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Photocontrolled Biomolecules
Planer, Jakub ; Bartošík, Miroslav (referee) ; Vácha,, Robert (referee) ; Kulhánek, Petr (advisor)
This work is focused on molecular dynamics simulations of artificial photosensitive ion channel and AFM probe. To assemble this ion channel, DFT methods were employed for reparametrization of the GAFF force field describing the bridged azobenzene, which was used as a light controlled molecular switch. We proved by molecular dynamics simulations that newly developed parameters correctly describe behavior of assembled model of ion channel in a lipid bilayer. We also constructed a model of AFM probe and observed formation of water meniscus between the AFM probe and surface, both made of -quartz, by employing molecular dynamics simulations. A contribution of this work is the set of new parameters extending GAFF force field for description of the bridged azobenzene. We also verified functionality of ion channel model and model of AFM probe, which can be used for the further water meniscus studies.
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Molecular simulation study of aqueous solutions of alifatic alcohols
Peštuka, Martin ; Žídek, Jan (referee) ; Janeček, Jiří (advisor)
The aim of this bachelor thesis was to carry out set of molecular dynamic simulations of aqueous solutions of aliphatic alcohols in infinite attenuation. In order to work with molecular dynamic simulations it was necessary to become familiar with the program equipment to perform molecular dynamic simulations and analyze the results. Within the work the basic simulation boxes contained 300, 400, 500 and 1000 water molecules and one molecule of aliphatic alcohol. From the simulated trajectories we evaluated the volume change associated with the insertion of one particle of alcohol and the radial distribution functions around the molecule of solute. The results were compared with experimental data.
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Deformation mechanisms in crystals by means of molecular dynamics
Lamberský, Vojtěch ; Grepl, Robert (referee) ; Černý, Miroslav (advisor)
This work deals with molecular dynamics modeling of processes in condensed matter on atomic level. The physical principles used to predict motion of atom or molecule groups are described in the retrieval part. Then follows a description of the EAM method, ways how to parallelize computing on many processors and how perform calculation optimizing. Finally, we perform a theoretical tensile strength computation using Lammps program.
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Molecular dynamics simulations of membrane proteins
Španěl, David ; Barvík, Ivan (advisor) ; Bok, Jiří (referee)
Basic facts about the structure of biomolecules and algorithms applied in molecular dynamics (MD) simulations were recapitulated in the theoretical part of this thesis. A program for MD simulations of a periodic box with water molecules represented by various models (SPC, TIPS, TIP3P) was developed for active mastery of basic algorithms applied in MD simulations. MD simulation methodology was subsequently applied to the structure of the membrane protein A2AGPCR anchored in the phospholipid bilayer and surrounded by water molecules (approx. 120,000 atoms altogether). The purpose of these MD simulations was to compare binding of the natural agonist (adenosine) and its synthetic analog NECA into the binding pocket situated on the extracellular side of A2AGPCR. For these MD simulations were used software package NAMD and computer cluster Gram (in which each node is equipped with 16 CPU cores and 4 GPU) in supercomputing MetaCentrum. Powered by TCPDF (www.tcpdf.org)
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Molecular dynamics simulations of biomolecules
Naništa, Ján ; Barvík, Ivan (advisor) ; Bok, Jiří (referee)
This study deals with classical molecular dynamics simulations of time evolution of a biomolecular system. The simulated system consists of the D3 GPCR membrane receptor for dopamine surrounded by a cell membrane and covered with water molecules and ions. The aim was to analyze the ability of Eticlopride to bind into the active site of the GPCR receptor.
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Computer modelling of biomolecules - potential chemoterapeutics
Maláč, Kamil ; Barvík, Ivan (advisor) ; Jungwirth, Pavel (referee) ; Ettrich, Rüdiger (referee)
Classical molecular dynamics simulations were applied on complexes of RNA-dependent RNA-polymerase, Ribonuclease H, Argonaute and Ribonuclease L with chemically modified nucleic acids, which are studied as potential chemotherapeutic agents. Powerful graphics processing units, through which these molecular dynamics simulations were performed, enabled to acquire trajectory length from hundreds of nanoseconds to one microsecond. Molecular dynamics simulations allowed capture differences in binding of various modified nucleic acids to the above mentioned enzymes. These identified differences fitted well with experimental results. It opens the door for rational design of the structure of potential chemotherapeutic agents based on chemically modified nucleic acids.
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Development and applications of molecular dynamics for molecular spectroscopy
Kessler, Jiří
This Thesis deals with simulations of chiroptical spectra using a combination of molecular dynamics and quantum chemistry. Molecular dynamics was used to explore conformational behaviour of studied systems (proteins), quantum chemistry for calculation of spectral prop- erties. The Quantum chemical methods are limited to relatively small systems. We overcome this problem mostly by a fragmentation of studied systems, when smaller, computationally feasible, fragments are created and used for the quantum chemical calculations. Calculated properties were then transferred to the big molecule. Vibrational Optical Activity (VOA) spectra of poly-L-glutamic acid fibrils (PLGA), insulin prefibrillar form and native globular proteins were studied. The simulated spectra provided satisfactory agreement with the experiment and were used for its interpretation. Experimental Vibrational Circular Dichroism (VCD) spectra of poly-L-glutamic acid fibrils were only qualitatively reproduced by the simulation. We could reproduce the major amide I band and a smaller negative band associated with the side chain carboxyl group. Our simulation procedure was then extended to a set of globular proteins and their Raman Optical Activity (ROA) spectra. Here we achieved an exceptional precision. For example, we were able to reproduce...
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Computer modelling of biomolecules - potential chemoterapeutics
Maláč, Kamil ; Jungwirth, Pavel (referee)
Classical molecular dynamics simulations were applied on complexes of RNA-dependent RNA-polymerase, Ribonuclease H, Argonaute and Ribonuclease L with chemically modified nucleic acids, which are studied as potential chemotherapeutic agents. Powerful graphics processing units, through which these molecular dynamics simulations were performed, enabled to acquire trajectory length from hundreds of nanoseconds to one microsecond. Molecular dynamics simulations allowed capture differences in binding of various modified nucleic acids to the above mentioned enzymes. These identified differences fitted well with experimental results. It opens the door for rational design of the structure of potential chemotherapeutic agents based on chemically modified nucleic acids.
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Molecular dynamics simulations of ion channel TRPA1
Zíma, Vlastimil ; Barvík, Ivan (advisor) ; Ettrich, Rüdiger (referee) ; Martínek, Václav (referee)
Title: Molecular dynamics simulations of ion channel TRPA1 Author: Mgr. Vlastimil Zíma Institute: Institute of Physics of Charles University Supervisor: RNDr. Ivan Barvík, PhD., Institute of Physics of Charles Uni- versity Abstract: The ion channel TRPA1 is one of the members of the transient receptor potential channel family. These channels have recently been an im- portant objective of research, because they play important roles in various cellular processes and organismic mechanisms. Especially they are involved in most of the senses. We focused mainly on the TRPA1 ion channel due to its involvement in the pain sensation in humans. Because the molecular mechanisms behind the gating of this channel are not fully understood, their description is a key for a design of new analgesics targeting this channel. We used a homology modeling and molecular dynamics simulations in conjunc- tion with electrophysiological experiments to provide a valuable new insight into the channel mechanisms. We contributed by describing of a putative binding site for calcium ions. Further, many functionally important amino acids were found in the S1-S4 transmembrane domain. Keywords: voltage-gated ion channel, TRPA1 channel, molecular dynamics, homology modeling 1
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