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Galano‐Frutos JJ, Sancho J. Energy, water, and protein folding: A molecular dynamics-based quantitative inventory of molecular interactions and forces that make proteins stable. Protein Sci 2024; 33:e4905. [PMID: 38284492 PMCID: PMC10804899 DOI: 10.1002/pro.4905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 12/12/2023] [Accepted: 01/05/2024] [Indexed: 01/30/2024]
Abstract
Protein folding energetics can be determined experimentally on a case-by-case basis but it is not understood in sufficient detail to provide deep control in protein design. The fundamentals of protein stability have been outlined by calorimetry, protein engineering, and biophysical modeling, but these approaches still face great difficulty in elucidating the specific contributions of the intervening molecules and physical interactions. Recently, we have shown that the enthalpy and heat capacity changes associated to the protein folding reaction can be calculated within experimental error using molecular dynamics simulations of native protein structures and their corresponding unfolded ensembles. Analyzing in depth molecular dynamics simulations of four model proteins (CI2, barnase, SNase, and apoflavodoxin), we dissect here the energy contributions to ΔH (a key component of protein stability) made by the molecular players (polypeptide and solvent molecules) and physical interactions (electrostatic, van der Waals, and bonded) involved. Although the proteins analyzed differ in length, isoelectric point and fold class, their folding energetics is governed by the same quantitative pattern. Relative to the unfolded ensemble, the native conformations are enthalpically stabilized by comparable contributions from protein-protein and solvent-solvent interactions, and almost equally destabilized by interactions between protein and solvent molecules. The native protein surface seems to interact better with water than the unfolded one, but this is outweighed by the unfolded surface being larger. From the perspective of physical interactions, the native conformations are stabilized by van de Waals and Coulomb interactions and destabilized by conformational strain arising from bonded interactions. Also common to the four proteins, the sign of the heat capacity change is set by interactions between protein and solvent molecules or, from the alternative perspective, by Coulomb interactions.
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Affiliation(s)
- Juan José Galano‐Frutos
- Biocomputation and Complex Systems Physics Institute (BIFI)‐Joint Unit GBsC‐CSICUniversity of ZaragozaZaragozaSpain
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de CienciasUniversity of ZaragozaZaragozaSpain
| | - Javier Sancho
- Biocomputation and Complex Systems Physics Institute (BIFI)‐Joint Unit GBsC‐CSICUniversity of ZaragozaZaragozaSpain
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de CienciasUniversity of ZaragozaZaragozaSpain
- Aragon Health Research Institute (IIS Aragón)ZaragozaSpain
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2
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Trama M, Cataudella V, Perroni CA, Romeo F, Citro R. Effect of Confinement and Coulomb Interactions on the Electronic Structure of the (111) LaAlO 3/SrTiO 3 Interface. Nanomaterials (Basel) 2023; 13:819. [PMID: 36903699 PMCID: PMC10005189 DOI: 10.3390/nano13050819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
A tight binding supercell approach is used for the calculation of the electronic structure of the (111) LaAlO3/SrTiO3 interface. The confinement potential at the interface is evaluated solving a discrete Poisson equation by means of an iterative method. In addition to the effect of the confinement, local Hubbard electron-electron terms are included at the mean-field level within a fully self-consistent procedure. The calculation carefully describes how the two-dimensional electron gas arises from the quantum confinement of electrons near the interface due to the band bending potential. The resulting electronic sub-bands and Fermi surfaces show full agreement with the electronic structure determined by angle-resolved photoelectron spectroscopy experiments. In particular, we analyse how the effect of local Hubbard interactions change the density distribution over the layers from the interface to the bulk. Interestingly, the two-dimensional electron gas at the interface is not depleted by local Hubbard interactions which indeed induce an enhancement of the electron density between the first layers and the bulk.
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Affiliation(s)
- Mattia Trama
- Physics Department “E.R. Caianiello”, Universitá degli Studi di Salerno, Via Giovanni Paolo II, 132, I-84084 Fisciano, Italy
- INFN—Sezione di Napoli, Complesso Universitario Monte S. Angelo, I-80126 Naples, Italy
- Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| | - Vittorio Cataudella
- Physics Department “Ettore Pancini”, Universitá degli Studi di Napoli “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Naples, Italy
- CNR-SPIN Napoli Unit, Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Naples, Italy
| | - Carmine Antonio Perroni
- Physics Department “Ettore Pancini”, Universitá degli Studi di Napoli “Federico II”, Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Naples, Italy
- CNR-SPIN Napoli Unit, Complesso Universitario Monte S. Angelo, Via Cintia, I-80126 Naples, Italy
| | - Francesco Romeo
- Physics Department “E.R. Caianiello”, Universitá degli Studi di Salerno, Via Giovanni Paolo II, 132, I-84084 Fisciano, Italy
| | - Roberta Citro
- Physics Department “E.R. Caianiello”, Universitá degli Studi di Salerno, Via Giovanni Paolo II, 132, I-84084 Fisciano, Italy
- INFN—Sezione di Napoli, Complesso Universitario Monte S. Angelo, I-80126 Naples, Italy
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Zhang L, Zhou F, Zhang X, Yang S, Wen B, Yan H, Yildirim T, Song X, Yang Q, Tian M, Wan N, Song H, Pei J, Qin S, Zhu J, Wageh S, Al-Hartomy OA, Al-Sehemi AG, Shen H, Liu Y, Zhang H. Discovery of Type II Interlayer Trions. Adv Mater 2023; 35:e2206212. [PMID: 36373507 DOI: 10.1002/adma.202206212] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/25/2022] [Indexed: 06/16/2023]
Abstract
In terms of interlayer trions, electronic excitations in van der Waals heterostructures (vdWHs) can be classified into Type I (i.e., two identical charges in the same layer) and Type II (i.e., two identical charges in the different layers). Type I interlayer trions are investigated theoretically and experimentally. By contrast, Type II interlayer trions remain elusive in vdWHs, due to inadequate free charges, unsuitable band alignment, reduced Coulomb interactions, poor interface quality, etc. Here, the first observation of Type II interlayer trions is reported by exploring band alignments and choosing an atomically thin organic-inorganic system-monolayer WSe2 /bilayer pentacene heterostructure (1L + 2L HS). Both positive and negative Type II interlayer trions are electrically tuned and observed via PL spectroscopy. In particular, Type II interlayer trions exhibit in-plane anisotropic emission, possibly caused by their unique spatial structure and anisotropic charge interactions, which is highly correlated with the transition dipole moment of pentacene. The results pave the way to develop excitonic devices and all-optical circuits using atomically thin organic-inorganic bilayers.
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Affiliation(s)
- Linglong Zhang
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Fei Zhou
- State Key Laboratory for Environment-friendly Energy Materials, School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Xiaowei Zhang
- Department of Electrical Engineering and Computer Science, Ningbo University, Ningbo, 315211, China
| | - Shunshun Yang
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Bo Wen
- Institute of Nanosurface Science and Engineering, Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Han Yan
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK
| | - Tanju Yildirim
- Center for Functional Sensor & Actuator (CFSN), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
| | - Xiaoying Song
- College of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
| | - Qi Yang
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Ming Tian
- SEU-FEI Nano Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronics Science and Engineering, Southeast University, Nanjing, 210096, China
| | - Neng Wan
- SEU-FEI Nano Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronics Science and Engineering, Southeast University, Nanjing, 210096, China
| | - Hucheng Song
- Center of Energy Storage Materials & Technology, College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructures/Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Jiajie Pei
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian, 350108, China
| | - Shuchao Qin
- Key Laboratory of Optical Communication Science and Technology of Shandong Province, School of Physical Science and Information Engineering, Liaocheng University, Liaocheng, 252059, China
| | - Jiaqi Zhu
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - S Wageh
- Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Omar A Al-Hartomy
- Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Abdullah G Al-Sehemi
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | | | - Youwen Liu
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Han Zhang
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
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Stefański P. Sub-gap Fano resonances in a topological superconducting wire with on-site Coulomb interactions. J Phys Condens Matter 2021; 33:465602. [PMID: 34388745 DOI: 10.1088/1361-648x/ac1d6d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
We consider theoretically a 1D-semiconducting wire with strong Rashba interaction in proximity withs-wave superconductor, driven into topological phase by external magnetic field. Additionally, we take into account on-site Coulomb interactions inside the wire. The system is modelled by a tight binding Hamiltonian with Rashba hopping term and induceds-wave superconductivity. Calculations are performed utilizing recursive Green's function method, and Coulomb interactions are treated selfconsistently within Hubbard I approximation. For the Hubbard levels residing withinp-wave superconducting gap, particle-hole symmetric four-resonance structure develops in the density of states, apart from Majorana resonance. One pair of particle-hole symmetric resonances is created by the discrete II-Hubbard levels of the particular site, and the second pair of Hubbard sub-bands originates from recursive summation over the sites of the wire. Quantum interference between both types of pairs of states creates in-gap charge-conjugated Fano resonances with opposite asymmetry factors. We demonstrate that when quantum interference is dominated by two-particle tunneling, the Majorana resonance is strongly diminished, while it is not altered when single-particle tunneling dominates in interference process. We also discuss some consequences for experimental distinction of true Majorana states, and show that on-site Coulomb interactions support the appearance of topological phase.
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Affiliation(s)
- Piotr Stefański
- Institute of Molecular Physics of the Polish Academy of Sciences, ul. Smoluchowskiego 17, 60-179 Poznań, Poland
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Stopka J, Zuidema W, Kruit P. Trajectory displacement in a multi beam scanning electron microscope. Ultramicroscopy 2021; 223:113223. [PMID: 33556712 DOI: 10.1016/j.ultramic.2021.113223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 11/23/2022]
Abstract
The analytical theory of statistical Coulomb interactions allows to determine the trajectory displacement in a single rotationally symmetrical beam with well-behaved spatial and angular particle distributions. This can be used to estimate the trajectory displacement in a multi-beam system using the so called fully-filled segment approximation. This approach predicts full compensation of trajectory displacement for a specific setup of the system. We show that this prediction is not consistent with Monte Carlo simulations and we develop a new approach to the calculation, showing that two independent trajectory displacement contributions are present in a multi-beam system. We support this calculation with Monte Carlo simulations as well as with experimental data from a multi-beam system.
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Mohapatra S, Singh A. Magnetic reorientation transition in a three orbital model for Ca 2RuO 4-interplay of spin-orbit coupling, tetragonal distortion, and Coulomb interactions. J Phys Condens Matter 2020; 32:485805. [PMID: 32759475 DOI: 10.1088/1361-648x/abacad] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/05/2020] [Indexed: 06/11/2023]
Abstract
Including the orbital off-diagonal spin and charge condensates in the self consistent determination of magnetic order within a realistic three-orbital model for the 4d4compound Ca2RuO4, reveals a host of novel features including strong and anisotropic spin-orbit coupling (SOC) renormalization, coupling of strong orbital magnetic moments to orbital fields, and a magnetic reorientation transition. Highlighting the rich interplay between orbital geometry and overlap, SOC, Coulomb interactions, tetragonal distortion, and staggered octahedral tilting and rotation, our investigation yields a planar antiferromagnetic (AFM) order for moderate tetragonal distortion, with easya-bplane and easybaxis anisotropies, along with small canting of the dominantlyyz,xzorbital moments. With decreasing tetragonal distortion, we find a magnetic reorientation transition from the dominantly planar AFM order to a dominantlycaxis ferromagnetic order with significantxyorbital moment.
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Affiliation(s)
| | - Avinash Singh
- Department of Physics, Indian Institute of Technology, Kanpur - 208016, India
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Zimbovskaya NA. Charge and heat current rectification by a double-dot system within the Coulomb blockade regime. J Phys Condens Matter 2020; 32:325302. [PMID: 32217812 DOI: 10.1088/1361-648x/ab83e9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 03/26/2020] [Indexed: 06/10/2023]
Abstract
Nanoscale rectifiers are known to have significant nanoelectronic and nanoheatronic applications. In the present work we theoretically analyze rectifying properties of a junction including a couple of quantum dots asymmetrically coupled to the electrodes. The charge and heat current rectification in the system is controlled by the dots occupation numbers and interdot Coulomb interactions. We examine the dependencies of the rectification ratio on the electron energy levels on the dots, on the intensity of electron-electron interactions, on the gate and bias voltages and on the thermal gradients applied across the system. It is shown that the considered double-dot system possesses significant potentialities as a common as well as a heat diode.
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Affiliation(s)
- Natalya A Zimbovskaya
- Department of Physics and Electronics, University of Puerto Rico-Humacao, CUH Station, Humacao, PR 00791, United States of America
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8
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Qin Y, Wang Y, Sun X, Li Y, Xu H, Tan Y, Li Y, Song T, Sun B. Constant Electricity Generation in Nanostructured Silicon by Evaporation-Driven Water Flow. Angew Chem Int Ed Engl 2020; 59:10619-10625. [PMID: 32187779 DOI: 10.1002/anie.202002762] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/17/2020] [Indexed: 11/12/2022]
Abstract
Recently, hydrovoltaic technology emerged as a novel renewable energy harvesting method, which dramatically extends the capability to harvest water energy. However, the urgent issue restricting its device performance is poor carrier transport properties of the solid surface if large charged interface is considered simultaneously. Herein, a hydrovoltaic device based on silicon nanowire arrays (SiNWs), which provide large charged surface/volume ratio and excellent carrier transport properties, yields sustained electricity by a carrier concentration gradient induced by evaporation-induced water flow inside nanochannels. The device can yield direct current with a short-circuit current density of over 55 μA cm-2 , which is three orders larger than a previously reported analogous device (approximately 40 nA cm-2 ). Moreover, it exhibits a constant output power density of over 6 μW cm-2 and an open-circuit voltage of up to 400 mV. Our finding may pave a way for developing energy-harvesting devices from ubiquitous evaporation-driven internal water flow in nature with semiconductor material of silicon.
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Affiliation(s)
- Yuanshuai Qin
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Yusheng Wang
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Xiaoyue Sun
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Yajuan Li
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Hao Xu
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Yeshu Tan
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Ya Li
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Tao Song
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
| | - Baoquan Sun
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, 215123, P. R. China
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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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Shahnazaryan V, Mughnetsyan V, Shelykh I, Sarkisyan H. Exciton-Exciton Interactions in Coaxial Double Quantum Rings. Nanomaterials (Basel) 2019; 9:nano9101469. [PMID: 31623195 PMCID: PMC6836289 DOI: 10.3390/nano9101469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/07/2019] [Accepted: 10/13/2019] [Indexed: 11/16/2022]
Abstract
We study theoretically the quantum states of two interacting excitons in coaxial double quantum rings. An interplay between exciton–exciton Coulomb interactions and specific geometry of the structure leads to the emergence of peculiar energy spectrum of two exciton system. We develop a semi-analytic approach providing highly accurate energies of system in the wide range of values of geometrical parameters relevant to experimental realizations.
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Affiliation(s)
- Vanik Shahnazaryan
- Faculty of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
| | - Vram Mughnetsyan
- Faculty of Physics, Yerevan State University, Yerevan 0025, Armenia.
| | - Ivan Shelykh
- Faculty of Physics and Engineering, ITMO University, 197101 St. Petersburg, Russia.
- Science Institute, University of Iceland, IS-107 Reykjavik, Iceland.
| | - Hayk Sarkisyan
- Faculty of Physics, Yerevan State University, Yerevan 0025, Armenia.
- Institute of Engineering and Physics, Russian-Armenian (Slavonic) University, Yerevan 0026, Armenia.
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Rath P, Sharpe T, Hiller S. The electrostatic core of the outer membrane protein X from E. coli. Biochim Biophys Acta Biomembr 2019; 1862:183031. [PMID: 31374213 DOI: 10.1016/j.bbamem.2019.183031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/16/2019] [Accepted: 07/25/2019] [Indexed: 11/29/2022]
Abstract
Electrostatic side chain contacts can contribute substantial interaction energy terms to the stability of proteins. The impact of electrostatic interactions on the structure and architecture of outer membrane proteins is however not well studied compared to soluble proteins. Here, we report the results of a systematic study of all charged side chains of the E. coli outer membrane protein X (OmpX). The data identify three distinct salt-bridge clusters in the core of OmpX that contribute significantly to protein stability in dodecylphosphocholine detergent micelles. The three clusters form an "electrostatic core" of the membrane protein OmpX, corresponding in its architectural role to the hydrophobic core of soluble proteins. This article is part of a Special Issue entitled: Molecular biophysics of membranes and membrane proteins.
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Affiliation(s)
- Parthasarathi Rath
- Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland
| | - Timothy Sharpe
- Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland
| | - Sebastian Hiller
- Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland.
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