Wiley Interdisciplinary Reviews: Computational Molecular Science最新文献

Quantum mechanics/molecular mechanics (QM/MM) hybrid models allow one to address chemical phenomena in complex molecular environments. Whereas this modeling approach can cope with a large system size at moderate computational costs, the models are often tedious to construct and require manual preprocessing and expertise. As a result, transferability to new application areas can be limited and the many parameters are not easy to adjust to reference data that are typically scarce. Therefore, it is desirable to devise automated procedures of controllable accuracy, which enables such modeling in a standardized and black-box-type manner. Although diverse best-practice protocols have been set up for the construction of individual components of a QM/MM model (e.g., the MM potential, the type of embedding, the choice of the QM region), automated procedures that reconcile all steps of the QM/MM model construction are still rare. Here, we review the state of the art of QM/MM modeling with a focus on automation. We elaborate on MM model parametrization, on atom-economical physically-motivated QM region selection, and on embedding schemes that incorporate mutual polarization as critical components of the QM/MM model. In view of the broad scope of the field, we mostly restrict the discussion to methodologies that build de novo models based on first-principles data, on uncertainty quantification, and on error mitigation with a high potential for automation. Ultimately, it is desirable to be able to set up reliable QM/MM models in a fast and efficient automated way without being constrained by specific chemical or technical limitations.

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The cover image is based on the Focus Article Multiscale molecular simulations to investigate adenylyl cyclase-based signaling in the brain by Siri C. van Keulen et al., https://doi.org/10.1002/wcms.1623. Image Credit: F. Colizzi

Hydrogel is a three-dimensional cross-linked hydrophilic network that can imbibe a large amount of water inside its structure (up to 99% of its dry weight). Due to their unique characteristics of biocompatibility and flexibility, it has found applications in diversified fields, including tissue engineering, drug delivery, biosensors, and agriculture. Even though hydrogels are widely used in the biomedical field, their lower mechanical strength still limits their application to its full potential. Hydrogels can be reinforced with organic, inorganic, and metal-based nanofillers to improve their mechanical strength. Due to improved computational power, computational-based techniques are emerging as a leading characterization technique for nanocomposites and hydrogels. In nanomaterials, atomistic description governs the mechanical strength and thermal behavior that realized atomistic level simulations as an appropriate approach to capture the deformation governing mechanism. Among atomistic simulations, the molecular dynamics (MD)-based approach is emerging as a prospective technique for simulating neat and nanocomposite-based hydrogels' mechanical and thermal behavior. The success and accuracy of MD simulation entirely depend on the force field. This review article will compile the force field employed by the research community to capture the atomistic interactions in different nanocomposite-based hydrogels. This article will comprehensively review the progress made in the atomistic approach to study neat and nanocomposite-based hydrogels' properties. The authors have enlightened the challenges and limitations associated with the atomistic modeling of hydrogels.

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Drug design is costly in terms of resources and time. Generative deep learning techniques are using increasing amounts of biochemical data and computing power to pave the way for a new generation of tools and methods for drug discovery and optimization. Although early methods used SMILES strings, more recent approaches use molecular graphs to naturally represent chemical entities. Graph neural networks (GNNs) are learning models that can natively process graphs. The use of GNNs in drug discovery is growing exponentially. GNNs for drug design are often coupled with conditioning techniques to steer the generation process towards desired chemical and biological properties. These conditioned graph-based generative models and frameworks hold promise for the routine application of GNNs in drug discovery.

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Catalysis has played a crucial role in energy sustainability, environment control, and chemical production, while the design of high-performance catalysts is a key scientific question. In nature, biological organisms carry out catalysis with earth-abundant metals, whereas modern industrial processes rely heavily on precious metals. This points out the necessity of designing state-of-the-art catalysts with earth-abundant elements to maintain sustainable catalysis. In this review, we will start with the fact that nature uses earth-abundant metals to feed the planet, followed by a few successful examples of catalyst design for water oxidation. Then, we will systematically introduce the practical methods in computational catalyst design and their applications in the rational modification of EAM catalysts for various reactions. In addition, the roles of high-throughput computations and artificial intelligence in this framework are summarized and discussed. We will also discuss the potential limitations of the framework and the strategies to overcome these challenges. Finally, we emphasize the importance of the synergistic efforts between theory and experiments in rational catalyst design with earth-abundant elements.

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Machine learning (ML) techniques offer a novel and exciting approach in the drug discovery field. One might even argue that their current expansion may push traditional MM modeling techniques to a secondary role in modeling methods. In this review article, we advocate that a combination of both techniques could be the most efficient implementation in the coming years. Focusing on drug-target affinity predictions, we first review pure ML approaches. Then, we introduced recent developments in mixing ML and MM methods in a single combined manner. Finally, we show the detailed implementation of a real industrial prospective study where nanomolar hits, on a kinase target, were obtained by combination of state of the art Monte Carlo MM simulations (PELE) with a ML ranking function.

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Electronic structure calculations of many-electron systems should in principle treat relativistic, correlation, and quantum electrodynamics (QED) effects simultaneously to a high precision, so as to match experimental measurements as close as possible. While both relativistic and QED effects can readily be built into the many-electron Hamiltonian, electron correlation is more difficult to describe due to the exponential growth of the number of parameters in the wave function. Compared with the spin-free case, spin–orbit interaction results in the loss of spin symmetry and concomitant complex algebra, thereby rendering the treatment of electron correlation even more difficult. Possible solutions to these issues are highlighted here.

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Brownian dynamics (BD) is a computational method to simulate molecular diffusion processes. Although the BD method has been developed over several decades and is well established, new methodological developments are improving its accuracy, widening its scope, and increasing its application. In biological applications, BD is used to investigate the diffusive behavior of molecules subject to forces due to intermolecular interactions or interactions with material surfaces. BD can be used to compute rate constants for diffusional association, generate structures of encounter complexes for molecular binding partners, and examine the transport properties of geometrically complex molecules. Often, a series of simulations is performed, for example, for different protein mutants or environmental conditions, so that the effects of the changes on diffusional properties can be estimated. While biomolecules are commonly described at atomic resolution and internal molecular motions are typically neglected, coarse-graining and the treatment of conformational flexibility are increasingly employed. Software packages for BD simulations of biomolecules are growing in capabilities, with several new packages providing novel features that expand the range of questions that can be addressed. These advances, when used in concert with experiment or other simulation methods, such as molecular dynamics, open new opportunities for application to biochemical and biological systems. Here, we review some of the latest developments in the theory, methods, software, and applications of BD simulations to study biomolecular diffusional association processes and provide a perspective on their future use and application to outstanding challenges in biology, bioengineering, and biomedicine.

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Quantum mechanical (QM) calculations are critical in quantitatively understanding the relationship between the structure and physicochemical properties of various chemical systems. However, the sharply increasing computational cost with the system size has severely hindered applying direct QM calculations on large-sized systems. Hence, linear-scaling and/or fragmentation QM methods have been proposed to overcome this difficulty. In this review, we focus on the recent development and applications of the electrostatically embedded generalized molecular fractionation with the conjugate caps (EE-GMFCC) method in probing various properties of complex large molecules and condensed-phase systems. The EE-GMFCC method is now capable of describing the localized excited states of biomolecules and molecular crystals with a chromophore. The EE-GMF method is also combined with anharmonic vibrational calculations for accurate simulation of the infrared spectrum of the magic number H⁺(H₂O)₂₁ cluster at the coupled cluster level. With an adaptive fragmentation scheme, the EE-GMF-based ab initio molecular dynamics is able to directly simulate chemical reactions occurred in atmospheric molecular clusters. Furthermore, by combining the EE-GMF(CC) method and deep machine learning techniques, neural network potentials can be efficiently constructed for accurate simulations of complex systems with the accuracy of high-level wave function methods. The EE-GMF(CC) method is expected to become a practical tool for quantitative description of complex large molecules and condensed-phase systems with high-level ab initio theories or ab initio quality potentials.

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SERENITY [J Comput Chem. 2018;39:788–798] is an open-source quantum chemistry software that provides an extensive development platform focused on quantum-mechanical multilevel and embedding approaches. In this study, we give an overview over the developments done in Serenity since its original publication in 2018. This includes efficient electronic-structure methods for ground states such as multilevel domain-based local pair natural orbital coupled cluster and Møller–Plesset perturbation theory as well as the multistate frozen-density embedding quasi-diabatization method. For the description of excited states, SERENITY features various subsystem-based methods such as embedding variants of coupled time-dependent density-functional theory, approximate second-order coupled cluster theory and the second-order algebraic diagrammatic construction technique as well as GW/Bethe–Salpeter equation approaches. SERENITY's modular structure allows combining these methods with density-functional theory (DFT)-based embedding through various practical realizations and variants of subsystem DFT including frozen-density embedding, potential-reconstruction techniques and projection-based embedding.

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