Keyword search (3,448 papers available) |
Author(s): Chen S; Taing H; Ahmida M; He HY; Carr A; Muchall HM; Eichhorn SH;
Thermotropic ionic liquid crystals have remained a relatively little studied group of materials despite their many potential applications as anisotropic ionic liquids and charge (ion and electron/hole) transporting materials. Particularly rare are core char...
Article GUID: 39315415
Author(s): Toubin C; Yeung DY; English AM; Peslherbe GH;
The degradation of S-nitrosothiols (RSNOs) to release NO is believed to be catalyzed by CuI ions, but the mechanism remains unclear. Kinetic experiments have shown that decomposition rates vary significantly with the chemical nature of the RSNO considered. ...
Article GUID: 12475301
Author(s): Qadir K Timerghazin
First-principles molecular dynamics simulations of the excited-state dynamics of I-(H2O)3 have been performed to gain some insight into the general features of the relaxation process of photoexcited I-(H2O)n clusters. The relaxation of excited I-(H2O)3 is c...
Article GUID: 12914436
Author(s): Robert C Mawhinney
A combination of density-functional theory and natural resonance theory has been used to show that a complete description of the electronic structure of nitrilimines, R(1)CNNR(2), requires four resonance structures (propargylic, allenic, 1,3-dipolar and car...
Article GUID: 15306921
Author(s): Paul G Loncke
Substituent effects and the role of negative hyperconjugation in 1,2-silyl migration and decarbonylation of methoxy(substituted-siloxy)carbenes have been investigated using quantum chemical calculations and natural bond orbital analysis. It has been found t...
Article GUID: 15917909
Author(s): Denise M Koch
We have investigated the photodissociation dynamics of NaI(H(2)O)(n) [n = 1-4] clusters using the molecular dynamics with quantum transitions method and a quantum mechanics/molecular mechanics description of NaI(H(2)O)(n), which involves a semiempirical val...
Article GUID: 16435804
Author(s): Pascal Larrégaray
The unimolecular dissociation dynamics of aluminum clusters following collision with either a rare gas atom or a surface is investigated by classical trajectory simulations with model potentials. Two conformers of Al(6) with very distinct shapes, i.e., the ...
Article GUID: 16435829
Author(s): Qadir K Timerghazin
High-level ab initio calculations employing the multireference configuration interaction and coupled clusters methods with a correlation-consistent sequence of basis sets have been used to obtain accurate potential energy curves for the complex of the sodiu...
Article GUID: 16438589
Author(s): Grygoriy A Dolgonos
The C2 fragmentation energies of the most stable isolated-pentagon-rule (IPR) isomers of the C80 and C82 fullerenes were evaluated with second-order Møller-Plesset (MP2) theory, density-functional theory (DFT) and the semiempirical self-consistent charge de...
Article GUID: 17588181
Author(s): Qadir K Timerghazin
A resonance representation of the electronic structure of S-nitrosothiols as a combination of the conventional R-S-N=O structure, a zwitterionic structure R-S+=N-O-, and a RS-/NO+ ion pair is proposed. The resonance forms are employed to predict and rationa...
Article GUID: 17616141
Author(s): Qadir K Timerghazin
Two or more polar molecules can trap an excess electron either in a dipole-bound fashion where it is located outside of the cluster (dipole-bound electron) or inside the cluster (solvated electron). The topology of the electron density in dipole-bound and s...
Article GUID: 17705589
Author(s): Qadir K Timerghazin
Acetonitrile molecules are known for their intriguing ability to accommodate an excess electron in either a diffuse dipole-bound orbital, away from the valence electrons, or in its valence orbitals, depending on the environment. In this work, we report a co...
Article GUID: 18154288
Author(s): Tao-Nhân V Nguyen
The structural and thermodynamic properties of Na+(CH3CN)n, I-(CH3CN)n, and NaI(CH3CN)n clusters have been investigated by means of room-temperature Monte Carlo simulations with model potentials developed to reproduce the properties of small clusters predic...
Article GUID: 18183958
Author(s): Hernández de la Peña L; Peslherbe GH;
Nonequilibrium simulation methods and rigid-body path-integral techniques are combined to estimate the relevance of protonic quantum effects in the free energy of ion-water clusters. The Crooks' fluctuation relation is used to quantitatively characteriz...
Article GUID: 20377185
Author(s): Nguyen TN; Timerghazin QK; Vach H; Peslherbe GH;
Molecular electronic excitation in (O(2))(n) clusters induced by mechanical collisions via the "chemistry with a hammer" is investigated by a combination of molecular dynamics simulations and quantum chemistry calculations. Complete active space self-consis...
Article GUID: 21322678
Author(s): Ivanova EV; Muchall HM;
We present a computational study on the concerted hydrolysis of several classes of N-sulfinylamines of generic formula R-N-S-O, such as the -amines themselves (R-NSO), -hydrazines (R-NH-NSO), -hydrazides (R-CO-NH-NSO) and -amides (R-CO-NSO), as these specie...
Article GUID: 21428403
Author(s): Varadwaj PR; Varadwaj A; Peslherbe GH; Marques HM;
Density functional theory calculations, together with quantum theory of atoms in molecules (QTAIM) analyses, have been performed to investigate 18-azacrown-6 complexes of the high-spin late first transition series divalent metal ions in the gas phase and, i...
Article GUID: 21961695
Author(s): Wang S; Orabi EA; Baday S; Bernèche S; Lamoureux G;
Proteins of the Amt/MEP family facilitate ammonium transport across the membranes of plants, fungi, and bacteria and are essential for growth in nitrogen-poor environments. Some are known to facilitate the diffusion of the neutral NH(3), while others, notab...
Article GUID: 22631217
Author(s): Shadrina MS; English AM; Peslherbe GH;
The diffusion of small gases to special binding sites within polypeptide matrices pivotally defines the biochemical specificity and reactivity of proteins. We investigate here explicit O(2) diffusion in adult human hemoglobin (HbA) as a case study employing...
Article GUID: 22690872
Author(s): Varadwaj PR; Varadwaj A; Peslherbe GH;
The proton accepting and donating abilities of cyclopropenylidene (c-C(3)H(2)) on its complexation with hydrogen halides H-X (X = F, Cl, Br) are analyzed using density-functional theory with three functionals (PBE0, B3LYP, and B3LYP-D) and benchmarked again...
Article GUID: 22696309
Author(s): Varadwaj A; Varadwaj PR;
Based on an experimental observation, it has been controversially suggested in a study (Kurotobi et al., Science 2011, 33, 613) that a single molecule of water can completely be localized within the subnano-space inside the fullerene C(60) cage and, that ne...
Article GUID: 23090782
Author(s): Fürst O; Nichols CG; Lamoureux G; D' Avanzo N;
Cholesterol is the major sterol component of all mammalian plasma membranes. Recent studies have shown that cholesterol inhibits both bacterial (KirBac1.1 and KirBac3.1) and eukaryotic (Kir2.1) inward rectifier K(+) (Kir) channels. Lipid-sterol interactions...
Article GUID: 25517146
Author(s): Jean-François Rhéault
A singular aspect of the 2-on-2 hemoglobin structures of groups I and II is the presence of tunnels linking the protein surface to the distal heme pocket, supporting the storage and the diffusion of small apolar ligands to/from the buried active site. As th...
Article GUID: 25723781
Author(s): Sefer Baday
In human cells, membrane proteins of the rhesus (Rh) family excrete ammonium and play a role in pH regulation. Based on high-resolution structures, Rh proteins are generally understood to act as NH3 channels. Given that cell membranes are permeable to gases...
Article GUID: 26190573
Author(s): Maria S Shadrina
Atomistic molecular dynamics simulations of diffusion of O2 from the hemes to the external solvent in the a- and ß-subunits of the human hemoglobin (HbA) tetramer reveal transient gas tunnels that are not seen in crystal structures. We find here that the tu...
Article GUID: 26226318
Author(s): Maria S Shadrina
Hemoglobin transports O2 by binding the gas at its four hemes. Hydrogen bonding between the distal histidine (HisE7) and heme-bound O2 significantly increases the affinity of human hemoglobin (HbA) for this ligand. HisE7 is also proposed to regulate the rel...
Article GUID: 26226401
Author(s): Sandrine Moreira
CONCLUSION: Homology modeling and molecular dynamics simulations strongly suggest that DpRNL is an RNA ligase 2. The predicted innovative reshaping of DpRNL's catalytic pocket is worthwhile to be tested experimentally.
Article GUID: 26449279
Author(s): Esam A Orabi
A polarizable model for ammonia is optimized based on the ab initio properties of the NH3 molecule and the NH3-NH3 and NH3-H2O dimers calculated at the MP2 level. For larger (NH3)m, NH3(H2O)n, and H2O(NH3)n clusters (m = 2-7 and n = 1-4), the model yields s...
Article GUID: 26583551
Author(s): Esam A Orabi
A polarizable potential model for M(+)-NH3 interactions (M(+) = Li(+), Na(+), K(+), Rb(+), Cs(+)) is optimized based on the ab initio properties of the ion-ammonia dimers calculated at the MP2 level of theory. The optimized model reproduces the ab initio bi...
Article GUID: 26583725
Author(s): Esam A Orabi
A polarizable model for hydrogen sulfide (H2S) is optimized based on the experimental properties of the monomer and of the bulk liquid. The model is characterized by rigid SH bonds but flexible HSH angle and the polarizability is based on the Drude oscillat...
Article GUID: 26588292
Author(s): Esam A Orabi
Polarizable potential models for the interaction of Li(+), Na(+), K(+), and NH4(+) ions with benzene are parametrized based on ab initio quantum mechanical calculations. The models reproduce the ab initio complexation energies and potential energy surfaces ...
Article GUID: 26592880
Author(s): Jardali F; Tran J; Liège F; Florea I; Leulmi ME; Vach H;
The outstanding properties of silicon nanoparticles have been extensively investigated during the last few decades. Experimental evidence and applications of their theoretically predicted permanent electric dipole moment, however, have only been reported fo...
Article GUID: 37570492
Author(s): Selvaraj G; Kaliamurthi S; Peslherbe GH; Wei DQ;
ackground: Coronavirus (CoV) is an emerging human pathogen causing severe acute respiratory syndrome (SARS) around the world. Earlier identification of biomarkers for SARS can facilitate detection and reduce the mortality rate of the disease. Thus, by integ...
Article GUID: 33968364
Author(s): Ozturk TN; Culham DE; Tempelhagen L; Wood JM; Lamoureux G;
Osmosensing transporter ProP detects the increase in cytoplasmic cation concentration associated with osmotically induced cell dehydration and mediates osmolyte uptake into bacteria. ProP is a 12-transmembrane helix protein with an a-helical, cytoplasmic C-...
Article GUID: 32838524
Author(s): Simbrunner J; Schrode B; Domke J; Fritz T; Salzmann I; Resel R;
Crystal structure identification of thin organic films entails a number of technical and methodological challenges. In particular, if molecular crystals are epitaxially grown on single-crystalline substrates a complex scenario of multiple preferred orientat...
Article GUID: 32356785
Author(s): Kim VO; Broch K; Belova V; Chen YS; Gerlach A; Schreiber F; Tamura H; Della Valle RG; D' Avino G; Salzmann I; Beljonne D; Rao A; Friend...
Singlet exciton fission is a spin-allowed process in organic semiconductors by which one absorbed photon generates two triplet excitons. Theory predicts that singlet fission is mediated by intermol...
Article GUID: 31675857
Author(s): Krohn L; Öztürk TN; Vanderperre B; Ouled Amar Bencheikh B; Ruskey JA; Laurent SB; Spiegelman D; Postuma RB; Arnulf I; Hu MTM; Dauvilliers Y;...
Objective: The TMEM175/GAK/DGKQ locus is the 3rd strongest risk locus in genome-wide association studies of Parkinson disease (PD). We aimed to identify the specific disease-associated variants in ...
Article GUID: 31658403
Author(s): Orabi EA; Davis RL; Lamoureux G;
Cation-p interactions play important roles in molecular recognition and in the stability and function of proteins. However, accurate description of the structure and energetics of cation-p interactions presents a challenge to both additive and polarizable f...
Article GUID: 31652004
Author(s): Shihao Wang
This letter presents a method for the parametrization of semiempirical models for proton transfer reactions in water clusters. Two new models are developed: AM1-W, which is a reparameterization of the classic AM1 model, and AM1PG-W, which is a modified AM1-...
Article GUID: 26588263
Author(s): Adrian Paz Ramos
Little is known about the interaction of very long-chain saturated fatty acids (VLCFAs) with biological membranes. However, this could play an important role on interleaflet interactions and signal transduction mechanisms in cells. The aim of this work is t...
Article GUID: 27351151
Author(s): Prem Ponka
Heme is a cofactor that is essential to almost all forms of life. The production of heme is a balancing act between the generation of the requisite levels of the end-product and protection of the cell and/or organism against any toxic substrates, intermedia...
Article GUID: 28254242
Author(s): Lavinia A Carabet
Many globins convert ^(•)NO to innocuous NO(3)^(-) through their nitric oxide dioxygenase (NOD) activity. Mycobacterium tuberculosis fights the oxidative and nitrosative stress imposed by its host (the toxic effects of O(2)^(•-) and ^(•)NO species and their...
Article GUID: 28835102
Author(s): Lauralicia Sacre
Oligonucleotides containing various adducts, including ethyl, benzyl, 4-hydroxybutyl and 7-hydroxyheptyl groups, at the O4 atom of 5-fluoro-O4 -alkyl-2'-deoxyuridine were prepared by solid-phase synthesis. UV thermal denaturation studies demonstrated th...
Article GUID: 29243336
Author(s): Esam A Orabi
Cation-p interactions play important roles in the stabilization of protein structures and protein-ligand complexes. They contribute to the binding of quaternary ammonium ligands (mainly RNH(3)^(+) and RN(CH(3))(3)^(+)) to various protein receptors and are l...
Article GUID: 29397727
Author(s): Esam A Orabi
S-aromatic motifs are important noncovalent forces for protein stability and function but remain poorly understood. Hence, we performed quantum calculations at the MP2(full)/6-311++G(d,p) level on complexes between Cys (H(2)S, MeSH) and Met (Me(2)S) models ...
Article GUID: 29533644
Author(s): Esam A Orabi
Hydrogen peroxide (H(2)O(2)) has numerous industrial, environmental, medical, cosmetic, and biological applications. Given its importance, we provide a simple model as an alternative to experiment for studying the properties of pure liquid H(2)O(2) and its ...
Article GUID: 29630362
Author(s): Georgy Derevyanko
MOTIVATION: The computational prediction of a protein structure from its sequence generally relies on a method to assess the quality of protein models. Most assessment methods rank candidate models using heavily engineered structural features, defined as co...
Article GUID: 29931128
Author(s): Simbrunner J; Hofer S; Schrode B; Garmshausen Y; Hecht S; Resel R; Salzmann I;
Grazing-incidence X-ray diffraction studies on organic thin films are often performed on systems showing fibre-textured growth. However, indexing their experimental diffraction patterns is generally challenging, especially if low-symmetry lattices are invol...
Article GUID: 30996719
Title: | Genetic, Structural, and Functional Evidence Link TMEM175 to Synucleinopathies |
Authors: | Krohn L, Öztürk TN, Vanderperre B, Ouled Amar Bencheikh B, Ruskey JA, Laurent SB, Spiegelman D, Postuma RB, Arnulf I, Hu MTM, Dauvilliers Y, Högl B, Stefani A, Monaca CC, Plazzi G, Antelmi E, Ferini-Strambi L, Heidbreder A, Rudakou U, Cochen De Cock V, Young P, Wolf P, Oliva P, Zhang XK, Greenbaum L, Liong C, Gagnon JF, Desautels A, Hassin-Baer S, Montplaisir JY, Dupré N, Rouleau GA, Fon EA, Trempe JF, Lamoureux G, Alcalay RN, Gan-Or Z, |
Link: | https://pubmed.ncbi.nlm.nih.gov/31658403/ |
DOI: | 10.1002/ana.25629 |
Category: | Ann Neurol |
PMID: | 31658403 |
Dept Affiliation: | CERMM
1 Department of Human Genetics, McGill University, Montreal, Quebec, Canada. 2 Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada. 3 Department of Physics, Concordia University, Montreal, Quebec, Canada. 4 Centre for Research in Molecular Modeling (CERMM), Concordia University, Montreal, Quebec, Canada. 5 PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Quebec, Quebec, Canada. 6 Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada. 7 Sleep Disorders Unit, Pitié Salpêtrière Hospital, Institute of Brain and Spinal Cord and Sorbonne University, Paris, France. 8 Oxford Parkinson's Disease Centre, University of Oxford, Oxford, United Kingdom. 9 Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom. 10 National Reference Center for Narcolepsy, Sleep Unit, Department of Neurology, Gui de Chauliac Hospital, University Hospital Center Montpellier, University of Montpellier, National Institute of Health and Medical Research U1061, Montpellier, France. 11 Sleep Disorders Clinic, Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria. 12 University of Lille Nord de France, Department of Clinical Neurophysiology and Sleep Center, University Hospital Center Lille, Lille, France. 13 Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy. 14 Scientific Institute for Research and Health Care, Institute of Neurological Sciences of Bologna, Bologna, Italy. 15 Department of Neurological Sciences, Vita-Salute San Raffaele University, Milan, Italy. 16 Institute of Sleep Medicine and Neuromuscular Disorders, University of Münster, Münster, Germany. 17 Sleep and Neurology Unit, Beau Soleil Clinic, Montpellier, France. 18 EuroMov, University of Montpellier, Montpellier, France. 19 Biologics Structural and Functional Research, Biopharmaceutics Development, Genzyme, Framingham, MA. 20 Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Israel. 21 Joseph Sagol Neuroscience Center, Sheba Medical Center, Tel Hashomer, Israel. 22 Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel. 23 Department of Neurology, College of Physicians and Surgeons, Columbia University Medical Center, New York, NY. 24 Center for Advanced Research in Sleep Medicine, Sacred Heart Hospital of Montreal, Montreal, Quebec, Canada. 25 Department of Psychology, University of Quebec at Montreal, Montreal, Quebec, Canada. 26 Department of Neurosciences, University of Quebec at Montreal, Montreal, Quebec, Canada. 27 The Movement Disorders Institute, Department of Neurology, Sheba Medical Center, Tel Hashomer, Israel. 28 Department of Psychiatry, University of Montreal, Montreal, Quebec, Canada. 29 Division of Neurosciences, University Hospital Center of Quebec, Laval University, Quebec City, Quebec, Canada. 30 Department of Medicine, Faculty of Medicine, Laval University, Quebec City, Quebec, Canada. 31 Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada. 32 Department of Chemistry, Rutgers University - Camden, Camden, NJ, USA. 33 Center for Computational and Integrative Biology (CCIB), Camden, NY, USA. < |
Description: |
Objective: The TMEM175/GAK/DGKQ locus is the 3rd strongest risk locus in genome-wide association studies of Parkinson disease (PD). We aimed to identify the specific disease-associated variants in this locus, and their potential implications. Methods: Full sequencing of TMEM175/GAK/DGKQ followed by genotyping of specific associated variants was performed in PD (n = 1,575) and rapid eye movement sleep behavior disorder (RBD) patients (n = 533) and in controls (n = 1,583). Adjusted regression models and a meta-analysis were performed. Association between variants and glucocerebrosidase (GCase) activity was analyzed in 715 individuals with available data. Homology modeling, molecular dynamics simulations, and lysosomal localization experiments were performed on TMEM175 variants to determine their potential effects on structure and function. Results: Two coding variants, TMEM175 p.M393T (odds ratio [OR] = 1.37, p = 0.0003) and p.Q65P (OR = 0.72, p = 0.005), were associated with PD, and p.M393T was also associated with RBD (OR = 1.59, p = 0.001). TMEM175 p.M393T was associated with reduced GCase activity. Homology modeling and normal mode analysis demonstrated that TMEM175 p.M393T creates a polar side-chain in the hydrophobic core of the transmembrane, which could destabilize the domain and thus impair either its assembly, maturation, or trafficking. Molecular dynamics simulations demonstrated that the p.Q65P variant may increase stability and ion conductance of the transmembrane protein, and lysosomal localization was not affected by these variants. Interpretation: Coding variants in TMEM175 are likely to be responsible for the association in the TMEM175/GAK/DGKQ locus, which could be mediated by affecting GCase activity. ANN NEUROL 2020; 87:139-153. |