@misc{Weber2009, author = {Weber, Marcus}, title = {A Subspace Approach to Molecular Markov State Models via an Infinitesimal Generator}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11432}, number = {09-27}, year = {2009}, abstract = {Supercomputers can simulate complex molecular systems. However, there is a very large gap between the fastest oscillations of covalent bonds of a molecule and the time-scale of the dominant processes. In order to extract the dominant time-scales and to identify the dominant processes, a clustering of information is needed. This thesis shows that only the subspace-based Robust Perron Cluster Analysis (PCCA+) can solve this problem correctly by the construction of a Markov State Model. PCCA+ allows for time-extrapolation in molecular kinetics. This thesis shows the difference between molecular dynamics and molecular kinetics. Only in the molecular kinetics framework a definition of transition rates is possible. In this context, the existence of an infinitesimal generator of the dynamical processes is discussed. If the existence is assumed, the Theorem of Gauß can be applied in order to compute transition rates efficiently. Molecular dynamics, however, is not able to provide a suitable statistical basis for the determination of the transition pattern.}, language = {en} } @misc{FackeldeyRoeblitzScharkoietal.2011, author = {Fackeldey, Konstantin and R{\"o}blitz, Susanna and Scharkoi, Olga and Weber, Marcus}, title = {Soft Versus Hard Metastable Conformations in Molecular Simulations}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-13189}, number = {11-27}, year = {2011}, abstract = {Particle methods have become indispensible in conformation dynamics to compute transition rates in protein folding, binding processes and molecular design, to mention a few. Conformation dynamics requires at a decomposition of a molecule's position space into metastable conformations. In this paper, we show how this decomposition can be obtained via the design of either ``soft'' or ``hard'' molecular conformations. We show, that the soft approach results in a larger metastabilitiy of the decomposition and is thus more advantegous. This is illustrated by a simulation of Alanine Dipeptide.}, language = {en} } @phdthesis{Weber2011, author = {Weber, Marcus}, title = {A Subspace Approach to Molecular Markov State Models via a New Infinitesimal Generator}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-14025}, school = {Zuse Institute Berlin (ZIB)}, year = {2011}, abstract = {Supercomputers can simulate complex molecular systems. However, there is a very large gap between the fastest oscillations of covalent bonds of a molecule and the time-scale of the dominant processes. In order to extract the dominant time-scales and to identify the dominant processes, a clustering of information is needed. This thesis shows that only the subspace-based Robust Perron Cluster Analysis (PCCA+) can solve this problem correctly by the construction of a Markov State Model. PCCA+ allows for time-extrapolation in molecular kinetics. This thesis shows the difference between molecular dynamics and molecular kinetics. Only in the molecular kinetics framework a definition of transition rates is possible. In this context, the existence of an infinitesimal generator of the dynamical processes is discussed. If the existence is assumed, the Theorem of Gauß can be applied in order to compute transition rates efficiently. Molecular dynamics, however, is not able to provide a suitable statistical basis for the determination of the transition pattern.}, language = {en} } @misc{Weber2012, author = {Weber, Marcus}, title = {The funnel trap paradox}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-14765}, number = {12-12}, year = {2012}, abstract = {In this article, an illustrative example is given for the coarse-graining of a Markov process which leads to a shift in the statistical weights of a two-states-system. The example is based on a 2D-funnel trap. The funnel trap is constructed in such a way, that the area inside and outside of the trap is identical. However, observing the flight of the insect as a Markov process, the probability for being "in the trap" is higher. This example can be transferred to several kinds of processes (like receptor-ligandbinding processes in chemistry) and describes the influence of "re-entering events".}, language = {en} } @misc{Fackeldey2010, author = {Fackeldey, Konstantin}, title = {Coupling Meshbased and Meshfree Methods by a Transfer Operator Approach}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-11755}, number = {10-12}, year = {2010}, abstract = {In contrast to the well known meshbased methods like the finite element method, meshfree methods do not rely on a mesh. However besides their great applicability, meshfree methods are rather time consuming. Thus, it seems favorable to combine both methods, by using meshfree methods only in a small part of the domain, where a mesh is disadvantageous, and a meshbased method for the rest of the domain. We motivate, that this coupling between the two simulation techniques can be considered as saddle point problem and show the stability of this coupling. Thereby a novel transfer operator is introduced, which interacts in the transition zone, where both methods coexist.}, language = {en} } @misc{TungaWeber2012, author = {Tunga, Burcu and Weber, Marcus}, title = {Free Energy Calculation Using Mayer Cluster Expansion and Fluctuation Free Integration}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-16031}, year = {2012}, abstract = {This work aims to develop a new algorithm to calculate the free energy of water molecules by using a deterministic way. For this purpose, we assume a closed system confined to a physical volume, having water molecules in gas phase. To calculate the free energy of this sytem we utilized Mayer cluster expansion and the fluctuation free integration method.}, language = {en} } @misc{WeberFackeldey2013, author = {Weber, Marcus and Fackeldey, Konstantin}, title = {Computing the Minimal Rebinding Effect Included in a Given Kinetics}, issn = {1438-0064}, doi = {10.1137/13091124X}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-17796}, year = {2013}, abstract = {The rebinding effect is a phenomenon which occurs when observing a ligand-receptor binding process. On the macro scale this process comprises the Markov property. This Makovian view is spoiled when switching to the atomistic scale of a binding process. We therefore suggest a model which accurately describes the rebinding effect on the atomistic scale by allowing ''intermediate'' bound states. This allows us to define an indicator for the magnitude of rebinding and to formulate an optimization problem. The results form our examples show good agreement with data form laboratory.}, language = {en} } @misc{LieFackeldeyWeber2013, author = {Lie, Han Cheng and Fackeldey, Konstantin and Weber, Marcus}, title = {A square root approximation of transition rates for a Markov State Model}, issn = {1438-0064}, doi = {10.1137/120899959}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-42195}, year = {2013}, abstract = {Trajectory- or mesh-based methods for analyzing the dynamical behavior of large molecules tend to be impractical due to the curse of dimensionality - their computational cost increases exponentially with the size of the molecule. We propose a method to break the curse by a novel square root approximation of transition rates, Monte Carlo quadrature and a discretization approach based on solving linear programs. With randomly sampled points on the molecular energy landscape and randomly generated discretizations of the molecular configuration space as our initial data, we construct a matrix describing the transition rates between adjacent discretization regions. This transition rate matrix yields a Markov State Model of the molecular dynamics. We use Perron cluster analysis and coarse-graining techniques in order to identify metastable sets in configuration space and approximate the transition rates between the metastable sets. Application of our method to a simple energy landscape on a two-dimensional configuration space provides proof of concept and an example for which we compare the performance of different discretizations. We show that the computational cost of our method grows only polynomially with the size of the molecule. However, finding discretizations of higher-dimensional configuration spaces in which metastable sets can be identified remains a challenge.}, language = {en} } @misc{NielsenFackeldeyWeber2013, author = {Nielsen, Adam and Fackeldey, Konstantin and Weber, Marcus}, title = {On a Generalized Transfer Operator}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-43162}, year = {2013}, abstract = {We introduce a generalized operator for arbitrary stochastic processes by using a pre-kernel, which is a generalization of the Markov kernel. For deterministic processes, such an operator is already known as the Frobenius-Perron operator, which is defined for a large class of measures. For Markov processes, there exists transfer operators being only well defined for stationary measures in \$L^2\$. Our novel generalized transfer operator is well defined for arbitrary stochastic processes, in particular also for deterministic ones. We can show that this operator is acting on \$L^1\$. For stationary measures, this operator is also an endomorphism of \$L^2\$ and, therefore, allows for a mathematical analysis in Hilbert spaces.}, language = {en} } @article{FackeldeyKoltaiNeviretal.2019, author = {Fackeldey, Konstantin and Koltai, Peter and Nevir, Peter and Rust, Henning and Schild, Axel and Weber, Marcus}, title = {From metastable to coherent sets - Time-discretization schemes}, volume = {29}, journal = {Chaos: An Interdisciplinary Journal of Nonlinear Science}, doi = {10.1063/1.5058128}, pages = {012101 -- 012101}, year = {2019}, abstract = {In this article, we show that these well-established spectral algorithms (like PCCA+, Perron Cluster Cluster Analysis) also identify coherent sets of non-autonomous dynamical systems. For the identification of coherent sets, one has to compute a discretization (a matrix T) of the transfer operator of the process using a space-time-discretization scheme. The article gives an overview about different time-discretization schemes and shows their applicability in two different fields of application.}, language = {en} } @article{AbbasSchneiderBollmannetal.2019, author = {Abbas, Aennes and Schneider, Ilona and Bollmann, Anna and Funke, Jan and Oehlmann, J{\"o}rg and Prasse, Carsten and Schulte-Oehlmann, Ulrike and Seitz, Wolfram and Ternes, Thomas and Weber, Marcus and Wesely, Henning and Wagner, Martin}, title = {What you extract is what you see: Optimising the preparation of water and wastewater samples for in vitro bioassays}, volume = {152}, journal = {Water Research}, doi = {10.1016/j.watres.2018.12.049}, pages = {47 -- 60}, year = {2019}, abstract = {The assessment of water quality is crucial for safeguarding drinking water resources and ecosystem integrity. To this end, sample preparation and extraction is critically important, especially when investigating emerging contaminants and the toxicity of water samples. As extraction methods are rarely optimised for bioassays but rather adopted from chemical analysis, this may result in a misrepresentation of the actual toxicity. In this study, surface water, groundwater, hospital and municipal wastewater were used to characterise the impacts of common sample preparation techniques (acidification, filtration and solid phase extraction (SPE)) on the outcomes of eleven in vitro bioassays. The latter covered endocrine activity (reporter gene assays for estrogen, androgen, aryl-hydrocarbon, retinoic acid, retinoid X, vitamin D, thyroid receptor), mutagenicity (Ames fluctuation test), genotoxicity (umu test) and cytotoxicity. Water samples extracted using different SPE sorbents (Oasis HLB, Supelco ENVI-Carb+, Telos C18/ENV) at acidic and neutral pH were compared for their performance in recovering biological effects. Acidification, commonly used for stabilisation, significantly altered the endocrine activity and toxicity of most (waste)water samples. Sample filtration did not affect the majority of endpoints but in certain cases affected the (anti-)estrogenic and dioxin-like activities. SPE extracts (10.4 × final concentration), including WWTP effluents, induced significant endocrine effects that were not detected in aqueous samples (0.63 × final concentration), such as estrogenic, (anti-)androgenic and dioxin-like activities. When ranking the SPE methods using multivariate Pareto optimisation an extraction with Telos C18/ENV at pH 7 was most effective in recovering toxicity. At the same time, these extracts were highly cytotoxic masking the endpoint under investigation. Compared to that, extraction at pH 2.5 enriched less cytotoxicity. In summary, our study demonstrates that sample preparation and extraction critically affect the outcome of bioassays when assessing the toxicity of water samples. Depending on the water matrix and the bioassay, these methods need to be optimised to accurately assess water quality.}, language = {en} } @misc{Helfmann2018, type = {Master Thesis}, author = {Helfmann, Luzie}, title = {Stochastic Modeling of Interacting Agent Systems}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-71887}, pages = {68}, year = {2018}, language = {en} } @article{ReuterFackeldeyWeber2019, author = {Reuter, Bernhard and Fackeldey, Konstantin and Weber, Marcus}, title = {Generalized Markov modeling of nonreversible molecular kinetics}, volume = {17}, journal = {The Journal of Chemical Physics}, number = {150}, doi = {10.1063/1.5064530}, pages = {174103}, year = {2019}, abstract = {Markov state models are to date the gold standard for modeling molecular kinetics since they enable the identification and analysis of metastable states and related kinetics in a very instructive manner. The state-of-the-art Markov state modeling methods and tools are very well developed for the modeling of reversible processes in closed equilibrium systems. On the contrary, they are largely not well suited to deal with nonreversible or even nonautonomous processes of nonequilibrium systems. Thus, we generalized the common Robust Perron Cluster Cluster Analysis (PCCA+) method to enable straightforward modeling of nonequilibrium systems as well. The resulting Generalized PCCA (G-PCCA) method readily handles equilibrium as well as nonequilibrium data by utilizing real Schur vectors instead of eigenvectors. This is implemented in the G-PCCA algorithm that enables the semiautomatic coarse graining of molecular kinetics. G-PCCA is not limited to the detection of metastable states but also enables the identification and modeling of cyclic processes. This is demonstrated by three typical examples of nonreversible systems.}, language = {en} } @article{ErnstFackeldeyVolkameretal.2019, author = {Ernst, Natalia and Fackeldey, Konstantin and Volkamer, Andrea and Opatz, Oliver and Weber, Marcus}, title = {Computation of temperature-dependent dissociation rates of metastable protein-ligand complexes}, volume = {45}, journal = {Molecular Simulation}, number = {11}, doi = {10.1080/08927022.2019.1610949}, pages = {904 -- 911}, year = {2019}, abstract = {Molecular simulations are often used to analyse the stability of protein-ligand complexes. The stability can be characterised by exit rates or using the exit time approach, i.e. by computing the expected holding time of the complex before its dissociation. However determining exit rates by straightforward molecular dynamics methods can be challenging for stochastic processes in which the exit event occurs very rarely. Finding a low variance procedure for collecting rare event statistics is still an open problem. In this work we discuss a novel method for computing exit rates which uses results of Robust Perron Cluster Analysis (PCCA+). This clustering method gives the possibility to define a fuzzy set by a membership function, which provides additional information of the kind 'the process is being about to leave the set'. Thus, the derived approach is not based on the exit event occurrence and, therefore, is also applicable in case of rare events. The novel method can be used to analyse the temperature effect of protein-ligand systems through the differences in exit rates, and, thus, open up new drug design strategies and therapeutic applications.}, language = {en} } @article{VillatoroWeberZuehlkeetal.2019, author = {Villatoro, Jos{\´e} and Weber, Marcus and Z{\"u}hlke, Martin and Lehmann, Andreas and Zechiowski, Karl and Riebe, Daniel and Beitz, Toralf and L{\"o}hmannsr{\"o}ben, Hans-Gerd and Kreuzer, Oliver}, title = {Structural characterization of synthetic peptides using electronspray ion mobility spectrometry and molecular dynamics simulations}, volume = {436}, journal = {International Journal of Mass Spectrometry}, doi = {10.1016/j.ijms.2018.10.036}, pages = {108 -- 117}, year = {2019}, abstract = {Electrospray ionization-ion mobility spectrometry was employed for the determination of collision cross sections (CCS) of 25 synthetically produced peptides in the mass range between 540-3310 Da. The experimental measurement of the CCS is complemented by their calculation applying two different methods. One prediction method is the intrinsic size parameter (ISP) method developed by the Clemmer group. The second new method is based on the evaluation of molecular dynamics (MD) simulation trajectories as a whole, resulting in a single, averaged collision cross-section value for a given peptide in the gas phase. A high temperature MD simulation is run in order to scan through the whole conformational space. The lower temperature conformational distribution is obtained through thermodynamic reweighting. In the first part, various correlations, e.g. CCS vs. mass and inverse mobility vs. m/z correlations, are presented. Differences in CCS between peptides are also discussed in terms of their respective mass and m/z differences, as well as their respective structures. In the second part, measured and calculated CCS are compared. The agreement between the prediction results and the experimental values is in the same range for both calculation methods. While the calculation effort of the ISP method is much lower, the MD method comprises several tools providing deeper insights into the conformations of peptides. Advantages and limitations of both methods are discussed. Based on the separation of two pairs of linear and cyclic peptides of virtually the same mass, the influence of the structure on the cross sections is discussed. The shift in cross section differences and peak shape after transition from the linear to the cyclic peptide can be well understood by applying different MD tools, e.g. the root-mean-square deviation (RMSD) and the root mean square fluctuation (RMSF).}, language = {en} } @phdthesis{Reuter2018, author = {Reuter, Bernhard}, title = {Generalisierte Markov-Modellierung von Nichtgleichgewichtssystemen - Simulation und Modellierung der Amyloid-beta(1-40)-Konformationsdynamik unter Mikrowelleneinfluss}, year = {2018}, language = {de} } @phdthesis{Quer2018, author = {Quer, Jannes}, title = {Importance Sampling for metastable dynamical systems in molecular dynamics}, year = {2018}, language = {en} } @phdthesis{Klimm2018, author = {Klimm, Martina}, title = {New Strategies in Conformation Dynamics}, year = {2018}, language = {en} } @phdthesis{Villatoro2018, author = {Villatoro, Jos{\´e}}, title = {A combined approach for the analysis of biomolecules using IR-MALDI ion mobility spectrometry and molecular dynamics simulations of peptide ions in the gas phase}, year = {2018}, language = {en} } @article{ReidelbachWeberImhof2018, author = {Reidelbach, Marco and Weber, Marcus and Imhof, Petra}, title = {Prediction of perturbed proton transfer networks}, volume = {13}, journal = {PLoS ONE}, number = {12}, doi = {https://doi.org/10.1371/journal.pone.0207718}, pages = {e0207718 -- e0207718}, year = {2018}, abstract = {The transfer of protons through proton translocating channels is a complex process, for which direct samplings of different protonation states and side chain conformations in a transition network calculation provide an efficient, bias-free description. In principle, a new transition network calculation is required for every unsampled change in the system of interest, e.g. an unsampled protonation state change, which is associated with significant computational costs. Transition networks void of or including an unsampled change are termed unperturbed or perturbed, respectively. Here, we present a prediction method, which is based on an extensive coarse-graining of the underlying transition networks to speed up the calculations. It uses the minimum spanning tree and a corresponding sensitivity analysis of an unperturbed transition network as initial guess and refinement parameter for the determination of an unknown, perturbed transition network. Thereby, the minimum spanning tree defines a sub-network connecting all nodes without cycles and minimal edge weight sum, while the sensitivity analysis analyzes the stability of the minimum spanning tree towards individual edge weight reductions. Using the prediction method, we are able to reduce the calculation costs in a model system by up to 80\%, while important network properties are maintained in most predictions.}, language = {en} } @article{LieFackeldeyWeber2013, author = {Lie, Han Cheng and Fackeldey, Konstantin and Weber, Marcus}, title = {A Square Root Approximation of Transition Rates for a Markov State Model}, volume = {34}, journal = {SIAM. J. Matrix Anal. Appl.}, number = {2}, doi = {10.1137/120899959}, pages = {738 -- 756}, year = {2013}, language = {en} } @article{ScharkoiFackeldeyMerkulowetal.2013, author = {Scharkoi, Olga and Fackeldey, Konstantin and Merkulow, Igor and Andrae, Karsten and Weber, Marcus and Nehls, Irene}, title = {Conformational Analysis of Alternariol on the Quantum Level}, volume = {19}, journal = {J. Mol. Model.}, number = {6}, doi = {10.1007/s00894-013-1803-2}, pages = {2567 -- 2572}, year = {2013}, language = {en} } @misc{BujotzekSchuettNielsenetal.2013, author = {Bujotzek, Alexander and Sch{\"u}tt, Ole and Nielsen, Adam and Fackeldey, Konstantin and Weber, Marcus}, title = {Efficient Conformational Analysis by Partition-of-Unity Coupling}, journal = {Math Chem}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-42570}, year = {2013}, abstract = {Obtaining a sufficient sampling of conformational space is a common problem in molecular simulation. We present the implementation of an umbrella-like adaptive sampling approach based on function-based meshless discretization of conformational space that is compatible with state of the art molecular dynamics code and that integrates an eigenvector-based clustering approach for conformational analysis and the computation of inter-conformational transition rates. The approach is applied to three example systems, namely n-pentane, alanine dipeptide, and a small synthetic host-guest system, the latter two including explicitly modeled solvent.}, language = {en} } @article{SpahnDelVecchioLabuzetal.2017, author = {Spahn, Viola and Del Vecchio, Giovanna and Labuz, Dominika and Rodriguez-Gaztelumendi, Antonio and Massaly, N. and Temp, Julia and Durmaz, Vedat and Sabri, P. and Reidelbach, Marco and Machelska, Halina and Weber, Marcus and Stein, Christoph}, title = {A nontoxic pain killer designed by modeling of pathological receptor conformations}, volume = {355}, journal = {Science}, number = {6328}, doi = {10.1126/science.aai8636}, pages = {966 -- 969}, year = {2017}, language = {en} } @misc{Weber2017, author = {Weber, Marcus}, title = {Eigenvalues of non-reversible Markov chains - A case study}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-62191}, year = {2017}, abstract = {Finite reversible Markov chains are characterized by a transition matrix P that has real eigenvalues and pi-orthogonal eigenvectors, where pi is the stationary distribution of P. This means, that a transition matrix with complex eigenvalues corresponds to a non-reversible Markov chain. This observation leads to the question, whether the imaginary part of that eigendecomposition corresponds to or indicates the "pattern" of the nonreversibility. This article shows that the direct relation between imaginary parts of eigendecompositions and the non-reversibility of a transition matrix is not given. It is proposed to apply the Schur decomposition of P instead of the eigendecomposition in order to characterize its nonreversibility.}, language = {en} } @article{HartmannSchuetteWeberetal.2017, author = {Hartmann, Carsten and Sch{\"u}tte, Christof and Weber, Marcus and Zhang, Wei}, title = {Importance sampling in path space for diffusion processes with slow-fast variables}, journal = {Probability Theory and Related Fields}, doi = {10.1007/s00440-017-0755-3}, pages = {1 -- 52}, year = {2017}, abstract = {Importance sampling is a widely used technique to reduce the variance of a Monte Carlo estimator by an appropriate change of measure. In this work, we study importance sampling in the framework of diffusion process and consider the change of measure which is realized by adding a control force to the original dynamics. For certain exponential type expectation, the corresponding control force of the optimal change of measure leads to a zero-variance estimator and is related to the solution of a Hamilton-Jacobi-Bellmann equation. We focus on certain diffusions with both slow and fast variables, and the main result is that we obtain an upper bound of the relative error for the importance sampling estimators with control obtained from the limiting dynamics. We demonstrate our approximation strategy with an illustrative numerical example.}, language = {en} } @article{VillatoroZuehlkeRiebeetal.2016, author = {Villatoro, Jos{\´e} and Z{\"u}hlke, Martin and Riebe, Daniel and Beitz, Toralf and Weber, Marcus and Riedel, Jens and L{\"o}hmannsr{\"o}ben, Hans-Gerd}, title = {IR-MALDI ion mobility spectrometry: physical source characterization and application as HPLC detector}, journal = {International Journal for Ion Mobility Spectrometry}, number = {19/4}, doi = {10.1007/s12127-016-0208-1}, pages = {197 -- 297}, year = {2016}, language = {en} } @article{GuerlerMollWeberetal.2008, author = {Guerler, A. and Moll, Sebastian and Weber, Marcus and Meyer, Holger and Cordes, Frank}, title = {Selection and flexible optimization of binding modes from conformation ensembles}, volume = {92}, journal = {Biosystems}, number = {1}, doi = {DOI: 10.1016/j.biosystems.2007.11.004}, pages = {42 -- 48}, year = {2008}, language = {en} } @misc{Guerler2006, type = {Master Thesis}, author = {G{\"u}rler, A.}, title = {Selection and flexible optimization of binding modes from conformation ensembles.}, year = {2006}, language = {en} } @article{HaackRoeblitzScharkoietal.2010, author = {Haack, Fiete and R{\"o}blitz, Susanna and Scharkoi, Olga and Schmidt, Burkhard and Weber, Marcus}, title = {Adaptive Spectral Clustering for Conformation Analysis}, volume = {1281}, journal = {AIP Conference Proceedings}, number = {1}, publisher = {AIP}, doi = {10.1063/1.3498116}, pages = {1585 -- 1588}, year = {2010}, language = {en} } @incollection{DurmazFackeldeyWeber2011, author = {Durmaz, Vedat and Fackeldey, Konstantin and Weber, Marcus}, title = {A rapidly Mixing Monte Carlo Method for the Simulation of Slow Molecular Processes}, booktitle = {Applications of Monte Carlo Methods in Biology, Medicine and Other Fields of Science}, editor = {Mode, Ch.}, publisher = {InTech}, year = {2011}, language = {en} } @inproceedings{FackeldeyKrauseKrause2008, author = {Fackeldey, Konstantin and Krause, Dorian and Krause, Rolf}, title = {Quadrature and Implementation of the Weak Coupling Method}, booktitle = {MMM 2008: Proceedings of the 4th International Conference on Multiscale Materials Modelling, 27-31 October 2008, Tallahassee, Fla.}, pages = {62 -- 65}, year = {2008}, language = {en} } @inproceedings{FackeldeyKrauseKrause2009, author = {Fackeldey, Konstantin and Krause, Dorian and Krause, Rolf}, title = {Weak Coupling Algorithms in Multiscale Simulations}, booktitle = {Proceedings of the third Inter. Confer. on Comp. Meth. for Coupled Problems in Science and Engrg}, pages = {1023pp}, year = {2009}, language = {en} } @inproceedings{FackeldeyKrauseKrause2010, author = {Fackeldey, Konstantin and Krause, Dorian and Krause, Rolf}, title = {Numerical Validation of Constraints Based Multiscale Methods}, booktitle = {Lecture Notes in Computational Science and Engineering}, editor = {Griebel, Michael and Schweitzer, M.}, pages = {141 -- 154}, year = {2010}, language = {en} } @article{FackeldeyKrauseKrauseetal.2011, author = {Fackeldey, Konstantin and Krause, Dorian and Krause, Rolf and Lenzen, Christoph}, title = {Coupling Molecular Dynamics and Continua with Weak Constraints}, volume = {9}, journal = {SIAM Multiscale Model. Simul.}, doi = {/10.1137/100782097}, pages = {1459 -- 1494}, year = {2011}, language = {en} } @inproceedings{FackeldeyKrauseSchweitzer2008, author = {Fackeldey, Konstantin and Krause, Rolf and Schweitzer, M.}, title = {Stability of Energy Transfer in the Weak Coupling Method}, volume = {65}, booktitle = {Meshfree Methods for Partial Differential Equations IV}, editor = {Griebel, Michael and Schweitzer, M.}, pages = {111 -- 121}, year = {2008}, language = {en} } @article{Fackeldey2011, author = {Fackeldey, Konstantin}, title = {Coupling Meshbased and Meshfree Methods by a Transfer Operator Approach}, volume = {69}, journal = {IJPAM}, number = {2}, pages = {185 -- 202}, year = {2011}, language = {en} } @article{FischerCordesSchuette1998, author = {Fischer, Alexander and Cordes, Frank and Sch{\"u}tte, Christof}, title = {Hybrid Monte Carlo with Adaptive Temperature in Mixed-Canonical Ensemble: Efficient conformational analysis of RNA}, volume = {19}, journal = {J. Comp. Chem.}, number = {15}, doi = {10.1002/(SICI)1096-987X(19981130)19:15<1689::AID-JCC2>3.0.CO;2-J}, pages = {1689 -- 1697}, year = {1998}, language = {en} } @article{FackeldeyKrause2009, author = {Fackeldey, Konstantin and Krause, Rolf}, title = {Multiscale Coupling in Function Space - Weak Coupling between Molecular Dynamics and Continuum Mechanics}, volume = {79}, journal = {International Journal for Numerical Methods in Engineering}, number = {12}, doi = {10.1002/nme.2626}, pages = {1517 -- 1535}, year = {2009}, language = {en} } @phdthesis{Fackeldey2009, author = {Fackeldey, Konstantin}, title = {The Weak Coupling Method for Coupling Continuum Mechanics with Molecular Dynamics}, year = {2009}, language = {en} } @inproceedings{FackeldeyKrause2007, author = {Fackeldey, Konstantin and Krause, Rolf}, title = {Solving Frictional Contact Problems with Multigrid Efficiency}, volume = {50}, booktitle = {Proc.of the 16th International Conference on Domain Decomposition Methods}, editor = {Widlund, Olof}, pages = {547 -- 554}, year = {2007}, language = {en} } @inproceedings{FackeldeyKrause2007, author = {Fackeldey, Konstantin and Krause, Rolf}, title = {Weak coupling in function space}, volume = {7}, booktitle = {Proc. Appl. Math. Mech.}, number = {1}, pages = {2020113pp}, year = {2007}, language = {en} } @inproceedings{FackeldeyKrause2008, author = {Fackeldey, Konstantin and Krause, Rolf}, title = {CM/MD Coupling - A Function Space Oriented Multiscale-Coupling Approach}, volume = {8}, booktitle = {Proc. Appl. Math. Mech.}, number = {1}, pages = {10495pp}, year = {2008}, language = {en} } @article{GuerlerMollWeberetal.2007, author = {G{\"u}rler, A. and Moll, Sebastian and Weber, Marcus and Meyer, Holger and Cordes, Frank}, title = {Selection and flexible optimization of binding modes from conformation ensembles}, journal = {Biosystems}, year = {2007}, language = {en} } @article{KubeWeber2007, author = {Kube, Susanna and Weber, Marcus}, title = {A Coarse Graining Method for the Identification of Transition rates between Molecular Conformations}, volume = {126}, journal = {Journal of Chemical Physics}, number = {2}, doi = {10.1063/1.2404953}, year = {2007}, language = {en} } @article{KuemmelAndraeReinhard2001, author = {K{\"u}mmel, S. and Andrae, Karsten and Reinhard, P.-G.}, title = {Collectivity in the optical response. of small metal clusters}, volume = {73}, journal = {Applied Physics B}, number = {4}, publisher = {Springer Berlin / Heidelberg}, pages = {293 -- 297}, year = {2001}, language = {en} } @article{LasserRoeblitz2010, author = {Lasser, Caroline and R{\"o}blitz, Susanna}, title = {Computing expectation values for molecular quantum dynamics}, volume = {32}, journal = {SIAM Journal on Scientific Computing}, number = {3}, doi = {/10.1137/090770461}, pages = {1465 -- 1483}, year = {2010}, language = {en} } @inproceedings{WeberKube2005, author = {Weber, Marcus and Kube, Susanna}, title = {Robust Perron Cluster Analysis for Various Applications in Computational Life Science}, booktitle = {Computational Life Sciences}, pages = {57 -- 66}, year = {2005}, language = {en} } @article{MetznerWeberSchuette2010, author = {Metzner, Ph. and Weber, Marcus and Sch{\"u}tte, Christof}, title = {Observation uncertainty in reversible Markov chains}, volume = {82}, journal = {Phys. Rev. E}, number = {3}, publisher = {American Physical Society}, doi = {10.1103/PhysRevE.82.031114}, pages = {031114}, year = {2010}, language = {en} } @article{KlimmBujotzekWeber2011, author = {Klimm, Martina and Bujotzek, Alexander and Weber, Marcus}, title = {Direct Reweighting Strategies in Conformation Dynamics}, volume = {65(2)}, journal = {MATCH Commun. Math. Comp. Chem.}, pages = {333 -- 346}, year = {2011}, language = {en} } @inproceedings{KubeWeber2008, author = {Kube, Susanna and Weber, Marcus}, title = {Computation of equilibrium densities in metastable dynamical systems by domain decomposition}, volume = {1048}, booktitle = {Numerical Analysis and Applied Mathematics, International Conference on Numerical Analysis and Applied Mathematics 2008}, publisher = {AIP Conference Proceedings}, pages = {339 -- 342}, year = {2008}, language = {en} } @masterthesis{Scharkoi2007, type = {Bachelor Thesis}, author = {Scharkoi, O.}, title = {Simulation von Opioiden unter Hinzunahme von Temperatur und pH-Wert}, year = {2007}, language = {en} } @article{ScheibeBujotzekDerneddeetal.2011, author = {Scheibe, Ch. and Bujotzek, Alexander and Dernedde, Jens and Weber, Marcus and Seitz, O.}, title = {DNA-programmed spatial screening of carbohydrate-lectin interactions}, volume = {2}, journal = {Chem. Sci.}, pages = {770 -- 775}, year = {2011}, language = {en} } @article{SiegelAndraeProskeetal.2010, author = {Siegel, D. and Andrae, Karsten and Proske, Matthias and Kochan, C. and Koch, Matthias and Weber, Marcus and Nehls, Irene}, title = {Dynamic covalent hydrazine chemistry as a specific extraction and cleanup technique for the quantification of the Fusarium mycotoxin zearalenone in edible oils}, volume = {1217(15)}, journal = {Journal of Chromatography A}, pages = {2206 -- 15}, year = {2010}, language = {en} } @misc{Riemer2006, type = {Master Thesis}, author = {Riemer, Alexander}, title = {Accuracy, stability, convergence of rigorous thermodynamic sampling methods}, year = {2006}, language = {en} } @inproceedings{ReineckeDeuflhard2008, author = {Reinecke, Isabel and Deuflhard, Peter}, title = {Model Development and Decomposition in Physiology}, volume = {2}, booktitle = {Handbook of Research on Systems Biology Applications in Medicine}, editor = {Daskalaki, A.}, pages = {759 -- 797}, year = {2008}, language = {en} } @article{ReineckeDeuflhard2007, author = {Reinecke, Isabel and Deuflhard, Peter}, title = {A Complex Mathematical Model of the Human Menstrual Cycle}, volume = {247}, journal = {Journal of Theoretical Biology}, number = {2}, pages = {303 -- 330}, year = {2007}, language = {en} } @phdthesis{Weber2006, author = {Weber, Marcus}, title = {Meshless Methods in Conformation Dynamics}, year = {2006}, language = {en} } @incollection{WeberRungsarityotinSchliep2006, author = {Weber, Marcus and Rungsarityotin, Wasinee and Schliep, Alexander}, title = {An Indicator for the Number of Clusters}, booktitle = {From Data and Information Analysis to Knowledge Engineering}, editor = {Spiliopoulou, Myra and Kruse, Rudolf and Borgelt, Christian and N{\"u}rnberger, Andreas and Gaul, Wolfgang}, publisher = {Springer Berlin Heidelberg}, pages = {103 -- 110}, year = {2006}, language = {en} } @article{WeberAndrae2010, author = {Weber, Marcus and Andrae, Karsten}, title = {A simple method for the estimation of entropy differences}, volume = {63(2)}, journal = {MATCH Commun. Math. Comp. Chem. 2010}, pages = {319 -- 332}, year = {2010}, language = {en} } @article{WeberBeckerKoeppenetal.2008, author = {Weber, Marcus and Becker, Roland and K{\"o}ppen, Robert and Durmaz, Vedat}, title = {Classical hybrid Monte-Carlo simulations of the interconversion of hexabromocyclododecane}, volume = {34}, journal = {Journal of Molecular Simulation}, number = {7}, pages = {727 -- 736}, year = {2008}, language = {en} } @article{WeberBujotzekAndraeetal.2011, author = {Weber, Marcus and Bujotzek, Alexander and Andrae, Karsten and Weinhart, M. and Haag, Rainer}, title = {Computational entropy estimation of linear polyether modified surfaces and correlation with protein resistant properties of such surfaces}, journal = {J. Mol. Sim.}, year = {2011}, language = {en} } @article{FoersterBrauerFuersteetal.2007, author = {F{\"o}rster, C. and Brauer, Arnd B. E. and F{\"u}rste, J. and Betzel, C. and Weber, Marcus and Cordes, Frank and Erdmann, V.}, title = {Visualization of the tRNA(Ser) acceptor step binding site in the seryl-tRNA synthetase}, volume = {362}, journal = {BBRC}, number = {2}, pages = {415 -- 418}, year = {2007}, language = {en} } @inproceedings{KubeWeber2008, author = {Kube, Susanna and Weber, Marcus}, title = {Preserving the Markov Property of Reduced Reversible Markov Chains}, volume = {1048}, booktitle = {Numerical Analysis and Applied Mathematics, International Conference on Numerical Analysis and Applied Mathematics 2008}, pages = {593 -- 596}, year = {2008}, language = {en} } @article{WeberKubeWalteretal.2007, author = {Weber, Marcus and Kube, Susanna and Walter, Lionel and Deuflhard, Peter}, title = {Stable Computation of Probability Densities of Metastable Dynamical Systems}, volume = {6}, journal = {SIAM J. Multiscale Model. Simul.}, number = {2}, pages = {396 -- 416}, year = {2007}, language = {en} } @article{KoeppenRiedelProskeetal.2012, author = {K{\"o}ppen, Robert and Riedel, Juliane and Proske, Matthias and Drzymala, Sarah and Rasenko, Tatjana and Durmaz, Vedat and Weber, Marcus and Koch, Matthias}, title = {Photochemical trans-/cis-isomerization and quantification of zearalenone in edible oils}, volume = {60}, journal = {J. Agric. Food Chem.}, doi = {10.1021/jf3037775}, pages = {11733 -- 11740}, year = {2012}, language = {en} } @article{DurmazWeberBecker2012, author = {Durmaz, Vedat and Weber, Marcus and Becker, Roland}, title = {How to Simulate Affinities for Host-Guest Systems Lacking Binding Mode Information: application to the liquid chromatographic separation of hexabromocyclododecane stereoisomers}, volume = {18}, journal = {Journal of Molecular Modeling}, doi = {10.1007/s00894-011-1239-5}, pages = {2399 -- 2408}, year = {2012}, language = {en} } @article{WeberBujotzekHaag2012, author = {Weber, Marcus and Bujotzek, Alexander and Haag, Rainer}, title = {Quantifying the rebinding effect in multivalent chemical ligand-receptor systems}, volume = {137}, journal = {J. Chem. Phys.}, number = {5}, pages = {054111}, year = {2012}, language = {en} } @inproceedings{FackeldeyBujotzekWeber2012, author = {Fackeldey, Konstantin and Bujotzek, Alexander and Weber, Marcus}, title = {A meshless discretization method for Markov state models applied to explicit water peptide folding simulations}, volume = {89}, booktitle = {Meshfree Methods for Partial Differential Equations VI}, publisher = {Springer}, pages = {141 -- 154}, year = {2012}, language = {en} } @article{FastingSchalleyWeberetal.2012, author = {Fasting, Carlo and Schalley, Christoph A. and Weber, Marcus and Seitz, Oliver and Hecht, Stefan and Koksch, Beate and Dernedde, Jens and Graf, Christina and Knapp, Ernst-Walter and Haag, Rainer}, title = {Multivalency as a Chemical Organization and Action Principle}, volume = {51}, journal = {Angew. Chem. Int. Ed.}, number = {42}, pages = {10472 -- 10498}, year = {2012}, language = {en} } @article{DeuflhardHuisingaJahnkeetal.2008, author = {Deuflhard, Peter and Huisinga, Wilhelm and Jahnke, Tobias and Wulkow, Michael}, title = {Adaptive Discrete Galerkin Methods Applied to the Chemical Master Equation}, volume = {30}, journal = {SIAM J. Sci. Comput}, number = {6}, pages = {2990 -- 3011}, year = {2008}, language = {en} } @article{KubeLasserWeber2008, author = {Kube, Susanna and Lasser, Caroline and Weber, Marcus}, title = {Monte Carlo sampling of Wigner functions and surface hopping quantum dynamics}, volume = {228}, journal = {Journal of Computational Physics}, number = {6}, doi = {10.1016/j.jcp.2008.11.016}, pages = {1947 -- 1962}, year = {2008}, language = {en} } @misc{KellermannWeberBujotzek2007, author = {Kellermann, R. and Weber, Marcus and Bujotzek, Alexander}, title = {Vom Dietrich zum Sicherheitsschl{\"u}ssel - Mathematiker des Matheon simulieren neuen Wirkstoff f{\"u}r die Diabetes-Behandlung}, number = {2}, publisher = {DFG-Forschungszentrum Matheon}, year = {2007}, language = {en} } @article{KoeppenBeckerWeberetal.2009, author = {K{\"o}ppen, Robert and Becker, Roland and Weber, Marcus and Durmaz, Vedat and Nehls, Irene}, title = {HBCD stereoisimers: Thermal interconversion and enantiospecific trace analysis in biota}, volume = {70}, journal = {Organohalogen Compounds}, pages = {910 -- 913}, year = {2009}, language = {en} } @article{BujotzekWeber2009, author = {Bujotzek, Alexander and Weber, Marcus}, title = {Efficient Simulation of Ligand-Receptor Binding Processes Using the Conformation Dynamics Approach}, volume = {7(5)}, journal = {Journal of Bioinformatics and Computational Biology}, pages = {811 -- 831}, year = {2009}, language = {en} } @incollection{Weber2009, author = {Weber, Marcus}, title = {Spurenstoffe im Trinkwasser - Risikoqualifizierung im Rechner?}, booktitle = {Schriftenreihe des Vereins f{\"u}r Wasser-, Boden- und Lufthygiene}, editor = {Dunemann, L. and Schmoll, O.}, year = {2009}, language = {en} } @article{WeberDurmazBeckeretal.2009, author = {Weber, Marcus and Durmaz, Vedat and Becker, Roland and Esslinger, Susanne}, title = {Predictive Identification of Pentabromocyclododecane (PBCD) Isomers with high Binding Affinity to hTTR}, volume = {71}, journal = {Organohalogen Compounds}, pages = {247 -- 252}, year = {2009}, language = {en} } @misc{Scharkoi2009, type = {Master Thesis}, author = {Scharkoi, O.}, title = {Conformation Dynamics Design of Pain Relief Drugs}, year = {2009}, language = {en} } @misc{Durmaz2009, type = {Master Thesis}, author = {Durmaz, Vedat}, title = {Theoretical Investigations on HBCD and PBCD}, year = {2009}, language = {en} } @inproceedings{Fackeldey2012, author = {Fackeldey, Konstantin}, title = {Multiscale Methods in Time and Space}, volume = {17}, booktitle = {Progress in Industrial Mathematics at ECMI 2010}, pages = {619 -- 626}, year = {2012}, language = {en} } @article{FackeldeyKlimmWeber2012, author = {Fackeldey, Konstantin and Klimm, Martina and Weber, Marcus}, title = {A Coarse Graining Method for the Dimension Reduction of the State Space of Biomolecules}, volume = {5}, journal = {Journal of Mathematical Chemistry}, number = {9}, pages = {2623 -- 2635}, year = {2012}, language = {en} } @article{RoeblitzWeber2009, author = {R{\"o}blitz, Susanna and Weber, Marcus}, title = {Fuzzy Spectral Clustering by PCCA+}, journal = {Classification and Clustering: Models, Software and Applications}, number = {WIAS Report No. 26}, pages = {73 -- 79}, year = {2009}, language = {en} } @misc{Berg2012, type = {Master Thesis}, author = {Berg, Mascha}, title = {Laufzeitoptimierung der Robusten Perron Cluster Analyse (PCCA+)}, year = {2012}, language = {de} } @article{RoeblitzWeber2013, author = {R{\"o}blitz, Susanna and Weber, Marcus}, title = {Fuzzy spectral clustering by PCCA+: application to Markov state models and data classification}, volume = {7}, journal = {Advances in Data Analysis and Classification}, number = {2}, doi = {10.1007/s11634-013-0134-6}, pages = {147 -- 179}, year = {2013}, language = {en} } @article{KrauseFackeldeyKrause2014, author = {Krause, Dorian and Fackeldey, Konstantin and Krause, Rolf}, title = {A Parallel Multiscale Simulation Toolbox for Coupling Molecular Dynamics and Finite Elements}, journal = {Singular Phenomena and Scaling in Mathematical Models}, editor = {Griebel, Michael}, publisher = {Springer International Publishing}, doi = {10.1007/978-3-319-00786-1_14}, pages = {327 -- 346}, year = {2014}, language = {en} } @article{ScharkoiEsslingerBeckeretal.2014, author = {Scharkoi, Olga and Esslinger, Susanne and Becker, Roland and Weber, Marcus and Nehls, Irene}, title = {Predicting sites of cytochrome P450-mediated hydroxylation applied to CYP3A4 and hexabromocyclododecane}, journal = {Molecular Simulation}, doi = {10.1080/08927022.2014.898845}, year = {2014}, language = {en} } @article{HaackFackeldeyRoeblitzetal.2013, author = {Haack, Fiete and Fackeldey, Konstantin and R{\"o}blitz, Susanna and Scharkoi, Olga and Weber, Marcus and Schmidt, Burkhard}, title = {Adaptive spectral clustering with application to tripeptide conformation analysis}, volume = {139}, journal = {The Journal of Chemical Physics}, doi = {10.1063/1.4830409}, pages = {110 -- 194}, year = {2013}, language = {en} } @misc{Nielsen2012, type = {Master Thesis}, author = {Nielsen, Adam}, title = {Von Femtosekunden zu Minuten}, pages = {107}, year = {2012}, language = {de} } @inproceedings{IgdeWoelkRoeblitzetal.2015, author = {Igde, Sinaida and W{\"o}lk, Hendrik and R{\"o}blitz, Susanna and Reidelbach, Marco and Weber, Marcus and Hartmann, Laura}, title = {Identifying Multivalent Binding Kinetics of Precision Glycomacromolecules: A Kinetic Study Using kinITC}, booktitle = {M{\"u}nster Symposium on Cooperative Effects 2015 - SFB 858, at Westf{\"a}lische Wilhelms-Universit{\"a}t M{\"u}nster, 2015}, year = {2015}, abstract = {Multivalent sugar/protein interactions are well-known to proceed through different binding modes 1-5 which in turn can be described by their binding kinetics 3-5. This study provides additional insight into the association and dissociation reaction rates of complex multivalent sugar/protein interactions. Binding kinetics of recently introduced multivalent precision glycomacromolecules 6-8 to Concanavalin A (Con A) were studied by " kinetic Isothermal Titration Calorimetry " (kinITC) 9-11. The effect of multivalency is evaluated by comparing rate constants of glycomacromolecules obtaining the same and different valency of mannose ligands and by variation of the overall backbone properties, such as hydrophilic/ hydrophoboc. In addition, binding kinetics were studied using different conformations of Con A (homodimer vs.-tetramer) and thus a different protein valency. Our results show that precision glycomacromolecule/Con A binding proceeds non-cooperatively. Further, association and dissociation rates are mainly described by intermolecular complex formation. Together with the so-called functional valency, we can discriminate between " bound " and " unbound " states for macroscopic on-and off-rates, even for such complex glycooligomer/protein systems. By comparing e.g. a mono-to a divalent glycomacromolecule for their binding to dimeric Con A, we see a lower dissociation rate for the latter. As both bind monovalently to Con A, this is a strong indication for a statistical rebinding event. Further, there is a strong dependence of multivalent binding kinetics on the ligand density of glycomacromolecules as well as the Con A conformation and thus the overall on-and off-rates.}, language = {en} } @misc{Nielsen2016, author = {Nielsen, Adam}, title = {The Monte Carlo Computation Error of Transition Probabilities}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-59933}, year = {2016}, abstract = {In many applications one is interested to compute transition probabilities of a Markov chain. This can be achieved by using Monte Carlo methods with local or global sampling points. In this article, we analyze the error by the difference in the \$L^2\$ norm between the true transition probabilities and the approximation achieved through a Monte Carlo method. We give a formula for the error for Markov chains with locally computed sampling points. Further, in the case of reversible Markov chains, we will deduce a formula for the error when sampling points are computed globally. We will see that in both cases the error itself can be approximated with Monte Carlo methods. As a consequence of the result, we will derive surprising properties of reversible Markov chains.}, language = {en} } @article{Nielsen2016, author = {Nielsen, Adam}, title = {The Monte Carlo Computation Error of Transition Probabilities}, volume = {118}, journal = {Statistics \& Probability Letters}, publisher = {Elsevier}, doi = {10.1016/j.spl.2016.06.011}, pages = {163 -- 170}, year = {2016}, abstract = {In many applications one is interested to compute transition probabilities of a Markov chain. This can be achieved by using Monte Carlo methods with local or global sampling points. In this article, we analyze the error by the difference in the \$L^2\$ norm between the true transition probabilities and the approximation achieved through a Monte Carlo method. We give a formula for the error for Markov chains with locally computed sampling points. Further, in the case of reversible Markov chains, we will deduce a formula for the error when sampling points are computed globally. We will see that in both cases the error itself can be approximated with Monte Carlo methods. As a consequence of the result, we will derive surprising properties of reversible Markov chains.}, language = {en} } @article{QuerDonatiKelleretal.2018, author = {Quer, Jannes and Donati, Luca and Keller, Bettina and Weber, Marcus}, title = {An automatic adaptive importance sampling algorithm for molecular dynamics in reaction coordinates}, volume = {40}, journal = {SIAM Journal on Scientific Computing}, number = {2}, doi = {10.1137/17m1124772}, pages = {A653 -- A670}, year = {2018}, abstract = {In this article we propose an adaptive importance sampling scheme for dynamical quantities of high dimensional complex systems which are metastable. The main idea of this article is to combine a method coming from Molecular Dynamics Simulation, Metadynamics, with a theorem from stochastic analysis, Girsanov's theorem. The proposed algorithm has two advantages compared to a standard estimator of dynamic quantities: firstly, it is possible to produce estimators with a lower variance and, secondly, we can speed up the sampling. One of the main problems for building importance sampling schemes for metastable systems is to find the metastable region in order to manipulate the potential accordingly. Our method circumvents this problem by using an assimilated version of the Metadynamics algorithm and thus creates a non-equilibrium dynamics which is used to sample the equilibrium quantities.}, language = {en} } @article{Weber2018, author = {Weber, Marcus}, title = {Transformationsprodukte im Kl{\"a}rwerk: Mathematische Ans{\"a}tze der Bewertung}, journal = {KA Korrespondenz Abwasser, Abfall}, year = {2018}, language = {de} } @misc{Breitbach2018, type = {Master Thesis}, author = {Breitbach, Paula}, title = {Molecular Binding Kinetics of CYP P450 by Using the Infinitesimal Generator Approach}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-69076}, year = {2018}, language = {en} } @article{ReuterWeberFackeldeyetal.2018, author = {Reuter, Bernhard and Weber, Marcus and Fackeldey, Konstantin and R{\"o}blitz, Susanna and Garcia, Martin E.}, title = {Generalized Markov State Modeling Method for Nonequilibrium Biomolecular Dynamics: Exemplified on Amyloid β Conformational Dynamics Driven by an Oscillating Electric Field}, volume = {14}, journal = {Journal of Chemical Theory and Computation}, number = {7}, doi = {10.1021/acs.jctc.8b00079}, pages = {3579 -- 3594}, year = {2018}, abstract = {Markov state models (MSMs) have received an unabated increase in popularity in recent years, as they are very well suited for the identification and analysis of metastable states and related kinetics. However, the state-of-the-art Markov state modeling methods and tools enforce the fulfillment of a detailed balance condition, restricting their applicability to equilibrium MSMs. To date, they are unsuitable to deal with general dominant data structures including cyclic processes, which are essentially associated with nonequilibrium systems. To overcome this limitation, we developed a generalization of the common robust Perron Cluster Cluster Analysis (PCCA+) method, termed generalized PCCA (G-PCCA). This method handles equilibrium and nonequilibrium simulation data, utilizing Schur vectors instead of eigenvectors. G-PCCA is not limited to the detection of metastable states but enables the identification of dominant structures in a general sense, unraveling cyclic processes. This is exemplified by application of G-PCCA on nonequilibrium molecular dynamics data of the Amyloid β (1-40) peptide, periodically driven by an oscillating electric field.}, language = {en} } @article{WagnerZapataWanetal.2018, author = {Wagner, Sabine and Zapata, Carlos and Wan, Wei and Gawlitza, Kornelia and Weber, Marcus and Rurack, Knut}, title = {Role of Counterions in Molecularly Imprinted Polymers for Anionic Species}, volume = {34}, journal = {Langmuir}, number = {23}, doi = {10.1021/acs.langmuir.8b00500}, pages = {6963 -- 6975}, year = {2018}, abstract = {Small-molecule oxoanions are often imprinted noncovalently as carboxylates into molecularly imprinted polymers (MIPs), requiring the use of an organic counterion. Popular species are either pentamethylpiperidine (PMP) as a protonatable cation or tetraalkylammonium (TXA) ions as permanent cations. The present work explores the influence of the TXA as a function of their alkyl chain length, from methyl to octyl, using UV/vis absorption, fluorescence titrations, and HPLC as well as MD simulations. Protected phenylalanines (Z-L/D-Phe) served as templates/analytes. While the influence of the counterion on the complex stability constants and anion-induced spectral changes shows a monotonous trend with increasing alkyl chain length at the prepolymerization stage, the cross-imprinting/rebinding studies showed a unique pattern that suggested the presence of adaptive cavities in the MIP matrix, related to the concept of induced fit of enzyme-substrate interaction. Larger cavities formed in the presence of larger counterions can take up pairs of Z-x-Phe and smaller TXA, eventually escaping spectroscopic detection. Correlation of the experimental data with the MD simulations revealed that counterion mobility, the relative distances between the three partners, and the hydrogen bond lifetimes are more decisive for the response features observed than actual distances between interacting atoms in a complex or the orientation of binding moieties. TBA has been found to yield the highest imprinting factor, also showing a unique dual behavior regarding the interaction with template and fluorescent monomer. Finally, interesting differences between both enantiomers have been observed in both theory and experiment, suggesting true control of enantioselectivity. The contribution concludes with suggestions for translating the findings into actual MIP development.}, language = {en} } @article{SpahnDelVecchioRodriguezGaztelumendietal.2018, author = {Spahn, Viola and Del Vecchio, Giovanna and Rodriguez-Gaztelumendi, Antonio and Temp, Julia and Labuz, Dominika and Kloner, Michael and Reidelbach, Marco and Machelska, Halina and Weber, Marcus and Stein, Christoph}, title = {Opioid receptor signaling, analgesic and side effects induced by a computationally designed pH-dependent agonist}, volume = {8}, journal = {Scientific Reports}, publisher = {Springer Nature}, pages = {8965}, year = {2018}, abstract = {Novel pain killers without adverse effects are urgently needed.}, language = {en} } @article{ErlekamIgdeRoeblitzetal.2019, author = {Erlekam, Franziska and Igde, Sinaida and R{\"o}blitz, Susanna and Hartmann, Laura and Weber, Marcus}, title = {Modeling of Multivalent Ligand-Receptor Binding Measured by kinITC}, volume = {7}, journal = {Computation}, number = {3}, doi = {10.3390/computation7030046}, pages = {46}, year = {2019}, abstract = {In addition to the conventional Isothermal Titration Calorimetry (ITC), kinetic ITC (kinITC) not only gains thermodynamic information, but also kinetic data from a biochemical binding process. Moreover, kinITC gives insights into reactions consisting of two separate kinetic steps, such as protein folding or sequential binding processes. The ITC method alone cannot deliver kinetic parameters, especially not for multivalent bindings. This paper describes how to solve the problem using kinITC and an invariant subspace projection. The algorithm is tested for multivalent systems with different valencies.}, language = {en} } @article{Weber2019, author = {Weber, Marcus}, title = {Transformationsprodukte im Kl{\"a}rwerk: Mathematische Ans{\"a}tze der Bewertung}, volume = {7}, journal = {KA Korrespondenz Abwasser, Abfall}, pages = {551 -- 557}, year = {2019}, language = {de} } @article{VenkatareddyWilkeErnstetal.2019, author = {Venkatareddy, Narendra Lagumaddepalli and Wilke, Patrick and Ernst, Natalia and Horch, Justus and Weber, Marcus and Dallmann, Andre and B{\"o}rner, Hans G.}, title = {Mussel-glue inspired adhesives: A study on the relevance of L-Dopa and the function of the sequence at nanomaterial-peptide interfaces}, volume = {6}, journal = {Advanced Materials Interfaces}, number = {13}, doi = {10.1002/admi.201900501}, pages = {1900501}, year = {2019}, abstract = {Mussel glue-proteins undergo structural transitions at material interfaces to optimize adhesive surface contacts. Those intriguing structure responses are mimicked by a mussel-glue mimetic peptide (HSY*SGWSPY*RSG (Y* = l-Dopa)) that was previously selected by phage-display to adhere to Al2O3 after enzymatic activation. Molecular level insights into the full-length adhesion domain at Al2O3 surfaces are provided by a divergent-convergent analysis, combining nuclear Overhauser enhancement based 2D NOESY and saturation transfer difference NMR analysis of submotifs along with molecular dynamics simulations of the full-length peptide. The peptide is divided into two submotifs, each containing one Dopa "anchor" (Motif-1 and 2). The analysis proves Motif-1 to constitute a dynamic Al2O3 binder and adopting an "M"-structure with multiple surface contacts. Motif-2 binds stronger by two surface contacts, forming a compact "C"-structure. Taking these datasets as constraints enables to predict the structure and propose a binding process model of the full-length peptide adhering to Al2O3.}, language = {en} } @article{DelVecchioLabuzTempetal.2019, author = {Del Vecchio, Giovanna and Labuz, Dominika and Temp, Julia and Seitz, Viola and Kloner, Michael and Negrete, Roger and Rodriguez-Gaztelumendi, Antonio and Weber, Marcus and Machelska, Halina and Stein, Christoph}, title = {pKa of opioid ligands as a discriminating factor for side effects}, volume = {9}, journal = {Scientific Reports}, doi = {10.1038/s41598-019-55886-1}, pages = {19344}, year = {2019}, abstract = {The non-selective activation of central and peripheral opioid receptors is a major shortcoming of currently available opioids. Targeting peripheral opioid receptors is a promising strategy to preclude side effects. Recently, we showed that fentanyl-derived μ-opioid receptor (MOR) agonists with reduced acid dissociation constants (pKa) due to introducing single fluorine atoms produced injury-restricted antinociception in rat models of inflammatory, postoperative and neuropathic pain. Here, we report that a new double-fluorinated compound (FF6) and fentanyl show similar pKa, MOR affinity and [35S]-GTPγS binding at low and physiological pH values. In vivo, FF6 produced antinociception in injured and non-injured tissue, and induced sedation and constipation. The comparison of several fentanyl derivatives revealed a correlation between pKa values and pH-dependent MOR activation, antinociception and side effects. An opioid ligand's pKa value may be used as discriminating factor to design safer analgesics.}, language = {en} }