The delineation of protein-lipid interfaces is essential for understanding the mechanisms of various membrane-associated processes crucial to plant development and growth, including signalling, trafficking, and membrane transport. Due to their highly dynamic nature, the precise characterization of lipid-protein interactions by experimental techniques is challenging. Molecular dynamics simulations provide a powerful computational alternative with a spatial-temporal resolution allowing the atomistic-level description. In this review, we aim to introduce plant scientists to molecular dynamics simulations. We describe different steps of performing molecular dynamics simulations and provide a broad survey of molecular dynamics studies investigating plant protein-lipid interfaces. Our aim is also to illustrate that combining molecular dynamics simulations with artificial intelligence-based protein structure determination opens up unprecedented possibilities for future investigations of dynamic plant protein-lipid interfaces.

• Klíčová slova
• Integral membrane protein, membrane, molecular dynamics simulations, peripheral membrane protein, protein–lipid interactions, structural modelling,
• MeSH
• rostlinné proteiny * metabolismus   chemie   MeSH
• rostliny metabolismus   MeSH
• simulace molekulární dynamiky * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• rostlinné proteiny * MeSH

Intense pulsed electric fields are known to act at the cell membrane level and are already being exploited in biomedical and biotechnological applications. However, it is not clear if electric pulses within biomedically-attainable parameters could directly influence intra-cellular components such as cytoskeletal proteins. If so, a molecular mechanism of action could be uncovered for therapeutic applications of such electric fields. To help clarify this question, we first identified that a tubulin heterodimer is a natural biological target for intense electric fields due to its exceptional electric properties and crucial roles played in cell division. Using molecular dynamics simulations, we then demonstrated that an intense - yet experimentally attainable - electric field of nanosecond duration can affect the bβ-tubulin's C-terminus conformations and also influence local electrostatic properties at the GTPase as well as the binding sites of major tubulin drugs site. Our results suggest that intense nanosecond electric pulses could be used for physical modulation of microtubule dynamics. Since a nanosecond pulsed electric field can penetrate the tissues and cellular membranes due to its broadband spectrum, our results are also potentially significant for the development of new therapeutic protocols.

• MeSH
• elektrická stimulace * metody   MeSH
• lidé MeSH
• simulace molekulární dynamiky * MeSH
• statická elektřina MeSH
• tubulin fyziologie   MeSH
• vazebná místa MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• tubulin MeSH

Molecular dynamics simulations help to understand the complex behavior of molecules. The output of such a simulation describes the trajectories of individual atoms as snapshots of atom positions in time. Many compression schemes were developed to reduce the amount of data needed for storing long trajectories. This is achieved by limiting the precision of coordinates, encoding differences instead of absolute values, dimensionality reduction by principal component analysis, or by using polynomials approximating vertex trajectories. However, compression schemes using actual bonds between atoms have not been utilized to their full potential. Therefore, we developed a lossy compression method that captures the local, mostly rotational movement of atoms with respect to their bonded neighbors and predicts their positions in each frame. This allows full control over the data distortion. In our experiments, the method achieves data rates which are substantially better than the rates achieved by competing methods at the same error level.

• Klíčová slova
• 2010 MSC: 92C40, 68P30, Compression, Encoding, Graph traversal, Molecular dynamics, Molecular simulations, Trajectory,
• MeSH
• algoritmy * MeSH
• analýza hlavních komponent MeSH
• simulace molekulární dynamiky * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Kinesin is a biological molecular nanomotor which converts chemical energy into mechanical work. To fulfill various nanotechnological tasks in engineered environments, the function of biological molecular motors can be altered by artificial chemical modifications. The drawback of this approach is the necessity of designing and creating a new motor construct for every new task. We propose that intense nanosecond-scale pulsed electric field could modify the function of nanomotors. To explore this hypothesis, we performed molecular dynamics simulation of a kinesin motor domain docked on a subunit of its microtubule track - a single tubulin heterodimer. In the simulation, we exposed the kinesin motor domain to intense (100 MV/m) electric field up to 30 ns. We found that both the magnitude and angle of the kinesin dipole moment are affected. Furthermore, we found that the electric field affects contact surface area between kinesin and tubulin, the structure and dynamics of the functionally important kinesin segments, including microtubule binding motifs as well as nucleotide hydrolysis site which power the nanomotor. These findings indicate that external intense nanosecond-scale electric field could alter kinesin behavior. Our results contribute to developing novel electromagnetic methods for modulating the function of biomolecular matter at the nanoscale.

• MeSH
• časové faktory MeSH
• elektřina * MeSH
• kineziny chemie   metabolismus   MeSH
• reprodukovatelnost výsledků MeSH
• simulace molekulární dynamiky * MeSH
• tubulin metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kineziny MeSH
• tubulin MeSH

The article reviews the application of biomolecular simulation methods to understand the structure, dynamics and interactions of nucleic acids with a focus on explicit solvent molecular dynamics simulations of guanine quadruplex (G-DNA and G-RNA) molecules. While primarily dealing with these exciting and highly relevant four-stranded systems, where recent and past simulations have provided several interesting results and novel insight into G-DNA structure, the review provides some general perspectives on the applicability of the simulation techniques to nucleic acids.

• MeSH
• DNA chemie   MeSH
• G-kvadruplexy * MeSH
• guanin chemie   MeSH
• konformace nukleové kyseliny MeSH
• ligandy MeSH
• RNA chemie   MeSH
• rozpouštědla chemie   MeSH
• simulace molekulární dynamiky * MeSH
• telomery chemie   MeSH
• vodíková vazba MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• DNA MeSH
• guanin MeSH
• ligandy MeSH
• RNA MeSH
• rozpouštědla MeSH

The tear film is a thin multilayered structure covering the cornea. Its outermost layer is a lipid film underneath of which resides on an aqueous layer. This tear film lipid layer (TFLL) is itself a complex structure, formed by both polar and nonpolar lipids. It was recently suggested that due to tear film dynamics, TFLL contains inhomogeneities in the form of polar lipid aggregates. The aqueous phase of tear film contains lachrymal-origin proteins, whereby lysozyme is the most abundant. These proteins can alter TFLL properties, mainly by reducing its surface tension. However, a detailed nature of protein-lipid interactions in tear film is not known. We investigate the interactions of lysozyme with TFLL in molecular details by employing coarse-grained molecular dynamics simulations. We demonstrate that lysozyme, due to lateral restructuring of TFLL, is able to penetrate the tear lipid film embedded in inverse micellar aggregates.

• Klíčová slova
• Lipid-protein interaction, Lysozyme, Molecular dynamics, Tear film, Tear film lipid layer,
• MeSH
• adsorpce MeSH
• estery cholesterolu chemie   MeSH
• fosfatidylcholiny chemie   MeSH
• fosfatidylethanolaminy chemie   MeSH
• kinetika MeSH
• lidé MeSH
• muramidasa chemie   MeSH
• povrchové napětí MeSH
• sfingomyeliny chemie   MeSH
• simulace molekulární dynamiky * MeSH
• slzy chemie   MeSH
• sulfoglykosfingolipidy chemie   MeSH
• termodynamika MeSH
• triolein chemie   MeSH
• voda chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 1-palmitoyl-2-oleoylphosphatidylcholine MeSH Prohlížeč
• 1-palmitoyl-2-oleoylphosphatidylethanolamine MeSH Prohlížeč
• cholesteryl oleate MeSH Prohlížeč
• estery cholesterolu MeSH
• fosfatidylcholiny MeSH
• fosfatidylethanolaminy MeSH
• muramidasa MeSH
• sfingomyeliny MeSH
• sulfoglykosfingolipidy MeSH
• triolein MeSH
• voda MeSH

We employed all-atom MD simulations to investigate the impact of palmitoylation on the PAG transmembrane peptide within various lipid environments, including the less explored boundary region separating lipid-ordered (Lo) and lipid-disordered (Ld) membrane phases. We found that palmitoylation of the peptide reduces its impact on membrane thickness, particularly within the Lo and boundary environments. Despite their hydrophobic nature, the palmitoyl chains on the peptide did not significantly affect the hydration of the surrounding membrane. Interestingly, the boundary membrane environment was found to be especially compatible with the palmitoylated peptide, suggesting its potential for accumulation in phase boundaries. Our findings highlight the importance of understanding how palmitoylation-modified peptides behave within membranes, with crucial implications for cell signaling and membrane organization. This knowledge may also inform the optimization of lipid membrane-based drug delivery systems, by improving our understanding of how drugs and excipients can be most effectively arranged within these carriers.

• Klíčová slova
• Lipid membrane phases, MD simulations, Membranes, PAG, Palmitoylation,
• MeSH
• lipidové dvojvrstvy * chemie   MeSH
• lipoylace MeSH
• peptidy metabolismus   MeSH
• simulace molekulární dynamiky * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• lipidové dvojvrstvy * MeSH
• peptidy MeSH

Given by χ torsional angles, rotamers describe the side-chain conformations of amino acid residues in a protein based on the rotational isomers (hence the word rotamer). Constructed rotamer libraries, based on either protein crystal structures or dynamics studies, are the tools for classifying rotamers (torsional angles) in a way that reflect their frequency in nature. Rotamer libraries are routinely used in structure modeling and evaluation. In this perspective article, we would like to encourage researchers to apply rotamer analyses beyond their traditional use. Molecular dynamics (MD) of proteins highlight the in silico behavior of molecules in solution and thus can identify favorable side-chain conformations. In this article, we used simple computational tools to study rotamer dynamics (RD) in MD simulations. First, we isolated each frame in the MD trajectories in separate Protein Data Bank files via the cpptraj module in AMBER. Then, we extracted torsional angles via the Bio3D module in R language. The classification of torsional angles was also done in R according to the penultimate rotamer library. RD analysis is useful for various applications such as protein folding, study of rotamer-rotamer relationship in protein-protein interaction, real-time correlation between secondary structures and rotamers, study of flexibility of side chains in binding site for molecular docking preparations, use of RD as guide in functional analysis and study of structural changes caused by mutations, providing parameters for improving coarse-grained MD accuracy and speed, and many others. Major challenges facing RD to emerge as a new scientific field involve the validation of results via easy, inexpensive wet-lab methods. This realm is yet to be explored.

• MeSH
• isomerie MeSH
• konformace proteinů MeSH
• proteiny chemie   MeSH
• rotace * MeSH
• simulace molekulární dynamiky * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• proteiny MeSH

The L1 stalk is a prominent mobile element of the large ribosomal subunit. We explore the structure and dynamics of its non-canonical rRNA elements, which include two kink-turns, an internal loop, and a tetraloop. We use bioinformatics to identify the L1 stalk RNA conservation patterns and carry out over 11.5 μs of MD simulations for a set of systems ranging from isolated RNA building blocks up to complexes of L1 stalk rRNA with the L1 protein and tRNA fragment. We show that the L1 stalk tetraloop has an unusual GNNA or UNNG conservation pattern deviating from major GNRA and YNMG RNA tetraloop families. We suggest that this deviation is related to a highly conserved tertiary contact within the L1 stalk. The available X-ray structures contain only UCCG tetraloops which in addition differ in orientation (anti vs syn) of the guanine. Our analysis suggests that the anti orientation might be a mis-refinement, although even the anti interaction would be compatible with the sequence pattern and observed tertiary interaction. Alternatively, the anti conformation may be a real substate whose population could be pH-dependent, since the guanine syn orientation requires protonation of cytosine in the tertiary contact. In absence of structural data, we use molecular modeling to explore the GCCA tetraloop that is dominant in bacteria and suggest that the GCCA tetraloop is structurally similar to the YNMG tetraloop. Kink-turn Kt-77 is unusual due to its 11-nucleotide bulge. The simulations indicate that the long bulge is a stalk-specific eight-nucleotide insertion into consensual kink-turn only subtly modifying its structural dynamics. We discuss a possible evolutionary role of helix H78 and a mechanism of L1 stalk interaction with tRNA. We also assess the simulation methodology. The simulations provide a good description of the studied systems with the latest bsc0χOL3 force field showing improved performance. Still, even bsc0χOL3 is unable to fully stabilize an essential sugar-edge H-bond between the bulge and non-canonical stem of the kink-turn. Inclusion of Mg(2+) ions may deteriorate the simulations. On the other hand, monovalent ions can in simulations readily occupy experimental Mg(2+) binding sites.

• MeSH
• molekulární modely MeSH
• ribozomální proteiny chemie   MeSH
• RNA ribozomální chemie   MeSH
• simulace molekulární dynamiky * MeSH
• Sulfolobus acidocaldarius chemie   MeSH
• výpočetní biologie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ribosomal protein L1 MeSH Prohlížeč
• ribozomální proteiny MeSH
• RNA ribozomální MeSH

Coxiella burnetii is a gram-negative bacterium able to infect several eukaryotic cells, mainly monocytes and macrophages. It is found widely in nature with ticks, birds, and mammals as major hosts. C. burnetii is also the biological warfare agent that causes Q fever, a disease that has no vaccine or proven chemotherapy available. Considering the current geopolitical context, this fact reinforces the need for discovering new treatments and molecular targets for drug design against C. burnetii. Among the main molecular targets against bacterial diseases reported, the enzyme dihydrofolate reductase (DHFR) has been investigated for several infectious diseases. In the present work, we applied molecular modeling techniques to evaluate the interactions of known DHFR inhibitors in the active sites of human and C. burnetii DHFR (HssDHFR and CbDHFR) in order to investigate their potential as selective inhibitors of CbDHFR. Results showed that most of the ligands studied compete for the binding site of the substrate more effectively than the reference drug trimethoprim. Also the most promising compounds were proposed as leads for the drug design of potential CbDHFR inhibitors.

• Klíčová slova
• Coxiella burnetii, Q fever, dihydrofolate reductase, docking, molecular dynamics,
• MeSH
• antagonisté kyseliny listové chemie   farmakologie   MeSH
• bakteriální proteiny antagonisté a inhibitory   MeSH
• Coxiella burnetii účinky léků   metabolismus   MeSH
• dihydrofolátreduktasa chemie   metabolismus   MeSH
• katalytická doména MeSH
• lidé MeSH
• ligandy MeSH
• racionální návrh léčiv MeSH
• simulace molekulární dynamiky MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antagonisté kyseliny listové MeSH
• bakteriální proteiny MeSH
• dihydrofolátreduktasa MeSH
• ligandy MeSH