@article {2020|2124, title = {Temperature Unmasks Allosteric Propensity in a Thermophilic Malate Dehydrogenase via Dewetting and Collapse}, journal = {The Journal of Physical Chemistry B}, volume = {124}, year = {2020}, pages = {1001-1008}, doi = {10.1021/acs.jpcb.9b10776}, url = {https://doi.org/10.1021/acs.jpcb.9b10776}, author = {Katava, M. and Marchi, M. and Madern, D. and Sztucki, M. and Maccarini, M. and Sterpone, F.} } @article {2016|1656, title = {Coarse-grained and All-atom Simulations towards the Early and Late Steps of Amyloid Fibril Formation}, journal = {Isr. J. Chem.}, volume = {DOI: 10.1002/ijch.201600048.}, year = {2016}, author = {M. Chiricotto and Thanh-Thuy Tran and Phuong Hoang Nguyen and S. Melchionna and Fabio Sterpone and Philippe Derreumaux} } @article {2016|1712, title = {Dimerization Mechanism of Alzheimer A beta(40) Peptides: The High Content of Intrapeptide-Stabilized Conformations in A2V and A2T Heterozygous Dimers Retards Amyloid Fibril Formation}, journal = {J. Phys. Chem. B}, volume = {120}, number = {47}, year = {2016}, pages = {12111{\textendash}12126}, abstract = {Amyloid beta (A beta) oligomerization is associated with the origin and progression of Alzheimer{\textquoteright}s disease (AD). While the A2V mutation enhances aggregation kinetics and toxicity, mixtures of wild-type (WT) and A2V, and also WT and A2T, peptides retard fibril formation and protect against AD. In this study, we simulate the equilibrium ensemble of WT:A2T A beta(40) dimer by means of extensive atomistic replica exchange molecular dynamics and compare our results with previous equivalent simulations of A2V:A2V, WT:WT, and WT:A2V A beta(40) dimers for a total time scale of nearly 0.1 ms. Qualitative comparison of the resulting thermodynamic properties, such as the relative binding free energies, with the reported experimental kinetic and thermodynamic data affords us important insight into the conversion from slow-pathway to fast-pathway dimer conformations. The crucial reaction coordinate or driving force of such transformation turns out to be related to hydrophobic interpeptide interactions. Analysis of the equilibrium ensembles shows that the fast-pathway conformations contain interpeptide out-of-register antiparallel beta-sheet structures at short interpeptide distances. In contrast, the slow-pathway conformations are formed by the association of peptides at large interpeptide distances and high intrapeptide compactness, such as conformations containing intramolecular three-stranded beta-sheets which sharply distinguish fast (A2V:A2V and WT:WT) and slow (WT:A2T and WT:A2V) amyloid-forming sequences. Also, this analysis leads us to predict that a molecule stabilizing the intramolecular three-stranded beta-sheet or inhibiting the formation of an interpeptide beta-sheet spanning residues 17-20 and 31-37 would further reduce fibril formation and probably the cytotoxicity of A beta species.}, issn = {1520-6106}, doi = {10.1021/acs.jpcp.6b10722}, author = {Phuong Hoang Nguyen and Fabio Sterpone and Pouplana, Ramon and Philippe Derreumaux and Campanera, Josep M.} } @conference {2016|1607, title = {Hydrodynamic Effects on Amyloid-beta Aggregation}, booktitle = {Biophys. J.}, volume = {110}, number = {3, 1}, year = {2016}, note = {60th Annual Meeting of the Biophysical-Society, Los Angeles, CA, FEB 27-MAR 02, 2016}, month = {feb}, pages = {219A}, publisher = {Biophys Soc}, organization = {Biophys Soc}, issn = {0006-3495}, author = {Chiricotto, Mara and Melchionna, Simone and Philippe Derreumaux and Fabio Sterpone} } @article {2016|1702, title = {Hydrodynamic effects on beta-amyloid (16-22) peptide aggregation}, journal = {J. Chem. Phys.}, volume = {145}, number = {3}, year = {2016}, month = {jul}, abstract = {Computer simulations based on simplified representations are routinely used to explore the early steps of amyloid aggregation. However, when protein models with implicit solvent are employed, these simulations miss the effect of solvent induced correlations on the aggregation kinetics and lifetimes of metastable states. In this work, we apply the multi-scale Lattice Boltzmann Molecular Dynamics technique (LBMD) to investigate the initial aggregation phases of the amyloid A beta(16-22) peptide. LBMD includes naturally hydrodynamic interactions (HIs) via a kinetic on-lattice representation of the fluid kinetics. The peptides are represented by the flexible OPEP coarse-grained force field. First, we have tuned the essential parameters that control the coupling between the molecular and fluid evolutions in order to reproduce the experimental diffusivity of elementary species. The method is then deployed to investigate the effect of HIs on the aggregation of 100 and 1000 A beta(16-22) peptides. We show that HIs clearly impact the aggregation process and the fluctuations of the oligomer sizes by favouring the fusion and exchange dynamics of oligomers between aggregates. HIs also guide the growth of the leading largest cluster. For the 100 A beta(16-22) peptide system, the simulation of similar to 300 ns allowed us to observe the transition from ellipsoidal assemblies to an elongated and slightly twisted aggregate involving almost the totality of the peptides. For the 1000 A beta(16-22) peptides, a system of unprecedented size at quasi-atomistic resolution, we were able to explore a branched disordered fibril-like structure that has never been described by other computer simulations, but has been observed experimentally. Published by AIP Publishing.}, issn = {0021-9606}, doi = {10.1063/1.4958323}, author = {Chiricotto, Mara and Melchionna, Simone and Philippe Derreumaux and Fabio Sterpone} } @article {2016|1578, title = {Impact of the A2V Mutation on the Heterozygous and Homozygous A beta 1-40 Dimer Structures from Atomistic Simulations}, journal = {Acs Chem. Neurosci.}, volume = {7}, number = {6}, year = {2016}, month = {jun}, pages = {823{\textendash}832}, abstract = {The A2V mutation was reported to protect from Alzheimer{\textquoteright}s disease in its heterozygous form and cause an early Alzheimer{\textquoteright}s disease type dementia in its homozygous form. Experiments showed that the aggregation rate follows the order A2V > WT (wild-type) > A2V-WT. To understand the impact of this mutation, we carried out replica exchange molecular dynamics simulations of A beta 1-40 WT-A2V and A2V-A2V dimers and compared to the WT dimer. Our atomistic simulations reveal that the mean secondary structure remains constant, but there are substantial differences in the intramolecular and intermolecular conformations upon single and double A2V mutation. Upon single mutation, the intrinsic disorder is reduced, the intermolecular potential energies are reduced, the population of intramolecular three-stranded beta-sheets is increased, and the number of all a dimer topologies is decreased. Taken together, these results offer an explanation for the reduced aggregation rate of the A beta 1-40 A2V-WT peptides and the protective effect of A2V in heterozygotes.}, issn = {1948-7193}, doi = {10.1021/acschemneuro.6b00053}, author = {Phuong Hoang Nguyen and Fabio Sterpone and Campanera, Josep M. and Nasica-Labouze, Jessica and Philippe Derreumaux} } @article {2016|1735, title = {Multiscale simulation of molecular processes in cellular environments}, journal = {Philosophical Transactions of the Royal Society A-mathematical Physical and Engineering Sciences}, volume = {374}, number = {2080}, year = {2016}, abstract = {We describe the recent advances in studying biological systems via multiscale simulations. Our scheme is based on a coarse-grained representation of the macromolecules and a mesoscopic description of the solvent. The dual technique handles particles, the aqueous solvent and their mutual exchange of forces resulting in a stable and accurate methodology allowing biosystems of unprecedented size to be simulated. This article is part of the themed issue {\textquoteleft}Multiscale modelling at the physics-chemistry-biology interface{\textquoteright}.}, issn = {1364-503X}, doi = {10.1098/rsta.2016.0225}, author = {Chiricotto, Mara and Fabio Sterpone and Philippe Derreumaux and Melchionna, Simone} } @article {2016|1687, title = {Stability and Function at High Temperature. What Makes a Thermophilic GTPase Different from Its Mesophilic Homologue}, journal = {J. Phys. Chem. B}, volume = {120}, year = {2016}, pages = {2721{\textendash}2730}, abstract = {

Comparing homologous enzymes adapted to different thermal environments aids to shed light on their delicate stability/function trade-off. Protein mechanical rigidity was postulated to secure stability and high-temperature functionality of thermophilic proteins. In this work, we challenge the corresponding-state principle for a pair of homologous GTPase domains by performing extensive molecular dynamics simulations, applying conformational and kinetic clustering, as well as exploiting an enhanced sampling technique (REST2). While it was formerly shown that enhanced protein flexibility and high temperature stability can coexist in the apo hyperthermophilic variant, here we focus on the holo states of both homologues by mimicking the enzymatic turnover. We clearly show that the presence of the ligands affects the conformational landscape visited by the proteins, and that the corresponding state principle applies for some functional modes. Namely, in the hyperthermophilic species, the flexibility of the effec...

}, issn = {15205207}, doi = {10.1021/acs.jpcb.6b00306}, author = {Katava, Marina and Kalimeri, Maria and Guillaume Stirnemann and Fabio Sterpone} } @article {2016|1764, title = {Thermal activation of {\textquoteleft}allosteric-like{\textquoteright} large-scale motions in a eukaryotic Lactate Dehydrogenase.}, journal = {Sci. Reports}, volume = {7}, year = {2016}, pages = {41092}, author = {M. Katava and M. Maccarini and G. Villain and A. Paciaroni and M. Sztucki and O. Ivanova and D. Madern and Fabio Sterpone} } @conference {2016|1608, title = {Toward Microscopic Simulations of Proteins in Cell-Like Environments}, booktitle = {Biophys. J.}, volume = {110}, number = {3, 1}, year = {2016}, note = {60th Annual Meeting of the Biophysical-Society, Los Angeles, CA, FEB 27-MAR 02, 2016}, month = {feb}, pages = {386A}, publisher = {Biophys Soc}, organization = {Biophys Soc}, issn = {0006-3495}, author = {Fabio Sterpone and Philippe Derreumaux and Melchionna, Simone} } @article {2016|1633, title = {Water Determines the Structure and Dynamics of Proteins}, journal = {Chem. Rev.}, volume = {116}, year = {2016}, pages = {7673{\textendash}7697}, author = {M-C. Bellissent-Funel and A. Hassanali and M. Havenith and R. Henchman and P. Pohl and Fabio Sterpone and D. van der Spoel and Y. Xu and A. E. Garcia} } @article {2015|1634, title = {Amyloid beta Protein and Alzheimer{\textquoteright}s Disease: When Computer Simulations Complement Experimental Studies}, journal = {Chem. Rev.}, volume = {115}, number = {9}, year = {2015}, month = {may}, pages = {3518{\textendash}3563}, doi = {10.1021/cr500638n}, author = {Nasica-Labouze, Jessica and Phuong Hoang Nguyen and Fabio Sterpone and Berthoumieu, Olivia and Buchete, Nicolae-Viorel and Cote, Sebastien and De Simone, Alfonso and Doig, Andrew J. and Faller, Peter and Garcia, Angel and Laio, Alessandro and Li, Mai Suan and Melchionna, Simone and Mousseau, Normand and Mu, Yuguang and Paravastu, Anant and Pasquali, Samuela and Rosenman, David J. and Strodel, Birgit and Tarus, Bogdan and Viles, John H. and Zhang, Tong and Wang, Chunyu and Philippe Derreumaux} } @article {2015|1910, title = {Are coarse-grained models apt to detect protein thermal stability? The case of \{OPEP\} force field}, journal = {J. Non-cryst. Solids}, volume = {407}, year = {2015}, note = {7th IDMRCS: Relaxation in Complex Systems}, pages = {494{\textendash}501}, keywords = {Conformational substates network}, doi = {10.1016/j.jnoncrysol.2014.07.005}, url = {http://www.sciencedirect.com/science/article/pii/S0022309314002889}, author = {Maria Kalimeri and Philippe Derreumaux and Fabio Sterpone} } @article {2015|1709, title = {Protein Simulations in Fluids: Coupling the OPEP Coarse-Grained Force Field with Hydrodynamics}, journal = {J. Chem. Theory Comput.}, volume = {11}, number = {4}, year = {2015}, month = {apr}, pages = {1843{\textendash}1853}, doi = {10.1021/ct501015h}, author = {Fabio Sterpone and Philippe Derreumaux and Melchionna, Simone} } @article {2015|1677, title = {Recovering protein thermal stability using all-atom Hamiltonian replica-exchange simulations in explicit solvent}, journal = {J. Chem. Theo. Comput.}, volume = {11}, year = {2015}, pages = {5573{\textendash}5577}, abstract = {

The REST2 method is successfully applied to investigate the thermal stability of chignolin CLN025 and of Trp-cage. As opposed to temperature replica exchange, REST2 relies on the rescaling of the protein potential energy, which allows a smaller number of replicas. The shape of the stability curve reconstructed on the basis of the corresponding-state principle is in very good agreement with experimental data; for chignolin, the effect of mutations is also recovered.

}, issn = {15499626}, doi = {10.1021/acs.jctc.5b00954}, author = {Guillaume Stirnemann and Fabio Sterpone} } @article {2015|1668, title = {Role of Internal Water on Protein Thermal Stability: The Case of Homologous G Domains.}, journal = {J. Phys. Chem. B}, volume = {119}, year = {2015}, month = {jul}, pages = {8939{\textendash}49}, abstract = {

In this work, we address the question of whether the enhanced stability of thermophilic proteins has a direct connection with internal hydration. Our model systems are two homologous G domains of different stability: the mesophilic G domain of the elongation factor thermal unstable protein from E. coli and the hyperthermophilic G domain of the EF-1α protein from S. solfataricus. Using molecular dynamics simulation at the microsecond time scale, we show that both proteins host water molecules in internal cavities and that these molecules exchange with the external solution in the nanosecond time scale. The hydration free energy of these sites evaluated via extensive calculations is found to be favorable for both systems, with the hyperthermophilic protein offering a slightly more favorable environment to host water molecules. We estimate that, under ambient conditions, the free energy gain due to internal hydration is about 1.3 kcal/mol in favor of the hyperthermophilic variant. However, we also find that, at the high working temperature of the hyperthermophile, the cavities are rather dehydrated, meaning that under extreme conditions other molecular factors secure the stability of the protein. Interestingly, we detect a clear correlation between the hydration of internal cavities and the protein conformational landscape. The emerging picture is that internal hydration is an effective observable to probe the conformational landscape of proteins. In the specific context of our investigation, the analysis confirms that the hyperthermophilic G domain is characterized by multiple states and it has a more flexible structure than its mesophilic homologue.

}, issn = {1520-5207}, doi = {10.1021/jp507571u}, author = {Rahaman, Obaidur and Kalimeri, Maria and Melchionna, Simone and J{\'e}r{\^o}me H{\'e}nin and Fabio Sterpone} } @article {2015|1769, title = {Stay Wet, Stay Stable? How Internal Water Helps the Stability of Thermophilic Proteins}, journal = {The Journal of Physical Chemistry B}, volume = {119}, number = {40}, year = {2015}, pages = {12760{\textendash}12770}, publisher = {American Chemical Society}, author = {Chakraborty, Debashree and Antoine Taly and Fabio Sterpone} } @article {2015|1714, title = {Structures of the Alzheimer{\textquoteright}s Wild-Type A beta 1-40 Dimer from Atomistic Simulations}, journal = {J. Phys. Chem. B}, volume = {119}, number = {33}, year = {2015}, pages = {10478{\textendash}10487}, doi = {10.1021/acs.jpcb.5b05593}, author = {Tarus, Bogdan and Thanh-Thuy Tran and Nasica-Labouze, Jessica and Fabio Sterpone and Phuong Hoang Nguyen and Philippe Derreumaux} } @article {2013|1956, title = {The effect of protein composition on hydration dynamics}, journal = {Phys. Chem. Chem. Phys.}, volume = {15}, number = {10}, year = {2013}, pages = {3570{\textendash}3576}, publisher = {The Royal Society of Chemistry}, abstract = {Water dynamics at the surface of two homologous proteins with different thermal resistances is found to be unaffected by the different underlying amino-acid compositions{,} and when proteins are folded it responds similarly to temperature variations. Upon unfolding the water dynamics slowdown with respect to bulk decreases by a factor of two. Our findings are explained by the dominant topological perturbation induced by the protein on the water hydrogen bond dynamics.}, author = {Rahaman, O. and Melchionna, S. and Laage, D. and Sterpone, F.} } @article {2012|1488, title = {Magnitude and molecular origin of water slowdown next to a protein}, journal = {J. Am. Chem. Soc.}, volume = {134}, year = {2012}, pages = {4116{\textendash}4119}, abstract = {

Hydration shell dynamics plays a critical role in protein folding and biochemical activity and has thus been actively studied through a broad range of techniques. While all observations concur with a slowdown of water dynamics relative to the bulk, the magnitude and molecular origin of this retardation remain unclear. Via numerical simulations and theoretical modeling, we establish a molecular description of protein hydration dynamics and identify the key protein features that govern it. Through detailed microscopic mapping of the water reorientation and hydrogen-bond (HB) dynamics around lysozyme, we first determine that 80\% of the hydration layer waters experience a moderate slowdown factor of \~{}2-3, while the slower residual population is distributed along a power-law tail, in quantitative agreement with recent NMR results. We then establish that the water reorientation mechanism at the protein interface is dominated by large angular jumps similar to the bulk situation. A theoretical extended jump model is shown to provide the first rigorous determination of the two key contributions to the observed slowdown: a topological excluded-volume factor resulting from the local protein geometry, which governs the dynamics of the fastest 80\% of the waters, and a free energetic factor arising from the water-protein HB strength, which is especially important for the remaining waters in confined sites at the protein interface. These simple local factors are shown to provide a nearly quantitative description of the hydration shell dynamics.

}, issn = {00027863}, author = {Fabio Sterpone and Guillaume Stirnemann and Laage, Damien} } @article {2011|1771, title = {Coherent Excitation Transfer Driven by Torsional Dynamics: a Model Hamiltonian for PPV Type Systems}, journal = {Zeitschrift F{\"u}r Physikalische Chemie}, volume = {255}, year = {2011}, pages = {541{\textendash}551}, author = {Fabio Sterpone and R. Martinazzo and A.N. Panda and I. Burghardt} } @article {2011|1690, title = {Dynamics of water in concentrated solutions of amphiphiles: Key roles of local structure and aggregation}, journal = {J. Phys. Chem. B}, volume = {115}, year = {2011}, pages = {3254{\textendash}3262}, abstract = {

Water translational and reorientational dynamics in concentrated solutions of amphiphiles are investigated through molecular dynamics simulations and analytic modeling. We evidence the critical importance of the solute concentration in determining the magnitude of the slowdown in water dynamics compared to the bulk situation. The comparison of concentrated aqueous solutions of tetramethylurea, which tends to aggregate, and of trimethylamine N-oxide, which does not, shows the dramatic impact of solute clustering on the water dynamics. No significant decoupling of the reorientation and translation dynamics of water is observed, even at very high solute concentrations. The respective roles of energetic and topological disorders in determining the translational subdiffusive water dynamics in these confining environments are discussed. The water reorientational dynamics is shown to be quantitatively described by an extended jump model which combines two factors determined by the local structure: the transition-state excluded volume and the transition-state hydrogen-bond strength.

}, issn = {15206106}, author = {Guillaume Stirnemann and Fabio Sterpone and Laage, Damien} } @article {2011|1383, title = {Reorientation and Allied Dynamics in Water and Aqueous Solutions}, journal = {Annu. Rev. Phys. Chem.}, volume = {62}, year = {2011}, pages = {395{\textendash}416}, abstract = {

The reorientation of a water molecule is important for a host of phenomena, ranging over?in an only partial listing?the key dynamic hydrogen-bond network restructuring of water itself, aqueous solution chemical reaction mechanisms and rates, ion transport in aqueous solution and membranes, protein folding, and enzymatic activity. This review focuses on water reorientation and related dynamics in pure water, and for aqueous solutes with hydrophobic, hydrophilic, and amphiphilic character, ranging from tetramethylurea to halide ions and amino acids. Attention is given to the application of theory, simulation, and experiment in the probing of these dynamics, in usefully describing them, and in assessing the description. Special emphasis is placed on a novel sudden, large-amplitude jump mechanism for water reorientation, which contrasts with the commonly assumed Debye rotational diffusion mechanism, characterized by small-amplitude angular motion. Some open questions and directions for further research are also discussed. Expected final online publication date for the Annual Review of Physical Chemistry Volume 62 is March 31, 2011. Please see http://www.annualreviews.org/catalog/pubdates.aspx for revised estimates.

}, isbn = {0066-426X 1545-1593}, issn = {0066-426X}, doi = {doi: 10.1146/annurev.physchem.012809.103503}, url = {http://www.annualreviews.org/doi/abs/10.1146/annurev.physchem.012809.103503$\backslash$nhttp://www.annualreviews.org.login.ezproxy.lib.purdue.edu/doi/pdf/10.1146/annurev.physchem.012809.103503}, author = {Laage, Damien and Guillaume Stirnemann and Fabio Sterpone and Rey, Rossend and Hynes, James T.} } @inbook {2011|1773, title = {Role of packing, hydration and fluctuation on Thermostability}, booktitle = {Thermostable Proteins Structural Stability and Design}, year = {2011}, publisher = {CRC Press - Taylor and Francis}, organization = {CRC Press - Taylor and Francis}, author = {Fabio Sterpone and Simone Melchionna}, editor = {Srikanta Sen and Lennart Nilsson} } @article {2010|1685, title = {Non adiabatic simulations of exciton dissociation in poly-p-phenylenevinylene oligomers}, journal = {J. Phys. Chem. A}, volume = {114}, year = {2010}, pages = {7661{\textendash}7670}, author = {M. Bedard-Hearn and Fabio Sterpone and P.J. Rossky} } @article {2010|1445, title = {Water around thermophilic proteins: the role of charged and apolar atoms}, journal = {J Phys: Cond Matt}, volume = {22}, number = {28}, year = {2010}, pages = {284113}, author = {Fabio Sterpone and Claudia Bertonati and Giuseppe Briganti and Simone Melchionna} } @article {2008|1678, title = {Water-water hydrogen bond studied by QMC}, journal = {J. Chem. Theory. Comput.}, volume = {4}, year = {2008}, pages = {1428{\textendash}1432}, author = {Fabio Sterpone and L. Spanu and L. Ferraro and S. Sorella and L. Guidoni} } @article {2004|1718, title = {Temperature dehydration of C12E6 micelle}, journal = {Langmuir}, volume = {20}, year = {2004}, pages = {4311{\textendash}4314}, author = {Fabio Sterpone and C. Pierleoni and G. Briganti and M. Marchi} } @article {2003|1694, title = {Linear response and electron transfer in complex biomolecules systems and Reaction Center Protein}, journal = {J. Phys. Chem. B}, volume = {107}, year = {2003}, pages = {11208{\textendash}11215}, author = {Fabio Sterpone and M. Ceccarelli and M. Marchi} }