range and uniformly slowly varying long-range components. This allows us to accurately determine the averaged effects of the long-range components on the short-range structure using effective single particle fields and analytical corrections, greatly reducing the need for complex lattice summation techniques used in most standard approaches. The simplest use of these ideas in aqueous solutions leads to the short solvent (SS) model, where both solvent-solvent and solute-solvent Coulomb interactions have only short-range components. Here we use the SS model to give a simple description of pairing of nucleobases and biologically relevant ions in water.
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Affiliation(s)
- Ang Gao
- Department of Physics, Beijing University of Posts and Telecommunications, Beijing, China 100876
| | - Richard C Remsing
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - John D Weeks
- Institute for Physical Science and Technology and Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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3
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Experimental measurement, thermodynamic analysis and molecular simulation of topiramate solubility in fourteen mono-solvents at various temperatures. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116992] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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4
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Ion-dependent protein-surface interactions from intrinsic solvent response. Proc Natl Acad Sci U S A 2021; 118:2025121118. [PMID: 34172582 DOI: 10.1073/pnas.2025121118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The phyllosilicate mineral muscovite mica is widely used as a surface template for the patterning of macromolecules, yet a molecular understanding of its surface chemistry under varying solution conditions, required to predict and control the self-assembly of adsorbed species, is lacking. We utilize all-atom molecular dynamics simulations in conjunction with an electrostatic analysis based in local molecular field theory that affords a clean separation of long-range and short-range electrostatics. Using water polarization response as a measure of the electric fields that arise from patterned, surface-bound ions that direct the adsorption of charged macromolecules, we apply a Landau theory of forces induced by asymmetrically polarized surfaces to compute protein-surface interactions for two muscovite-binding proteins (DHR10-mica6 and C98RhuA). Comparison of the pressure between surface and protein in high-concentration KCl and NaCl aqueous solutions reveals ion-specific differences in far-field protein-surface interactions, neatly capturing the ability of ions to modulate the surface charge of muscovite that in turn selectively attracts one binding face of each protein over all others.
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5
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Baer MD, Shanklin J, Raugei S. Atomistic insight on structure and dynamics of spinach acyl carrier protein with substrate length. Biophys J 2021; 120:3841-3853. [PMID: 33631202 PMCID: PMC8456182 DOI: 10.1016/j.bpj.2020.12.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 01/02/2023] Open
Abstract
The plant acyl-acyl carrier protein (ACP) desaturases are a family of soluble enzymes that convert saturated fatty acyl-ACPs into their cis-monounsaturated equivalents in an oxygen-dependent reaction. These enzymes play a key role in biosynthesis of monounsaturated fatty acids in plants. ACPs are central proteins in fatty acid biosynthesis that deliver acyl chains to desaturases. They have been reported to show a varying degree of local dynamics and structural variability depending on the acyl chain size. It has been suggested that substrate-specific changes in ACP structure and dynamics have a crucial impact on the desaturase enzymatic activity. Using molecular dynamics simulations, we investigated the intrinsic solution structure and dynamics of ACP from spinach with four different acyl chains: capric (C10), myristic (C14), palmitic (C16), and stearic (C18) acids. We found that the fatty acids can adopt two distinct structural binding motifs, which feature different binding free energies and influence the ACP dynamics in a different manner. Docking simulations of ACP to castor Δ9-desaturase and ivy Δ4-desaturase suggest that ACP desaturase interactions could lead to a preferential selection between the motifs.
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Affiliation(s)
- Marcel D Baer
- Pacific Northwest National Laboratory, Physical and Computational Sciences Directorate, Richland, Washington.
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, New York
| | - Simone Raugei
- Pacific Northwest National Laboratory, Physical and Computational Sciences Directorate, Richland, Washington
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6
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Navigating the waters of membrane design. Proc Natl Acad Sci U S A 2021; 118:2024346118. [PMID: 33384327 DOI: 10.1073/pnas.2024346118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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7
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Kelkar AS, Dallin BC, Van Lehn RC. Predicting Hydrophobicity by Learning Spatiotemporal Features of Interfacial Water Structure: Combining Molecular Dynamics Simulations with Convolutional Neural Networks. J Phys Chem B 2020; 124:9103-9114. [DOI: 10.1021/acs.jpcb.0c05977] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Atharva S. Kelkar
- Department of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States
| | - Bradley C. Dallin
- Department of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States
| | - Reid C. Van Lehn
- Department of Chemical and Biological Engineering, University of Wisconsin—Madison, 1415 Engineering Drive, Madison, Wisconsin 53706, United States
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8
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Gujt J, Zimmer P, Zysk F, Süß V, Felser C, Bauer M, Kühne TD. Water structure near the surface of Weyl semimetals as catalysts in photocatalytic proton reduction. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:034101. [PMID: 32478126 PMCID: PMC7228780 DOI: 10.1063/4.0000008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 04/22/2020] [Indexed: 06/11/2023]
Abstract
In this work, second-generation Car-Parrinello-based mixed quantum-classical mechanics molecular dynamics simulations of small nanoparticles of NbP, NbAs, TaAs, and 1T-TaS2 in water are presented. The first three materials are topological Weyl semimetals, which were recently discovered to be active catalysts in photocatalytic water splitting. The aim of this research was to correlate potential differences in the water structure in the vicinity of the nanoparticle surface with the photocatalytic activity of these materials in light induced proton reduction. The results presented herein allow explaining the catalytic activity of these Weyl semimetals: the most active material, NbP, exhibits a particularly low water coordination near the surface of the nanoparticle, whereas for 1T-TaS2, with the lowest catalytic activity, the water structure at the surface is most ordered. In addition, the photocatalytic activity of several organic and metalorganic photosensitizers in the hydrogen evolution reaction was experimentally investigated with NbP as the proton reduction catalyst. Unexpectedly, the charge of the photosensitizer plays a decisive role for the photocatalytic performance.
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Affiliation(s)
- Jure Gujt
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Paderborn University, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Peter Zimmer
- Department of Chemistry, Paderborn University, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Frederik Zysk
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Paderborn University, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Vicky Süß
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - Claudia Felser
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - Matthias Bauer
- Department of Chemistry, Paderborn University, Warburger Str. 100, D-33098 Paderborn, Germany
| | - Thomas D. Kühne
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Paderborn University, Warburger Str. 100, D-33098 Paderborn, Germany
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9
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Monroe J, Barry M, DeStefano A, Aydogan Gokturk P, Jiao S, Robinson-Brown D, Webber T, Crumlin EJ, Han S, Shell MS. Water Structure and Properties at Hydrophilic and Hydrophobic Surfaces. Annu Rev Chem Biomol Eng 2020; 11:523-557. [PMID: 32169001 DOI: 10.1146/annurev-chembioeng-120919-114657] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The properties of water on both molecular and macroscopic surfaces critically influence a wide range of physical behaviors, with applications spanning from membrane science to catalysis to protein engineering. Yet, our current understanding of water interfacing molecular and material surfaces is incomplete, in part because measurement of water structure and molecular-scale properties challenges even the most advanced experimental characterization techniques and computational approaches. This review highlights progress in the ongoing development of tools working to answer fundamental questions on the principles that govern the interactions between water and surfaces. One outstanding and critical question is what universal molecular signatures capture the hydrophobicity of different surfaces in an operationally meaningful way, since traditional macroscopic hydrophobicity measures like contact angles fail to capture even basic properties of molecular or extended surfaces with any heterogeneity at the nanometer length scale. Resolving this grand challenge will require close interactions between state-of-the-art experiments, simulations, and theory, spanning research groups and using agreed-upon model systems, to synthesize an integrated knowledge of solvation water structure, dynamics, and thermodynamics.
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Affiliation(s)
- Jacob Monroe
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Mikayla Barry
- Department of Materials, University of California, Santa Barbara, California 93106, USA
| | - Audra DeStefano
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Pinar Aydogan Gokturk
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Sally Jiao
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Dennis Robinson-Brown
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Thomas Webber
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Ethan J Crumlin
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA; .,Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
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10
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Abstract
Coulomb interactions play a major role in determining the thermodynamics, structure, and dynamics of condensed-phase systems, but often present significant challenges. Computer simulations usually use periodic boundary conditions to minimize corrections from finite cell boundaries but the long range of the Coulomb interactions generates significant contributions from distant periodic images of the simulation cell, usually calculated by Ewald sum techniques. This can add significant overhead to computer simulations and hampers the development of intuitive local pictures and simple analytic theory. In this paper, we present a general framework based on local molecular field theory to accurately determine the contributions from long-ranged Coulomb interactions to the potential of mean force between ionic or apolar hydrophobic solutes in dilute aqueous solutions described by standard classical point charge water models. The simplest approximation leads to a short solvent (SS) model, with truncated solvent-solvent and solute-solvent Coulomb interactions and long-ranged but screened Coulomb interactions only between charged solutes. The SS model accurately describes the interplay between strong short-ranged solute core interactions, local hydrogen-bond configurations, and long-ranged dielectric screening of distant charges, competing effects that are difficult to capture in standard implicit solvent models.
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11
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Singh G, Sharma M, Vaish R. Tunable surface adsorption and wettability of candle soot coated on ferroelectric ceramics. J Adv Res 2019; 16:35-42. [PMID: 30899587 PMCID: PMC6412814 DOI: 10.1016/j.jare.2018.12.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/01/2018] [Accepted: 12/18/2018] [Indexed: 01/17/2023] Open
Abstract
A ferroelectric Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCZTO) ceramic was prepared using a solid-state reaction route. A coating of candle soot was provided on poled and unpoled BCZTO samples. X-ray diffraction and Raman spectroscopy confirmed the presence of the graphite form of carbon in the candle soot. Scanning Kelvin probe microscopy determined that the highest surface potentials were ∼34 mV and 1.5 V in the unpoled and poled BCZTO samples, respectively. The candle soot was found to adsorb ∼65%, 80%, and 90% of the methylene blue dye present in acidic, neutral, and basic media, respectively, within 3 h. In both the poled and unpoled cases, the BCZTO samples coated with candle soot showed greater adsorption capacities than the uncoated BCZTO sample. In the cases of poled samples coated with candle soot, the adsorption was found to be greater in the case of candle soot coated on a positively charged surface than that for candle soot coated on a negatively charged BCZTO surface in an acidic medium. In a basic medium, the adsorption was found to be greater in the case of candle soot coated on a negatively charged surface than that for candle soot coated on a positively charged BCZTO surface. The contact angle of the candle soot-coated BCZTO sample was found to be hydrophobic (∼149°). The contact angle decreased (∼149-133°) with an increase in temperature (30-70 °C) in the case of candle soot coated on the positive surface of a poled BCZTO sample. The contact angle increased (∼139-149°) with an increase in temperature (30-70 °C) in the case of candle soot coated on the negative surface of a poled BCZTO sample. Internal electric field-assisted (associated with ferroelectric materials) adsorption could be a potential technique to improve adsorption processes.
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Affiliation(s)
| | | | - Rahul Vaish
- School of Engineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh 175005, India
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12
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Computational discovery of chemically patterned surfaces that effect unique hydration water dynamics. Proc Natl Acad Sci U S A 2018; 115:8093-8098. [PMID: 30038028 DOI: 10.1073/pnas.1807208115] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The interactions of water with solid surfaces govern their apparent hydrophobicity/hydrophilicity, influenced at the molecular scale by surface coverage of chemical groups of varied nonpolar/polar character. Recently, it has become clear that the precise patterning of surface groups, and not simply average surface coverage, has a significant impact on the structure and thermodynamics of hydration layer water, and, in turn, on macroscopic interfacial properties. Here we show that patterning also controls the dynamics of hydration water, a behavior frequently thought to be leveraged by biomolecules to influence functional dynamics, but yet to be generalized. To uncover the role of surface heterogeneities, we couple a genetic algorithm to iterative molecular dynamics simulations to design the patterning of surface functional groups, at fixed coverage, to either minimize or maximize proximal water diffusivity. Optimized surface configurations reveal that clustering of hydrophilic groups increases hydration water mobility, while dispersing them decreases it, but only if hydrophilic moieties interact with water through directional, hydrogen-bonding interactions. Remarkably, we find that, across different surfaces, coverages, and patterns, both the chemical potential for inserting a methane-sized hydrophobe near the interface and, in particular, the hydration water orientational entropy serve as strong predictors for hydration water diffusivity, suggesting that these simple thermodynamic quantities encode the way surfaces control water dynamics. These results suggest a deep and intriguing connection between hydration water thermodynamics and dynamics, demonstrating that subnanometer chemical surface patterning is an important design parameter for engineering solid-water interfaces with applications spanning separations to catalysis.
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13
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Remsing RC, Xi E, Patel AJ. Protein Hydration Thermodynamics: The Influence of Flexibility and Salt on Hydrophobin II Hydration. J Phys Chem B 2018; 122:3635-3646. [DOI: 10.1021/acs.jpcb.7b12060] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Richard C. Remsing
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Erte Xi
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Amish J. Patel
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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14
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Remsing RC, Duignan TT, Baer MD, Schenter GK, Mundy CJ, Weeks JD. Water Lone Pair Delocalization in Classical and Quantum Descriptions of the Hydration of Model Ions. J Phys Chem B 2018; 122:3519-3527. [DOI: 10.1021/acs.jpcb.7b10722] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Richard C. Remsing
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Timothy T. Duignan
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington, United States
| | - Marcel D. Baer
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington, United States
| | - Gregory K. Schenter
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington, United States
| | - Christopher J. Mundy
- Chemical and Materials Science Division, Pacific Northwest National Laboratory, Richland, Washington, United States
- Affiliate Professor, Department of Chemical Engineering, University of Washington, Seattle, Washington, United States
| | - John D. Weeks
- Institute for Physical Science and Technology and Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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15
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Shin S, Willard AP. Characterizing Hydration Properties Based on the Orientational Structure of Interfacial Water Molecules. J Chem Theory Comput 2018; 14:461-465. [PMID: 29266930 DOI: 10.1021/acs.jctc.7b00898] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, we present a general computational method for characterizing the molecular structure of liquid water interfaces as sampled from atomistic simulations. With this method, the interfacial structure is quantified based on the statistical analysis of the orientational configurations of interfacial water molecules. The method can be applied to generate position dependent maps of the hydration properties of heterogeneous surfaces. We present an application to the characterization of surface hydrophobicity, which we use to analyze simulations of a hydrated protein. We demonstrate that this approach is capable of revealing microscopic details of the collective dynamics of a protein hydration shell.
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Affiliation(s)
- Sucheol Shin
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Adam P Willard
- Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
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16
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Stock P, Monroe JI, Utzig T, Smith DJ, Shell MS, Valtiner M. Unraveling Hydrophobic Interactions at the Molecular Scale Using Force Spectroscopy and Molecular Dynamics Simulations. ACS NANO 2017; 11:2586-2597. [PMID: 28267918 DOI: 10.1021/acsnano.6b06360] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Interactions between hydrophobic moieties steer ubiquitous processes in aqueous media, including the self-organization of biologic matter. Recent decades have seen tremendous progress in understanding these for macroscopic hydrophobic interfaces. Yet, it is still a challenge to experimentally measure hydrophobic interactions (HIs) at the single-molecule scale and thus to compare with theory. Here, we present a combined experimental-simulation approach to directly measure and quantify the sequence dependence and additivity of HIs in peptide systems at the single-molecule scale. We combine dynamic single-molecule force spectroscopy on model peptides with fully atomistic, both equilibrium and nonequilibrium, molecular dynamics (MD) simulations of the same systems. Specifically, we mutate a flexible (GS)5 peptide scaffold with increasing numbers of hydrophobic leucine monomers and measure the peptides' desorption from hydrophobic self-assembled monolayer surfaces. Based on the analysis of nonequilibrium work-trajectories, we measure an interaction free energy that scales linearly with 3.0-3.4 kBT per leucine. In good agreement, simulations indicate a similar trend with 2.1 kBT per leucine, while also providing a detailed molecular view into HIs. This approach potentially provides a roadmap for directly extracting qualitative and quantitative single-molecule interactions at solid/liquid interfaces in a wide range of fields, including interactions at biointerfaces and adhesive interactions in industrial applications.
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Affiliation(s)
- Philipp Stock
- Department for Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH , D-40237 Düsseldorf, Germany
| | - Jacob I Monroe
- Department of Chemical Engineering, University of California Santa Barbara , Santa Barbara, California 93106-5080, United States
| | - Thomas Utzig
- Department for Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH , D-40237 Düsseldorf, Germany
| | - David J Smith
- Department of Chemical Engineering, University of California Santa Barbara , Santa Barbara, California 93106-5080, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California Santa Barbara , Santa Barbara, California 93106-5080, United States
| | - Markus Valtiner
- Department for Interface Chemistry and Surface Engineering, Max-Planck-Institut für Eisenforschung GmbH , D-40237 Düsseldorf, Germany
- Department for Physical Chemistry, Technische Universität Bergakademie Freiberg , D-09599 Freiberg, Germany
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17
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Remsing RC, Weeks JD. Role of Local Response in Ion Solvation: Born Theory and Beyond. J Phys Chem B 2016; 120:6238-49. [DOI: 10.1021/acs.jpcb.6b02238] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Richard C. Remsing
- Institute
for Computational Molecular Science and Center for the Computational
Design of Functional Layered Materials, Temple University, Philadelphia, Pennsylvania 19122, United States
- Institute
for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, United States
| | - John D. Weeks
- Institute
for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, United States
- Department
of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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18
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Shi B, Agnihotri MV, Chen SH, Black R, Singer SJ. Polarization charge: Theory and applications to aqueous interfaces. J Chem Phys 2016; 144:164702. [DOI: 10.1063/1.4945760] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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19
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Remsing RC, Liu S, Weeks JD. Long-ranged contributions to solvation free energies from theory and short-ranged models. Proc Natl Acad Sci U S A 2016; 113:2819-26. [PMID: 26929375 PMCID: PMC4801310 DOI: 10.1073/pnas.1521570113] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Long-standing problems associated with long-ranged electrostatic interactions have plagued theory and simulation alike. Traditional lattice sum (Ewald-like) treatments of Coulomb interactions add significant overhead to computer simulations and can produce artifacts from spurious interactions between simulation cell images. These subtle issues become particularly apparent when estimating thermodynamic quantities, such as free energies of solvation in charged and polar systems, to which long-ranged Coulomb interactions typically make a large contribution. In this paper, we develop a framework for determining very accurate solvation free energies of systems with long-ranged interactions from models that interact with purely short-ranged potentials. Our approach is generally applicable and can be combined with existing computational and theoretical techniques for estimating solvation thermodynamics. We demonstrate the utility of our approach by examining the hydration thermodynamics of hydrophobic and ionic solutes and the solvation of a large, highly charged colloid that exhibits overcharging, a complex nonlinear electrostatic phenomenon whereby counterions from the solvent effectively overscreen and locally invert the integrated charge of the solvated object.
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Affiliation(s)
- Richard C Remsing
- Institute for Physical Science and Technology and Chemical Physics Program, University of Maryland, College Park, MD 20742; Institute for Computational Molecular Science, Temple University, Philadelphia, PA 19122
| | - Shule Liu
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742; Department of Chemistry, James Franck Institute and Computation Institute, University of Chicago, Chicago, IL 60637
| | - John D Weeks
- Institute for Physical Science and Technology and Chemical Physics Program, University of Maryland, College Park, MD 20742; Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742;
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