1
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Awoonor-Williams E, Golosov AA, Hornak V. Benchmarking In Silico Tools for Cysteine p Ka Prediction. J Chem Inf Model 2023; 63:2170-2180. [PMID: 36996330 DOI: 10.1021/acs.jcim.3c00004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2023]
Abstract
Accurate estimation of the pKa's of cysteine residues in proteins could inform targeted approaches in hit discovery. The pKa of a targetable cysteine residue in a disease-related protein is an important physiochemical parameter in covalent drug discovery, as it influences the fraction of nucleophilic thiolate amenable to chemical protein modification. Traditional structure-based in silico tools are limited in their predictive accuracy of cysteine pKa's relative to other titratable residues. Additionally, there are limited comprehensive benchmark assessments for cysteine pKa predictive tools. This raises the need for extensive assessment and evaluation of methods for cysteine pKa prediction. Here, we report the performance of several computational pKa methods, including single-structure and ensemble-based approaches, on a diverse test set of experimental cysteine pKa's retrieved from the PKAD database. The dataset consisted of 16 wildtype and 10 mutant proteins with experimentally measured cysteine pKa values. Our results highlight that these methods are varied in their overall predictive accuracies. Among the test set of wildtype proteins evaluated, the best method (MOE) yielded a mean absolute error of 2.3 pK units, highlighting the need for improvement of existing pKa methods for accurate cysteine pKa estimation. Given the limited accuracy of these methods, further development is needed before these approaches can be routinely employed to drive design decisions in early drug discovery efforts.
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Affiliation(s)
- Ernest Awoonor-Williams
- Novartis Institutes for BioMedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Andrei A Golosov
- Novartis Institutes for BioMedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Viktor Hornak
- Novartis Institutes for BioMedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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2
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Lazare J, Tebes-Stevens C, Weber EJ. A multiple linear regression approach to the estimation of carboxylic acid ester and lactone alkaline hydrolysis rate constants. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2023; 34:183-210. [PMID: 36951517 PMCID: PMC10547131 DOI: 10.1080/1062936x.2023.2188608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 02/25/2023] [Indexed: 05/03/2023]
Abstract
Pesticides, pharmaceuticals, and other organic contaminants often undergo hydrolysis when released into the environment; therefore, measured or estimated hydrolysis rates are needed to assess their environmental persistence. An intuitive multiple linear regression (MLR) approach was used to develop robust QSARs for predicting base-catalyzed rate constants of carboxylic acid esters (CAEs) and lactones. We explored various combinations of independent descriptors, resulting in four primary models (two for lactones and two for CAEs), with a total of 15 and 11 parameters included in the CAE and lactone QSAR models, respectively. The most significant descriptors include pKa, electronegativity, charge density, and steric parameters. Model performance is assessed using Drug Theoretics and Cheminformatics Laboratory's DTC-QSAR tool, demonstrating high accuracy for both internal validation (r2 = 0.93 and RMSE = 0.41-0.43 for CAEs; r2 = 0.90-0.93 and RMSE = 0.38-0.46 for lactones) and external validation (r2 = 0.93 and RMSE = 0.43-0.45 for CAEs; r2 = 0.94-0.98 and RMSE = 0.33-0.41 for lactones). The developed models require only low-cost computational resources and have substantially improved performance compared to existing hydrolysis rate prediction models (HYDROWIN and SPARC).
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Affiliation(s)
- Jovian Lazare
- Oak Ridge Institute for Science and Education (ORISE), hosted at U.S. Environmental Protection Agency, Athens, Georgia 30605, United States
| | - Caroline Tebes-Stevens
- Center for Environmental Measurement and Modeling, United States Environmental Protection Agency, Athens, Georgia 30605, United States
| | - Eric J. Weber
- Center for Environmental Measurement and Modeling, United States Environmental Protection Agency, Athens, Georgia 30605, United States
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3
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Banik N, Braun S, Gerit Brandenburg J, Fricker G, Kalonia DS, Rosenkranz T. Technology development to evaluate the effectiveness of viscosity reducing excipients. Int J Pharm 2022; 626:122204. [PMID: 36116691 DOI: 10.1016/j.ijpharm.2022.122204] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/05/2022] [Accepted: 09/11/2022] [Indexed: 10/14/2022]
Abstract
Addition of pharmaceutical excipients is a commonly used approach to decrease the viscosity of highly concentrated protein formulations, which otherwise could not be subcutaneously injected or processed. The variety of protein-protein interactions, which are responsible for increased viscosities, makes a portfolio approach necessary. Screening of several excipients to develop such a portfolio is time and money consuming in industrial settings. Responsible protein-protein interactions were investigated using the interaction parameter kD obtained from dynamic light scattering measurements in the studies presented herein. Together with in-silico calculated excipient parameter, kD could be used as a screening tool accelerating screening and formulation development as kD is suitable to high-throughput formats using small quantities of protein and low concentrations. A qualitative correlation between kD and high-concentration viscosity behavior could be shown in our case.
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Affiliation(s)
- Niels Banik
- Biomolecule Formulation, Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany; Institute for Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
| | - Stefan Braun
- Biomolecule Formulation, Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany
| | - Jan Gerit Brandenburg
- Chief Science and Technology Office, Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany
| | - Gert Fricker
- Institute for Pharmacy and Molecular Biotechnology, Ruprecht-Karls-University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
| | - Devendra S Kalonia
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269, United States
| | - Tobias Rosenkranz
- Biomolecule Formulation, Merck KGaA, Frankfurter Straße 250, 64293 Darmstadt, Germany.
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4
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Reis PBPS, Bertolini M, Montanari F, Rocchia W, Machuqueiro M, Clevert DA. A Fast and Interpretable Deep Learning Approach for Accurate Electrostatics-Driven p Ka Predictions in Proteins. J Chem Theory Comput 2022; 18:5068-5078. [PMID: 35837736 DOI: 10.1021/acs.jctc.2c00308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Existing computational methods for estimating pKa values in proteins rely on theoretical approximations and lengthy computations. In this work, we use a data set of 6 million theoretically determined pKa shifts to train deep learning models, which are shown to rival the physics-based predictors. These neural networks managed to infer the electrostatic contributions of different chemical groups and learned the importance of solvent exposure and close interactions, including hydrogen bonds. Although trained only using theoretical data, our pKAI+ model displayed the best accuracy in a test set of ∼750 experimental values. Inference times allow speedups of more than 1000× compared to physics-based methods. By combining speed, accuracy, and a reasonable understanding of the underlying physics, our models provide a game-changing solution for fast estimations of macroscopic pKa values from ensembles of microscopic values as well as for many downstream applications such as molecular docking and constant-pH molecular dynamics simulations.
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Affiliation(s)
| | - Marco Bertolini
- Machine Learning Research, Bayer A.G., Berlin 13353, Germany
| | | | - Walter Rocchia
- CONCEPT Lab, Istituto Italiano di Tecnologia (IIT), Via Melen 83, B Block, Genoa 16152, Italy
| | - Miguel Machuqueiro
- Biosystems and Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Campo Grande, Lisboa 1749-016, Portugal
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5
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Rombouts FJR, Hsiao CC, Bache S, De Cleyn M, Heckmann P, Leenaerts J, Martinéz-Lamenca C, Van Brandt S, Peschiulli A, Vos A, Gijsen HJM. Modulating physicochemical properties of tetrahydropyridine-2-amine BACE1 inhibitors with electron-withdrawing groups: A systematic study. Eur J Med Chem 2022; 228:114028. [PMID: 34920170 DOI: 10.1016/j.ejmech.2021.114028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/20/2021] [Accepted: 11/26/2021] [Indexed: 11/18/2022]
Abstract
A common challenge for medicinal chemists is to reduce the pKa of strongly basic groups' conjugate acids into a range that preserves the desired effects, usually potency and/or solubility, but avoids undesired effects like high volume of distribution (Vd), limited membrane permeation, and off-target binding to, notably, the hERG channel and monoamine receptors. We faced this challenge with a 3,4,5,6-tetrahydropyridine-2-amine scaffold harboring an amidine, a key structural component of potential inhibitors of BACE1, the rate-limiting enzyme in the production of Aβ species that make up amyloid plaques in Alzheimer's disease. In our endeavor to balance potency with desirable properties to achieve brain penetration, we introduced a diverse set of groups in beta position of the amidine that modulate logD, PSA and pKa. Given the synthetic challenge to prepare these highly functionalized warheads, we first developed a design flow including predicted physicochemical parameters which allowed us to select only the most promising candidates for synthesis. For this we evaluated a set of commercial packages to predict physicochemical properties, which can guide medicinal chemists in their endeavors to modulate pKa values of amidine and amine bases.
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Affiliation(s)
| | - Chien-Chi Hsiao
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Solène Bache
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Michel De Cleyn
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Pauline Heckmann
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Jos Leenaerts
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | | | - Sven Van Brandt
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Aldo Peschiulli
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Ann Vos
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
| | - Harrie J M Gijsen
- Janssen Research & Development, Turnhoutseweg 30, B-2340, Beerse, Belgium
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6
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Morency M, Néron S, Iftimie R, Wuest JD. Predicting p Ka Values of Quinols and Related Aromatic Compounds with Multiple OH Groups. J Org Chem 2021; 86:14444-14460. [PMID: 34613729 DOI: 10.1021/acs.joc.1c01279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Quinonoid compounds play central roles as redox-active agents in photosynthesis and respiration and are also promising replacements for inorganic materials currently used in batteries. To design new quinonoid compounds and predict their state of protonation and redox behavior under various conditions, their pKa values must be known. Methods that can predict the pKa values of simple phenols cannot reliably handle complex analogues in which multiple OH groups are present and may form intramolecular hydrogen bonds. We have therefore developed a straightforward method based on a linear relationship between experimental pKa values and calculated differences in energy between quinols and their deprotonated forms. Simple adjustments allow reliable predictions of pKa values when intramolecular hydrogen bonds are present. Our approach has been validated by showing that predicted and experimental values for over 100 quinols and related compounds differ by an average of only 0.3 units. This accuracy makes it possible to select proper pKa values when experimental data vary, predict the acidity of quinols and related compounds before they are made, and determine the sites and orders of deprotonation in complex structures with multiple OH groups.
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Affiliation(s)
- Mathieu Morency
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3, Canada
| | - Sébastien Néron
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3, Canada
| | - Radu Iftimie
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3, Canada
| | - James D Wuest
- Département de Chimie, Université de Montréal, Montréal, Québec H2V 0B3, Canada
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7
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Lawler R, Liu YH, Majaya N, Allam O, Ju H, Kim JY, Jang SS. DFT-Machine Learning Approach for Accurate Prediction of p Ka. J Phys Chem A 2021; 125:8712-8722. [PMID: 34554744 DOI: 10.1021/acs.jpca.1c05031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we propose a novel method of pKa prediction in a diverse set of acids, which combines density functional theory (DFT) method with machine learning (ML) methods. First, the DFT method with B3LYP/6-31++G**/SM8 is used to predict pKa, yielding a mean absolute error of 1.85 pKa units. Subsequently, such pKa values predicted from the DFT method are employed as one of 10 molecular descriptors for developing ML models trained on experimental data. Kernel Ridge Regression (KRR), Gaussian Process Regression, and Artificial Neural Network are optimized using three Pipelines: Pipeline 1 involving only hyperparameter optimization (HPO), Pipeline 2 involving HPO followed by a relative contribution analysis (RCA) and recursive feature elimination (RFE), and Pipeline 3 involving HPO followed by RCA and RFE on an expanded set of composite features. Finally, it is demonstrated that KRR with Pipeline 3 yields optimal pKa prediction at an MAE of 0.60 log units. This algorithm was then utilized to predict the pKa of 37 novel acids. The two most important features were determined to be the number of hydrogen atoms in the molecule and the degree of oxidation of the acid. The predicted pKa values were documented for future reference.
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Affiliation(s)
- Robin Lawler
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.,School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Yao-Hao Liu
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Nessa Majaya
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
| | - Omar Allam
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.,G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Hyunchul Ju
- Department of Mechanical Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea
| | - Jin Young Kim
- Center for Hydrogen Fuel Cell Research, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea
| | - Seung Soon Jang
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States
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8
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Chen J, Hu J, Xu Y, Krasny R, Geng W. Computing Protein pKas Using the TABI Poisson–Boltzmann Solver. JOURNAL OF COMPUTATIONAL BIOPHYSICS AND CHEMISTRY 2021. [DOI: 10.1142/s2737416520420065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A common approach to computing protein pKas uses a continuum dielectric model in which the protein is a low dielectric medium with embedded atomic point charges, the solvent is a high dielectric medium with a Boltzmann distribution of ionic charges, and the pKa is related to the electrostatic free energy which is obtained by solving the Poisson–Boltzmann equation. Starting from the model pKa for a titrating residue, the method obtains the intrinsic pKa and then computes the protonation probability for a given pH including site–site interactions. This approach assumes that acid dissociation does not affect protein conformation aside from adding or deleting charges at titratable sites. In this work, we demonstrate our treecode-accelerated boundary integral (TABI) solver for the relevant electrostatic calculations. The pKa computing procedure is enclosed in a convenient Python wrapper which is publicly available at the corresponding author’s website. Predicted results are compared with experimental pKas for several proteins. Among ongoing efforts to improve protein pKa calculations, the advantage of TABI is that it reduces the numerical errors in the electrostatic calculations so that attention can be focused on modeling assumptions.
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Affiliation(s)
- Jiahui Chen
- Department of Mathematics, Michigan State University, East Lansing, MI 48824, USA
| | - Jingzhen Hu
- Department of Mathematics, Duke University, Durham, NC 27710, USA
| | - Yongjia Xu
- Department of Mathematics, Southern Methodist University, Dallas, TX 75275, USA
| | - Robert Krasny
- Department of Mathematics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Weihua Geng
- Department of Mathematics, Southern Methodist University, Dallas, TX 75275, USA
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9
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Dutra FR, Silva CDS, Custodio R. On the Accuracy of the Direct Method to Calculate p Ka from Electronic Structure Calculations. J Phys Chem A 2020; 125:65-73. [PMID: 33356255 PMCID: PMC7872415 DOI: 10.1021/acs.jpca.0c08283] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
![]()
The
direct method (HA(soln) ⇌ A(soln)– + H(soln)+) for calculating
pKa of monoprotic acids is as efficient
as thermodynamic cycles. A selective adjustment of proton free energy
in solution was used with experimental pKa data. The procedure was analyzed at different levels of theory.
The solvent was described by the solvation model density (SMD) model,
including or not explicit water molecules, and three training sets
were tested. The best performance under any condition was obtained
by the G4CEP method with a mean absolute error close to 0.5 units
of pKa and an uncertainty around ±1
unit of pKa for any training set including
or excluding explicit solvent molecules. PM6 and AM1 performed very
well with average absolute errors below 0.75 units of pKa but with uncertainties up to ±2 units of pKa, using only the SMD solvent model. Density
functional theory (DFT) results were highly dependent on the basis
functions and explicit water molecules. The best performance was observed
for the local spin density approximation (LSDA) functional in almost
all calculations and under certain conditions, as high as those obtained
by G4CEP. Basis set complexity and explicit solvent molecules were
important factors to control DFT calculations. The training set molecules
should consider the diversity of compounds.
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Affiliation(s)
- Felipe Ribeiro Dutra
- Instituto de Química, Universidade Estadual de Campinas, P.O. Box 6154, Barão Geraldo, 13083-970 Campinas, São Paulo, Brazil
| | - Cleuton de Souza Silva
- Instituto de Ciências Exatas e Tecnologia, Universidade Federal do Amazonas, Campus de Itacoatiara, 69100-021 Itacoatiara, Amazonas, Brazil
| | - Rogério Custodio
- Instituto de Química, Universidade Estadual de Campinas, P.O. Box 6154, Barão Geraldo, 13083-970 Campinas, São Paulo, Brazil
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10
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Lara-Popoca J, Thoke HS, Stock RP, Rudino-Pinera E, Bagatolli LA. Inductive effects in amino acids and peptides: Ionization constants and tryptophan fluorescence. Biochem Biophys Rep 2020; 24:100802. [PMID: 32984556 PMCID: PMC7498751 DOI: 10.1016/j.bbrep.2020.100802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 07/26/2020] [Accepted: 07/27/2020] [Indexed: 10/26/2022] Open
Abstract
Although inductive effects in organic compounds are known to influence chemical properties such as ionization constants, their specific contribution to the properties/behavior of amino acids and functional groups in peptides remains largely unexplored. In this study we developed a computationally economical algorithm for ab initio calculation of the magnitude of inductive effects for non-aromatic molecules. The value obtained by the algorithm is called the Inductive Index and we observed a high correlation (R2 = 0.9427) between our calculations and the pKa values of the alpha-amino groups of amino acids with non-aromatic side-chains. Using a series of modified amino acids, we also found similarly high correlations (R2 > 0.9600) between Inductive Indexes and two wholly independent chemical properties: i) the pKa values of ionizable side-chains and, ii) the fluorescence response of the indole group of tryptophan. After assessing the applicability of the method of calculation at the amino acid level, we extended our study to tryptophan-containing peptides and established that inductive contributions of neighboring side-chains are transmitted through peptide bonds. We discuss possible contributions to the study of proteins.
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Affiliation(s)
- Jesús Lara-Popoca
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad #2001, Col. Chamilpa, 62210, Cuernavaca, Morelos, Mexico
| | - Henrik S Thoke
- MEMPHYS - International and Interdisciplinary Research Network, Odense, Denmark
| | - Roberto P Stock
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad #2001, Col. Chamilpa, 62210, Cuernavaca, Morelos, Mexico
| | - Enrique Rudino-Pinera
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Departamento de Medicina Molecular y Bioprocesos, Av. Universidad #2001, Col. Chamilpa, 62210, Cuernavaca, Morelos, Mexico
| | - Luis A Bagatolli
- MEMPHYS - International and Interdisciplinary Research Network, Odense, Denmark.,Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC-CONICET-Universidad Nacional de Córdoba), Friuli 2434, 5016, Córdoba, Argentina
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11
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Yang Q, Li Y, Yang J, Liu Y, Zhang L, Luo S, Cheng J. Holistic Prediction of the p
K
a
in Diverse Solvents Based on a Machine‐Learning Approach. Angew Chem Int Ed Engl 2020; 59:19282-19291. [DOI: 10.1002/anie.202008528] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/13/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Qi Yang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Yao Li
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Jin‐Dong Yang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Yidi Liu
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Long Zhang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Sanzhong Luo
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Jin‐Pei Cheng
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
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12
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Yang Q, Li Y, Yang J, Liu Y, Zhang L, Luo S, Cheng J. Holistic Prediction of the p
K
a
in Diverse Solvents Based on a Machine‐Learning Approach. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008528] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Qi Yang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Yao Li
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Jin‐Dong Yang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Yidi Liu
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Long Zhang
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Sanzhong Luo
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
| | - Jin‐Pei Cheng
- Center of Basic Molecular Science Department of Chemistry Tsinghua University 100084 Beijing China
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13
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Standard state free energies, not pK as, are ideal for describing small molecule protonation and tautomeric states. J Comput Aided Mol Des 2020; 34:561-573. [PMID: 32052350 DOI: 10.1007/s10822-020-00280-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/08/2020] [Indexed: 12/14/2022]
Abstract
The pKa is the standard measure used to describe the aqueous proton affinity of a compound, indicating the proton concentration (pH) at which two protonation states (e.g. A- and AH) have equal free energy. However, compounds can have additional protonation states (e.g. AH2+), and may assume multiple tautomeric forms, with the protons in different positions (microstates). Macroscopic pKas give the pH where the molecule changes its total number of protons, while microscopic pKas identify the tautomeric states involved. As tautomers have the same number of protons, the free energy difference between them and their relative probability is pH independent so there is no pKa connecting them. The question arises: What is the best way to describe protonation equilibria of a complex molecule in any pH range? Knowing the number of protons and the relative free energy of all microstates at a single pH, ∆G°, provides all the information needed to determine the free energy, and thus the probability of each microstate at each pH. Microstate probabilities as a function of pH generate titration curves that highlight the low energy, observable microstates, which can then be compared with experiment. A network description connecting microstates as nodes makes it straightforward to test thermodynamic consistency of microstate free energies. The utility of this analysis is illustrated by a description of one molecule from the SAMPL6 Blind pKa Prediction Challenge. Analysis of microstate ∆G°s also makes a more compact way to archive and compare the pH dependent behavior of compounds with multiple protonatable sites.
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14
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Lu Y, Anand S, Shirley W, Gedeck P, Kelley BP, Skolnik S, Rodde S, Nguyen M, Lindvall M, Jia W. Prediction of pKa Using Machine Learning Methods with Rooted Topological Torsion Fingerprints: Application to Aliphatic Amines. J Chem Inf Model 2019; 59:4706-4719. [DOI: 10.1021/acs.jcim.9b00498] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Yipin Lu
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Shankara Anand
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - William Shirley
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Peter Gedeck
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Brian P. Kelley
- Novartis Institutes for Biomedical Research, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Suzanne Skolnik
- Novartis Institutes for Biomedical Research, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Stephane Rodde
- Novartis Institutes for Biomedical Research, Postfach, CH-4002 Basel, Switzerland
| | - Mai Nguyen
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Mika Lindvall
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Weiping Jia
- Novartis Institutes for Biomedical Research, 5300 Chiron Way, Emeryville, California 94608, United States
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15
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Duša F, Moravcová D, Šlais K. Low-molecular-mass nitrophenol-based compounds suitable for the effective tracking of pH gradient in isoelectric focusing. Anal Chim Acta 2019; 1076:144-153. [DOI: 10.1016/j.aca.2019.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/03/2019] [Accepted: 05/05/2019] [Indexed: 11/29/2022]
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16
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Mansouri K, Cariello NF, Korotcov A, Tkachenko V, Grulke CM, Sprankle CS, Allen D, Casey WM, Kleinstreuer NC, Williams AJ. Open-source QSAR models for pKa prediction using multiple machine learning approaches. J Cheminform 2019; 11:60. [PMID: 33430972 PMCID: PMC6749653 DOI: 10.1186/s13321-019-0384-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/03/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The logarithmic acid dissociation constant pKa reflects the ionization of a chemical, which affects lipophilicity, solubility, protein binding, and ability to pass through the plasma membrane. Thus, pKa affects chemical absorption, distribution, metabolism, excretion, and toxicity properties. Multiple proprietary software packages exist for the prediction of pKa, but to the best of our knowledge no free and open-source programs exist for this purpose. Using a freely available data set and three machine learning approaches, we developed open-source models for pKa prediction. METHODS The experimental strongest acidic and strongest basic pKa values in water for 7912 chemicals were obtained from DataWarrior, a freely available software package. Chemical structures were curated and standardized for quantitative structure-activity relationship (QSAR) modeling using KNIME, and a subset comprising 79% of the initial set was used for modeling. To evaluate different approaches to modeling, several datasets were constructed based on different processing of chemical structures with acidic and/or basic pKas. Continuous molecular descriptors, binary fingerprints, and fragment counts were generated using PaDEL, and pKa prediction models were created using three machine learning methods, (1) support vector machines (SVM) combined with k-nearest neighbors (kNN), (2) extreme gradient boosting (XGB) and (3) deep neural networks (DNN). RESULTS The three methods delivered comparable performances on the training and test sets with a root-mean-squared error (RMSE) around 1.5 and a coefficient of determination (R2) around 0.80. Two commercial pKa predictors from ACD/Labs and ChemAxon were used to benchmark the three best models developed in this work, and performance of our models compared favorably to the commercial products. CONCLUSIONS This work provides multiple QSAR models to predict the strongest acidic and strongest basic pKas of chemicals, built using publicly available data, and provided as free and open-source software on GitHub.
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Affiliation(s)
- Kamel Mansouri
- Integrated Laboratory Systems, Inc., P.O. Box 13501, Research Triangle Park, NC 27709 USA
| | - Neal F. Cariello
- Integrated Laboratory Systems, Inc., P.O. Box 13501, Research Triangle Park, NC 27709 USA
| | - Alexandru Korotcov
- Science Data Software LLC, 14914 Bradwill Court, Rockville, MD 20850 USA
| | - Valery Tkachenko
- Science Data Software LLC, 14914 Bradwill Court, Rockville, MD 20850 USA
| | - Chris M. Grulke
- National Center for Computational Toxicology, U.S. Environmental Protection Agency, 109 T.W. Alexander Dr., Mail Code D143-02, Research Triangle Park, NC 27709 USA
| | - Catherine S. Sprankle
- Integrated Laboratory Systems, Inc., P.O. Box 13501, Research Triangle Park, NC 27709 USA
| | - David Allen
- Integrated Laboratory Systems, Inc., P.O. Box 13501, Research Triangle Park, NC 27709 USA
| | - Warren M. Casey
- National Institute of Environmental Health Sciences, P.O. Box 12233, Mail Stop K2-16, Research Triangle Park, NC 27709 USA
| | - Nicole C. Kleinstreuer
- National Institute of Environmental Health Sciences, P.O. Box 12233, Mail Stop K2-16, Research Triangle Park, NC 27709 USA
| | - Antony J. Williams
- National Center for Computational Toxicology, U.S. Environmental Protection Agency, 109 T.W. Alexander Dr., Mail Code D143-02, Research Triangle Park, NC 27709 USA
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17
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A Way towards Reliable Predictive Methods for the Prediction of Physicochemical Properties of Chemicals Using the Group Contribution and other Methods. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9081700] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Physicochemical properties of chemicals as referred to in this review include, for example, thermodynamic properties such as heat of formation, boiling point, toxicity of molecules and the fate of molecules whenever undergoing or accelerating (catalytic) a chemical reaction and therewith about chemical equilibrium, that is, the equilibrium in chemical reactions. All such properties have been predicted in literature by a variety of methods. However, for the experimental scientist for whom such predictions are of relevance, the accuracies are often far from sufficient for reliable application We discuss current practices and suggest how one could arrive at better, that is sufficiently accurate and reliable, predictive methods. Some recently published examples have shown this to be possible in practical cases. In summary, this review focuses on methodologies to obtain the required accuracies for the chemical practitioner and process technologist designing chemical processes. Finally, something almost never explicitly mentioned is the fact that whereas for some practical cases very accurate predictions are required, for other cases a qualitatively correct picture with relatively low correlation coefficients can be sufficient as a valuable predictive tool. Requirements for acceptable predictive methods can therefore be significantly different depending on the actual application, which are illustrated using real-life examples, primarily with industrial relevance. Furthermore, for specific properties such as the octanol-water partition coefficient more close collaboration between research groups using different methods would greatly facilitate progress in the field of predictive modelling.
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18
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Raevsky OA, Grigorev VY, Polianczyk DE, Raevskaja OE, Dearden JC. Aqueous Drug Solubility: What Do We Measure, Calculate and QSPR Predict? Mini Rev Med Chem 2019; 19:362-372. [PMID: 30058484 DOI: 10.2174/1389557518666180727164417] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 07/06/2018] [Accepted: 07/20/2018] [Indexed: 01/07/2023]
Abstract
Detailed critical analysis of publications devoted to QSPR of aqueous solubility is presented in the review with discussion of four types of aqueous solubility (three different thermodynamic solubilities with unknown solute structure, intrinsic solubility, solubility in physiological media at pH=7.4 and kinetic solubility), variety of molecular descriptors (from topological to quantum chemical), traditional statistical and machine learning methods as well as original QSPR models.
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Affiliation(s)
- Oleg A Raevsky
- Department of Computer-Aided Molecular Design, Institute of Physiologically Active Compounds, Russian Academy of Science, Chernogolovka, Russian Federation
| | - Veniamin Y Grigorev
- Department of Computer-Aided Molecular Design, Institute of Physiologically Active Compounds, Russian Academy of Science, Chernogolovka, Russian Federation
| | - Daniel E Polianczyk
- Department of Computer-Aided Molecular Design, Institute of Physiologically Active Compounds, Russian Academy of Science, Chernogolovka, Russian Federation
| | - Olga E Raevskaja
- Department of Computer-Aided Molecular Design, Institute of Physiologically Active Compounds, Russian Academy of Science, Chernogolovka, Russian Federation
| | - John C Dearden
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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19
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Ramos-Guzmán CA, Zinovjev K, Tuñón I. Modeling caspase-1 inhibition: Implications for catalytic mechanism and drug design. Eur J Med Chem 2019; 169:159-167. [PMID: 30875506 DOI: 10.1016/j.ejmech.2019.02.064] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/21/2019] [Accepted: 02/23/2019] [Indexed: 10/27/2022]
Abstract
The metabolic product of caspase-1, IL-1β, is an important mediator in inflammation and pyroptosis cell death process. Alzheimer's disease, septic shock and rheumatoid arthritis are IL-1β mediated diseases, making the caspase-1 an interesting target of pharmacological value. Many inhibitors have been developed until now, most of them are peptidomimetic with improved potency. In the present study, all-atom molecular dynamics simulations and the MM/GBSA method were employed to reproduce and interpret the results obtained by in vitro experiments for a series of inhibitors. The analysis shows that the tautomeric state of the catalytic His237 impact significantly the performance of the prediction protocol, providing evidence for a His237 tautomeric state different to the proposed in the putative mechanism. Additionally, analysis of inhibitor-enzyme interactions indicates that the differences in the inhibitory potency of the tested ligands can be explained mainly by the interaction of the inhibitors with the S2-S4 protein region. These results provide guidelines for subsequent studies of caspase-1 catalytic reaction mechanism and for the design of novel inhibitors.
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Affiliation(s)
- Carlos A Ramos-Guzmán
- Departamento de Química Física, Universidad de Valencia, Burjassot, Valencia, 46100, Spain
| | - Kirill Zinovjev
- Departamento de Química Física, Universidad de Valencia, Burjassot, Valencia, 46100, Spain
| | - Iñaki Tuñón
- Departamento de Química Física, Universidad de Valencia, Burjassot, Valencia, 46100, Spain.
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20
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Nolte TM, Peijnenburg WJGM. Use of quantum-chemical descriptors to analyse reaction rate constants between organic chemicals and superoxide/hydroperoxyl (O2•−/HO2•). Free Radic Res 2018; 52:1118-1131. [DOI: 10.1080/10715762.2018.1529867] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Tom M. Nolte
- Department of Environmental Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Nijmegen, the Netherlands
- Laboratory of Inorganic Chemistry, Eidgenossische Technische Hochschule (ETH) Zurich, Zurich, Switzerland
| | - Willie J. G. M. Peijnenburg
- National Institute of Public Health and the Environment, Bilthoven, The Netherlands
- Institute of Environmental Sciences (CML), Leiden University, Leiden, The Netherlands
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21
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Prasad S, Huang J, Zeng Q, Brooks BR. An explicit-solvent hybrid QM and MM approach for predicting pKa of small molecules in SAMPL6 challenge. J Comput Aided Mol Des 2018; 32:1191-1201. [PMID: 30276503 PMCID: PMC6342563 DOI: 10.1007/s10822-018-0167-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/25/2018] [Indexed: 12/30/2022]
Abstract
In this work we have developed a hybrid QM and MM approach to predict pKa of small drug-like molecules in explicit solvent. The gas phase free energy of deprotonation is calculated using the M06-2X density functional theory level with Pople basis sets. The solvation free energy difference of the acid and its conjugate base is calculated at MD level using thermodynamic integration. We applied this method to the 24 drug-like molecules in the SAMPL6 blind pKa prediction challenge. We achieved an overall RMSE of 2.4 pKa units in our prediction. Our results show that further optimization of the protocol needs to be done before this method can be used as an alternative approach to the well established approaches of a full quantum level or empirical pKa prediction methods.
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Affiliation(s)
- Samarjeet Prasad
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20814, USA.
- Biophysics and Biophysical Chemistry, The Johns Hopkins University, School of Medicine, Baltimore, MD, 21205, USA.
| | - Jing Huang
- School of Life Sciences, Westlake University, 18 Shilongshan Street, Xihu District, Hangzhou, Zhejiang, China
| | - Qiao Zeng
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20814, USA
| | - Bernard R Brooks
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, 20814, USA
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22
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Xiong J, Zhang C, Xu D. Catalytic mechanism of type C sialidase from Streptococcus pneumoniae: from covalent intermediate to final product. J Mol Model 2018; 24:297. [PMID: 30259133 DOI: 10.1007/s00894-018-3822-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 09/04/2018] [Indexed: 12/24/2022]
Abstract
Streptococcus pneumoniae is a Gram-positive human pathogenic bacterium, which is the main cause of pneumonia and meningitis in children and the elderly. Three sialidases (or neuraminidases) encoded from Streptococcus pneumoniae could catalyze the cleavage of sialic acid linkages. This mechanism is directly connected with infection, apoptosis, and signaling, and usually considered to be one of the critical virulence factors. Type C neuraminidase (NanC) is unique because its primary product of Neu5Ac2en is considered to be an inhibitor to the other two sialidases. Experimentally, there are two different pathways for the formation mechanism of Neu5Ac2en catalyzed by NanC. In this work, a combined quantum mechanical and molecular mechanical approach was employed in all calculations. Starting from the covalent sialylated intermediate, we first examined the reaction to Neu5Ac2en and found the reaction prefers a direct proton abstraction mechanism rather than the water mediated proton abstraction mechanism. Free energy profiles can confirm that Neu5Ac2en is the major product of NanC. Functional roles of some important residues were also investigated, e.g., D315 acts as the proton acceptor during the formation of Neu5Ac2en, while the general base for the hydrolytic reaction to Neu5Ac. This study can facilitate the understanding of the catalytic mechanism of NanC and has the potential to aid in future inhibitor design studies.
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Affiliation(s)
- Jing Xiong
- MOE Key Laboratory of Green Chemistry & Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan, 610064, People's Republic of China
- School of Pharmacy, Chengdu Medical College, Chengdu, Sichuan, 610500, People's Republic of China
| | - Chunchun Zhang
- Analytical&Testing Center, Sichuan University, Chengdu, Sichuan, 610064, People's Republic of China.
| | - Dingguo Xu
- MOE Key Laboratory of Green Chemistry & Technology, College of Chemistry, Sichuan University, Chengdu, Sichuan, 610064, People's Republic of China.
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23
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Zeng Q, Jones MR, Brooks BR. Absolute and relative pK a predictions via a DFT approach applied to the SAMPL6 blind challenge. J Comput Aided Mol Des 2018; 32:1179-1189. [PMID: 30128926 DOI: 10.1007/s10822-018-0150-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/09/2018] [Indexed: 12/25/2022]
Abstract
In this work, quantum mechanical methods were used to predict the microscopic and macroscopic pKa values for a set of 24 molecules as a part of the SAMPL6 blind challenge. The SMD solvation model was employed with M06-2X and different basis sets to evaluate three pKa calculation schemes (direct, vertical, and adiabatic). The adiabatic scheme is the most accurate approach (RMSE = 1.40 pKa units) and has high correlation (R2 = 0.93), with respect to experiment. This approach can be improved by applying a linear correction to yield an RMSE of 0.73 pKa units. Additionally, we consider including explicit solvent representation and multiple lower-energy conformations to improve the predictions for outliers. Adding three water molecules explicitly can reduce the error by 2-4 pKa units, with respect to experiment, whereas including multiple local minima conformations does not necessarily improve the pKa prediction.
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Affiliation(s)
- Qiao Zeng
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, 12 South Drive, Building 12A Room 3053, Bethesda, MD, 20814, USA.
| | - Michael R Jones
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, 12 South Drive, Building 12A Room 3053, Bethesda, MD, 20814, USA
| | - Bernard R Brooks
- Laboratory of Computational Biology, National Heart, Lung and Blood Institute, National Institutes of Health, 12 South Drive, Building 12A Room 3053, Bethesda, MD, 20814, USA
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24
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Selwa E, Kenney IM, Beckstein O, Iorga BI. SAMPL6: calculation of macroscopic pK a values from ab initio quantum mechanical free energies. J Comput Aided Mol Des 2018; 32:1203-1216. [PMID: 30084080 DOI: 10.1007/s10822-018-0138-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 07/21/2018] [Indexed: 12/16/2022]
Abstract
Macroscopic pKa values were calculated for all compounds in the SAMPL6 blind prediction challenge, based on quantum chemical calculations with a continuum solvation model and a linear correction derived from a small training set. Microscopic pKa values were derived from the gas-phase free energy difference between protonated and deprotonated forms together with the Conductor-like Polarizable Continuum Solvation Model and the experimental solvation free energy of the proton. pH-dependent microstate free energies were obtained from the microscopic pKas with a maximum likelihood estimator and appropriately summed to yield macroscopic pKa values or microstate populations as function of pH. We assessed the accuracy of three approaches to calculate the microscopic pKas: direct use of the quantum mechanical free energy differences and correction of the direct values for short-comings in the QM solvation model with two different linear models that we independently derived from a small training set of 38 compounds with known pKa. The predictions that were corrected with the linear models had much better accuracy [root-mean-square error (RMSE) 2.04 and 1.95 pKa units] than the direct calculation (RMSE 3.74). Statistical measures indicate that some systematic errors remain, likely due to differences in the SAMPL6 data set and the small training set with respect to their interactions with water. Overall, the current approach provides a viable physics-based route to estimate macroscopic pKa values for novel compounds with reasonable accuracy.
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Affiliation(s)
- Edithe Selwa
- Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Saclay, Labex LERMIT, 1 Avenue de la Terrasse, 91198, Gif-sur-Yvette, France
| | - Ian M Kenney
- Department of Physics, Arizona State University, P.O. Box 871504, Tempe, AZ, 85287-1504, USA
| | - Oliver Beckstein
- Department of Physics, Arizona State University, P.O. Box 871504, Tempe, AZ, 85287-1504, USA. .,Center for Biological Physics, Arizona State University, P.O. Box 871504, Tempe, AZ, 85287-1504, USA.
| | - Bogdan I Iorga
- Institut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Saclay, Labex LERMIT, 1 Avenue de la Terrasse, 91198, Gif-sur-Yvette, France.
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25
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Dardonville C. Automated techniques in pK a determination: Low, medium and high-throughput screening methods. DRUG DISCOVERY TODAY. TECHNOLOGIES 2018; 27:49-58. [PMID: 30103863 DOI: 10.1016/j.ddtec.2018.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/03/2018] [Accepted: 04/05/2018] [Indexed: 06/08/2023]
Abstract
Drug discovery programs that generate hundreds of new molecular entities need efficient methodologies for physicochemical profiling. Several high-throughput methods for pKa screening have been developed in the last 15 years to determine this key physicochemical parameter. Separation techniques such as HPLC-MS or capillary electrophoresis are particularly well-suited due to their high throughput and capacity to deal with impure or complex samples. In addition, potentiometric and (mostly) UV-metric-based methods (plate-based and automated systems), find their place as very precise methodologies for pKa determination despite of somewhat lower throughput. Finally, pKa prediction software packages are useful estimator tools but, to date, they cannot replace experimental measurements when accurate pKa values are required.
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26
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Yang JD, Ji P, Xue XS, Cheng JP. Recent Advances and Advisable Applications of Bond Energetics in Organic Chemistry. J Am Chem Soc 2018; 140:8611-8623. [DOI: 10.1021/jacs.8b04104] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jin-Dong Yang
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Pengju Ji
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Xiao-Song Xue
- State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Centre of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China
- State Key Laboratory of Elemento-organic Chemistry, Collaborative Innovation Centre of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
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27
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Spahn V, Del Vecchio G, Rodriguez-Gaztelumendi A, Temp J, Labuz D, Kloner M, Reidelbach M, Machelska H, Weber M, Stein C. Opioid receptor signaling, analgesic and side effects induced by a computationally designed pH-dependent agonist. Sci Rep 2018; 8:8965. [PMID: 29895890 PMCID: PMC5997768 DOI: 10.1038/s41598-018-27313-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 05/31/2018] [Indexed: 12/26/2022] Open
Abstract
Novel pain killers without adverse effects are urgently needed. Opioids induce central and intestinal side effects such as respiratory depression, sedation, addiction, and constipation. We have recently shown that a newly designed agonist with a reduced acid dissociation constant (pKa) abolished pain by selectively activating peripheral μ-opioid receptors (MOR) in inflamed (acidic) tissues without eliciting side effects. Here, we extended this concept in that pKa reduction to 7.22 was achieved by placing a fluorine atom at the ethylidene bridge in the parental molecule fentanyl. The new compound (FF3) showed pH-sensitive MOR affinity, [35S]-GTPγS binding, and G protein dissociation by fluorescence resonance energy transfer. It produced injury-restricted analgesia in rat models of inflammatory, postoperative, abdominal, and neuropathic pain. At high dosages, FF3 induced sedation, motor disturbance, reward, constipation, and respiratory depression. These results support our hypothesis that a ligand’s pKa should be close to the pH of injured tissue to obtain analgesia without side effects.
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Affiliation(s)
- Viola Spahn
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Giovanna Del Vecchio
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Antonio Rodriguez-Gaztelumendi
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.,Department of Drug Discovery and In Vitro Pharmacology, Laboratorios Dr. Esteve, Parc Científic de Barcelona, Barcelona, Spain
| | - Julia Temp
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Dominika Labuz
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Michael Kloner
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Marco Reidelbach
- Freie Universität Berlin, Institute of Theoretical Physics, Arnimallee 14, 14195, Berlin, Germany
| | - Halina Machelska
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Marcus Weber
- Zuse Institute Berlin, Computational Molecular Design, Takustraße 7, 14195, Berlin, Germany
| | - Christoph Stein
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Anesthesiology and Intensive Care Medicine, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
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28
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Ayine-Tora DM, Reynisson J. The Utility of Calculated Proton Affinities in Drug Design: A DFT Study. Aust J Chem 2018. [DOI: 10.1071/ch18225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Computer-aided drug design comprises several predictive tools, which can calculate various properties of the candidates under development. Proton affinity (PA) is related to pKa (the negative log of the acid dissociation constant (Ka)) one of the fundamental physical properties of drug candidates, determining their water solubility and thus their pharmacokinetic profile. The following questions therefore emerged: to what extent are PA predictions useful in drug design, and can they be reliably used to derive pKa values? Using density functional theory (DFT), it was established that for violuric acid, with three ionisation groups, the PAs correlate well with the measured pKas (R2 = 0.990). Furthermore, an excellent correlation within the amiloride compound family was achieved (R2 = 0.922). In order to obtain correlations for larger compound collections (n = 210), division into chemical families was necessary: carboxylic acids (R2 = 0.665), phenols (R2 = 0.871), and nitrogen-containing molecules (R2 = 0.742). These linear relationships were used to predict pKa values of 90 drug molecules with known pKas. A total of 48 % of the calculated values were within 1 logarithmic unit of the experimental number, but mainstream empirically based methods easily outperform this approach. The conclusion can therefore be reached that PA values cannot be reliably used for predicting pKa values globally but are useful within chemical families and in the event where a specific tautomer of a drug needs to be identified.
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30
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Zühlke M, Sass S, Riebe D, Beitz T, Löhmannsröben HG. Real-Time Reaction Monitoring of an Organic Multistep Reaction by Electrospray Ionization-Ion Mobility Spectrometry. Chempluschem 2017; 82:1266-1273. [DOI: 10.1002/cplu.201700296] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 08/18/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Martin Zühlke
- University of Potsdam; Physical Chemistry; Karl-Liebknecht-Strasse 24-25 14476 Potsdam-Golm Germany
| | - Stephan Sass
- University of Potsdam; Physical Chemistry; Karl-Liebknecht-Strasse 24-25 14476 Potsdam-Golm Germany
| | - Daniel Riebe
- University of Potsdam; Physical Chemistry; Karl-Liebknecht-Strasse 24-25 14476 Potsdam-Golm Germany
| | - Toralf Beitz
- University of Potsdam; Physical Chemistry; Karl-Liebknecht-Strasse 24-25 14476 Potsdam-Golm Germany
| | - Hans-Gerd Löhmannsröben
- University of Potsdam; Physical Chemistry; Karl-Liebknecht-Strasse 24-25 14476 Potsdam-Golm Germany
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31
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Proton dissociation properties of arylphosphonates: Determination of accurate Hammett equation parameters. J Pharm Biomed Anal 2017; 143:101-109. [PMID: 28578253 DOI: 10.1016/j.jpba.2017.05.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 05/19/2017] [Accepted: 05/21/2017] [Indexed: 11/23/2022]
Abstract
Determination of the proton dissociation constants of several arylphosphonic acid derivatives was carried out to investigate the accuracy of the Hammett equations available for this family of compounds. For the measurement of the pKa values modern, accurate methods, such as the differential potentiometric titration and NMR-pH titration were used. We found our results significantly different from the pKa values reported before (pKa1: MAE = 0.16 pKa2: MAE=0.59). Based on our recently measured pKa values, refined Hammett equations were determined that might be used for predicting highly accurate ionization constants of newly synthesized compounds (pKa1=1.70-0.894σ, pKa2=6.92-0.934σ).
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32
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Raevsky OA, Grigorev VY, Polianczyk DE, Raevskaja OE, Dearden JC. Six global and local QSPR models of aqueous solubility at pH = 7.4 based on structural similarity and physicochemical descriptors. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2017; 28:661-676. [PMID: 28891683 DOI: 10.1080/1062936x.2017.1368704] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/14/2017] [Indexed: 06/07/2023]
Abstract
Aqueous solubility at pH = 7.4 is a very important property for medicinal chemists because this is the pH value of physiological media. The present work describes the application of three different methods (support vector machine (SVM), random forest (RF) and multiple linear regression (MLR)) and three local quantitative structure-property relationship (QSPR) models (regression corrected by nearest neighbours (RCNN), arithmetic mean property (AMP) and local regression property (LoReP)) to construct stable QSPRs with clear mechanistic interpretation. Our data set contained experimental values of aqueous solubility at pH = 7.4 of 387 chemicals (349 in the training set and 38 in the test set including 16 own measurements). The initial descriptor pool contained 210 physicochemical descriptors, calculated from the HYBOT, DRAGON, SYBYL and VolSurf+ programs. Six QSPRs with good statistics based on fundamentals of aqueous solubility and optimization of descriptor space were obtained. Those models have an RMSE close to experimental error (0.70), and are amenable to physical interpretation. The QSPR models developed in this study may be useful for medicinal chemists. Global MLR, RF and SVM models may be valuable for consideration of common factors that influence solubility. The RCNN, AMP and LoReP local models may be helpful for the optimization of aqueous solubility in small sets of related chemicals.
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Affiliation(s)
- O A Raevsky
- a Department of Computer-Aided Molecular Design , Russian Academy of Science , Chernogolovka , Russia
| | - V Y Grigorev
- a Department of Computer-Aided Molecular Design , Russian Academy of Science , Chernogolovka , Russia
| | - D E Polianczyk
- a Department of Computer-Aided Molecular Design , Russian Academy of Science , Chernogolovka , Russia
| | - O E Raevskaja
- a Department of Computer-Aided Molecular Design , Russian Academy of Science , Chernogolovka , Russia
| | - J C Dearden
- b School of Pharmacy and Biomolecular Sciences , Liverpool John Moores University , Liverpool , UK
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Ribeiro AR, Schmidt TC. Determination of acid dissociation constants (pK a) of cephalosporin antibiotics: Computational and experimental approaches. CHEMOSPHERE 2017; 169:524-533. [PMID: 27898325 DOI: 10.1016/j.chemosphere.2016.11.097] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 10/31/2016] [Accepted: 11/18/2016] [Indexed: 05/21/2023]
Abstract
Cefapirin (CEPA) and ceftiofur (CEF) are two examples of widely used veterinarian cephalosporins presenting multiple ionization centers. However, the acid dissociation constants (pKa) of CEF are missing and experimental data about CEPA are rare. The same is true for many cephalosporins, where available data are either incomplete or even wrong. Environmentally relevant biotic and abiotic processes depend primordially on the antibiotic pH-dependent speciation. Consequently, this physicochemical parameter should be reliable, including the correct ionization center identification. In this direction, two experimental techniques, potentiometry and spectrophotometry, along with two well-known pKa predictors, Marvin and ACD/Percepta, were used to study the macro dissociation constants of CEPA and CEF. Additionally, the experimental dissociation constants of 14 cephalosporins available in the literature were revised, compiled and compared with data obtained in silico. Only one value was determined experimentally for CEF (2.68 ± 0.05), which was associated to the carboxylic acid group deprotonation. For CEPA two values were obtained experimentally: 2.74 ± 0.01 for the carboxylic acid deprotonation and 5.13 ± 0.01 for the pyridinium ring deprotonation. In general, experimentally obtained values agree with the in silico predicted data (ACD/Percepta RMSE: 0.552 and Marvin RMSE: 0.706, n = 88). However, for cephalosporins having imine and aminothiazole groups structurally close, Marvin presented problems in pKa predictions. For the biological and environmental fate and effect discussion, it is important to recognize that CEPA and CEF, as well as many other cephalosporins, are present as anionic species in the biologic and environmentally relevant pH values of 6-7.5.
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Affiliation(s)
- Alyson R Ribeiro
- Instrumental Analytical Chemistry and Centre of Water and Environmental Research (ZWU), University of Duisburg-Essen, Universitätsstraße 5, 45141, Essen, Germany.
| | - Torsten C Schmidt
- Instrumental Analytical Chemistry and Centre of Water and Environmental Research (ZWU), University of Duisburg-Essen, Universitätsstraße 5, 45141, Essen, Germany.
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Spassov VZ, Yan L. A pH-dependent computational approach to the effect of mutations on protein stability. J Comput Chem 2016; 37:2573-87. [PMID: 27634390 DOI: 10.1002/jcc.24482] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/01/2016] [Accepted: 08/14/2016] [Indexed: 11/07/2022]
Abstract
This article describes a novel software implementation for high-throughput scanning mutagenesis with a focus on protein stability. The approach combines molecular mechanics calculations with calculations of protein ionization and a Gaussian-chain model of electrostatic interactions in unfolded state. Comprehensive testing demonstrates a state-of-the-art accuracy for predicted free energy differences on single, double, and triple mutations with a correlation coefficient R above 0.7, which takes about 1.5 min per mutation on a single CPU. Unlike most of existing in silico methods for fast mutagenesis, the stability changes are reported as a continuous function of solution pH for wide pH intervals. We also propose a novel in silico strategy for searching stabilized protein variants that is based on combinatorial scanning mutagenesis using representative amino acid types. Our in silico predictions are in excellent agreement with the hyper-stabilized variants of mesophilic cold shock protein found using the Proside method of direct evolution. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Velin Z Spassov
- BIOVIA, Dassault Systemes, 5005 Wateridge Vista Drive, San Diego, California, 92121.
| | - Lisa Yan
- BIOVIA, Dassault Systemes, 5005 Wateridge Vista Drive, San Diego, California, 92121
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35
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Awoonor-Williams E, Rowley CN. Evaluation of Methods for the Calculation of the pKa of Cysteine Residues in Proteins. J Chem Theory Comput 2016; 12:4662-73. [DOI: 10.1021/acs.jctc.6b00631] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ernest Awoonor-Williams
- Department of Chemistry, Memorial University of Newfoundland, St.
John’s, Newfoundland and Labrador A1B 3X9, Canada
| | - Christopher N. Rowley
- Department of Chemistry, Memorial University of Newfoundland, St.
John’s, Newfoundland and Labrador A1B 3X9, Canada
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36
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Rossini E, Netz RR, Knapp EW. Computing pKa Values in Different Solvents by Electrostatic Transformation. J Chem Theory Comput 2016; 12:3360-9. [DOI: 10.1021/acs.jctc.6b00446] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Emanuele Rossini
- Institute
of Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstrasse
36a, D-14195 Berlin, Germany
| | - Roland R. Netz
- Department
of Physics, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
| | - Ernst-Walter Knapp
- Institute
of Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstrasse
36a, D-14195 Berlin, Germany
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37
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Yu D, Du R, Xiao JC. pK
a prediction for acidic phosphorus-containing compounds using multiple linear regression with computational descriptors. J Comput Chem 2016; 37:1668-71. [DOI: 10.1002/jcc.24381] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/12/2016] [Accepted: 03/05/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Donghai Yu
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences; Shanghai China
| | - Ruobing Du
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences; Shanghai China
| | - Ji-Chang Xiao
- Key Laboratory of Organofluorine Chemistry; Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences; Shanghai China
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38
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Raevsky OA. CNS Multiparameter Optimization Approach: Is it in Accordance with Occam’s Razor Principle? Mol Inform 2016; 35:94-8. [DOI: 10.1002/minf.201500109] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 12/11/2015] [Indexed: 01/30/2023]
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39
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Nieto-Draghi C, Fayet G, Creton B, Rozanska X, Rotureau P, de Hemptinne JC, Ungerer P, Rousseau B, Adamo C. A General Guidebook for the Theoretical Prediction of Physicochemical Properties of Chemicals for Regulatory Purposes. Chem Rev 2015; 115:13093-164. [PMID: 26624238 DOI: 10.1021/acs.chemrev.5b00215] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Carlos Nieto-Draghi
- IFP Energies nouvelles , 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Guillaume Fayet
- INERIS, Parc Technologique Alata, BP2 , 60550 Verneuil-en-Halatte, France
| | - Benoit Creton
- IFP Energies nouvelles , 1 et 4 avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Xavier Rozanska
- Materials Design S.A.R.L. , 18, rue de Saisset, 92120 Montrouge, France
| | - Patricia Rotureau
- INERIS, Parc Technologique Alata, BP2 , 60550 Verneuil-en-Halatte, France
| | | | - Philippe Ungerer
- Materials Design S.A.R.L. , 18, rue de Saisset, 92120 Montrouge, France
| | - Bernard Rousseau
- Laboratoire de Chimie-Physique, Université Paris Sud , UMR 8000 CNRS, Bât. 349, 91405 Orsay Cedex, France
| | - Carlo Adamo
- Institut de Recherche Chimie Paris, PSL Research University, CNRS, Chimie Paristech , 11 rue P. et M. Curie, F-75005 Paris, France.,Institut Universitaire de France , 103 Boulevard Saint Michel, F-75005 Paris, France
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40
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Jain R, Kumar R, Kumar S, Chhabra R, Agarwal MC, Kumar R. Analysis of the pH-dependent stability and millisecond folding kinetics of horse cytochrome c. Arch Biochem Biophys 2015; 585:52-63. [DOI: 10.1016/j.abb.2015.09.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 09/10/2015] [Accepted: 09/14/2015] [Indexed: 11/26/2022]
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41
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Semenov VE, Zueva IV, Mukhamedyarov MA, Lushchekina SV, Kharlamova AD, Petukhova EO, Mikhailov AS, Podyachev SN, Saifina LF, Petrov KA, Minnekhanova OA, Zobov VV, Nikolsky EE, Masson P, Reznik VS. 6-Methyluracil Derivatives as Bifunctional Acetylcholinesterase Inhibitors for the Treatment of Alzheimer's Disease. ChemMedChem 2015; 10:1863-74. [DOI: 10.1002/cmdc.201500334] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Vyacheslav E. Semenov
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | - Irina V. Zueva
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
- Kazan Federal University; Kremlevskaya str. 18 Kazan 420008 Russia
| | | | - Sofya V. Lushchekina
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
- N.M. Emanuel Institute of Biochemical Physics; Kosygin str. 4 Moscow 119991 Russia
| | - Alexandra D. Kharlamova
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | | | - Anatoly S. Mikhailov
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | - Sergey N. Podyachev
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | - Lilya F. Saifina
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | - Konstantin A. Petrov
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
- Kazan Federal University; Kremlevskaya str. 18 Kazan 420008 Russia
- Kazan Institute of Biochemistry & Biophysics; Russian Academy of Sciences; Lobachevsky str. 2/31 Kazan 420111 Russia
| | - Oksana A. Minnekhanova
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
| | - Vladimir V. Zobov
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
- Kazan Federal University; Kremlevskaya str. 18 Kazan 420008 Russia
| | - Evgeny E. Nikolsky
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
- Kazan Federal University; Kremlevskaya str. 18 Kazan 420008 Russia
- Kazan State Medical University; Butlerov str. 49 Kazan 420012 Russia
- Kazan Institute of Biochemistry & Biophysics; Russian Academy of Sciences; Lobachevsky str. 2/31 Kazan 420111 Russia
| | - Patrick Masson
- Kazan Federal University; Kremlevskaya str. 18 Kazan 420008 Russia
| | - Vladimir S. Reznik
- A.E. Arbuzov Institute of Organic & Physical Chemistry, Kazan Scientific Center; Russian Academy of Sciences; Arbuzov str. 8 Kazan 420088 Russia
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42
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Mamy L, Patureau D, Barriuso E, Bedos C, Bessac F, Louchart X, Martin-laurent F, Miege C, Benoit P. Prediction of the Fate of Organic Compounds in the Environment From Their Molecular Properties: A Review. CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY 2015; 45:1277-1377. [PMID: 25866458 PMCID: PMC4376206 DOI: 10.1080/10643389.2014.955627] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A comprehensive review of quantitative structure-activity relationships (QSAR) allowing the prediction of the fate of organic compounds in the environment from their molecular properties was done. The considered processes were water dissolution, dissociation, volatilization, retention on soils and sediments (mainly adsorption and desorption), degradation (biotic and abiotic), and absorption by plants. A total of 790 equations involving 686 structural molecular descriptors are reported to estimate 90 environmental parameters related to these processes. A significant number of equations was found for dissociation process (pKa), water dissolution or hydrophobic behavior (especially through the KOW parameter), adsorption to soils and biodegradation. A lack of QSAR was observed to estimate desorption or potential of transfer to water. Among the 686 molecular descriptors, five were found to be dominant in the 790 collected equations and the most generic ones: four quantum-chemical descriptors, the energy of the highest occupied molecular orbital (EHOMO) and the energy of the lowest unoccupied molecular orbital (ELUMO), polarizability (α) and dipole moment (μ), and one constitutional descriptor, the molecular weight. Keeping in mind that the combination of descriptors belonging to different categories (constitutional, topological, quantum-chemical) led to improve QSAR performances, these descriptors should be considered for the development of new QSAR, for further predictions of environmental parameters. This review also allows finding of the relevant QSAR equations to predict the fate of a wide diversity of compounds in the environment.
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Affiliation(s)
- Laure Mamy
- INRA-AgroParisTech, UMR 1402 ECOSYS (Ecologie Fonctionnelle et Ecotoxicologie des Agroécosystèmes), Versailles, France
| | - Dominique Patureau
- INRA, UR 0050 LBE (Laboratoire de Biotechnologie de l’Environnement), Narbonne, France
| | - Enrique Barriuso
- INRA-AgroParisTech, UMR 1402 ECOSYS (Ecologie Fonctionnelle et Ecotoxicologie des Aroécosystèmes), Thiverval-Grignon, France
| | - Carole Bedos
- INRA-AgroParisTech, UMR 1402 ECOSYS (Ecologie Fonctionnelle et Ecotoxicologie des Aroécosystèmes), Thiverval-Grignon, France
| | - Fabienne Bessac
- Université de Toulouse – INPT, Ecole d’Ingénieurs de Purpan – UPS, IRSAMCLaboratoire de Chimie et Physique Quantiques – CNRS, UMR 5626, Toulouse, France
| | - Xavier Louchart
- INRA, UMR 1221 LISAH (Laboratoire d’étude des Interactions Sol - Agrosystème – Hydrosystème), Montpellier, France
| | | | | | - Pierre Benoit
- INRA-AgroParisTech, UMR 1402 ECOSYS (Ecologie Fonctionnelle et Ecotoxicologie des Aroécosystèmes), Thiverval-Grignon, France
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Geidl S, Svobodová Vařeková R, Bendová V, Petrusek L, Ionescu CM, Jurka Z, Abagyan R, Koča J. How Does the Methodology of 3D Structure Preparation Influence the Quality of pKa Prediction? J Chem Inf Model 2015; 55:1088-97. [PMID: 26010215 DOI: 10.1021/ci500758w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The acid dissociation constant is an important molecular property, and it can be successfully predicted by Quantitative Structure-Property Relationship (QSPR) models, even for in silico designed molecules. We analyzed how the methodology of in silico 3D structure preparation influences the quality of QSPR models. Specifically, we evaluated and compared QSPR models based on six different 3D structure sources (DTP NCI, Pubchem, Balloon, Frog2, OpenBabel, and RDKit) combined with four different types of optimization. These analyses were performed for three classes of molecules (phenols, carboxylic acids, anilines), and the QSPR model descriptors were quantum mechanical (QM) and empirical partial atomic charges. Specifically, we developed 516 QSPR models and afterward systematically analyzed the influence of the 3D structure source and other factors on their quality. Our results confirmed that QSPR models based on partial atomic charges are able to predict pKa with high accuracy. We also confirmed that ab initio and semiempirical QM charges provide very accurate QSPR models and using empirical charges based on electronegativity equalization is also acceptable, as well as advantageous, because their calculation is very fast. On the other hand, Gasteiger-Marsili empirical charges are not applicable for pKa prediction. We later found that QSPR models for some classes of molecules (carboxylic acids) are less accurate. In this context, we compared the influence of different 3D structure sources. We found that an appropriate selection of 3D structure source and optimization method is essential for the successful QSPR modeling of pKa. Specifically, the 3D structures from the DTP NCI and Pubchem databases performed the best, as they provided very accurate QSPR models for all the tested molecular classes and charge calculation approaches, and they do not require optimization. Also, Frog2 performed very well. Other 3D structure sources can also be used but are not so robust, and an unfortunate combination of molecular class and charge calculation approach can produce weak QSPR models. Additionally, these 3D structures generally need optimization in order to produce good quality QSPR models.
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Affiliation(s)
- Stanislav Geidl
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Radka Svobodová Vařeková
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Veronika Bendová
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Lukáš Petrusek
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Crina-Maria Ionescu
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Zdeněk Jurka
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
| | - Ruben Abagyan
- ‡Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, 9500 Gilman Drive, MC 0657, San Diego, California 92161, United States
| | - Jaroslav Koča
- †National Centre for Biomolecular Research, Faculty of Science, and CEITEC - Central European Institute of Technology, Masaryk University Brno, Kamenice 5, 625 00 Brno-Bohunice, Czech Republic
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44
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Zevatskiy YE, Ruzanov DO, Samoylov DV. Photometric method for determination of acidity constants through integral spectra analysis. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 141:161-168. [PMID: 25668697 DOI: 10.1016/j.saa.2015.01.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 01/01/2015] [Accepted: 01/15/2015] [Indexed: 06/04/2023]
Abstract
An express method for determination of acidity constants of organic acids, based on the analysis of the integral transmittance vs. pH dependence is developed. The integral value is registered as a photocurrent of photometric device simultaneously with potentiometric titration. The proposed method allows to obtain pKa using only simple and low-cost instrumentation. The optical part of the experimental setup has been optimized through the exclusion of the monochromator device. Thus it only takes 10-15 min to obtain one pKa value with the absolute error of less than 0.15 pH units. Application limitations and reliability of the method have been tested for a series of organic acids of various nature.
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Affiliation(s)
- Yuriy Eduardovich Zevatskiy
- Saint-Petersburg State University of Technology & Design, Bolshaya Morskaya str. 18, Saint-Petersburg, 191186, Russia
| | - Daniil Olegovich Ruzanov
- Saint-Petersburg State Institute of Technology (Technical University), Moskovskiy ave., 26, Saint-Petersburg, 190013, Russia.
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45
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Seybold PG, Shields GC. Computational estimation of pKa
values. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2015. [DOI: 10.1002/wcms.1218] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Paul G. Seybold
- Departments of Chemistry and Biochemistry; Wright State University; Dayton OH USA
| | - George C. Shields
- Department of Chemistry and College of Arts & Sciences; Bucknell University; Lewisburg PA USA
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46
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Zhu L, Zhang Y, Yang J, Wang Y, Zhang J, Zhao Y, Dong W. Prediction of the pharmacokinetics and tissue distribution of levofloxacin in humans based on an extrapolated PBPK model. Eur J Drug Metab Pharmacokinet 2015; 41:395-402. [PMID: 25753830 DOI: 10.1007/s13318-015-0271-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 02/23/2015] [Indexed: 12/27/2022]
Abstract
This study developed a physiologically based pharmacokinetic (PBPK) model in intraabdominally infected rats and extrapolated it to humans to predict the levofloxacin pharmacokinetics and penetration into tissues. Twelve male rats with intraabdominal infections induced by Escherichia coli received a single dose of 50 mg/kg body weight of levofloxacin. Blood plasma was collected at 5, 10, 20, 30, 60, 120, 240, 480 and 1440 min after injection, respectively. A PBPK model was developed in rats and extrapolated to humans using GastroPlus software. The predictions were assessed by comparing predictions and observations. In the plasma concentration-versus-time profile of levofloxacin in rats, C max was 23.570 μg/ml at 5 min after intravenous injection, and t1/2 was 2.38 h. The plasma concentration and kinetics in humans were predicted and validated by the observed data. Levofloxacin penetrated and accumulated with high concentrations in the heart, liver, kidney, spleen, muscle and skin tissues in humans. The predicted tissue-to-plasma concentration ratios in abdominal viscera were between 1.9 and 2.3. When rat plasma concentrations were known, extrapolation of a PBPK model was a method to predict the drug pharmacokinetics and penetration in humans. Levofloxacin had good penetration into the liver, kidney and spleen as well as other tissues in humans. This pathological model extrapolation may provide a reference for the study of antiinfective PK/PD. In our study, levofloxacin penetrated well into abdominal organs. Also ADR monitoring should be implemented when using levofloxacin.
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Affiliation(s)
- Liqin Zhu
- Pharmacy Department, Tianjin First Center Hospital, No. 24 Fukang Road, Nankai District, Tianjin, 300192, China.
| | - Yuan Zhang
- Pharmacy Department, Tianjin First Center Hospital, No. 24 Fukang Road, Nankai District, Tianjin, 300192, China
| | - Jianwei Yang
- Tianjin Medical University, Tianjin, 300070, China
| | | | - Jianlei Zhang
- Pharmacy Department, Tianjin First Center Hospital, No. 24 Fukang Road, Nankai District, Tianjin, 300192, China
| | - Yuanyuan Zhao
- The 153 Central Hospital of the Chinese People's Liberation Army, Henan, 450000, China
| | - Weilin Dong
- Tianjin Medical University, Tianjin, 300070, China
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47
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Kögel JF, Linder T, Schröder FG, Sundermeyer J, Goll SK, Himmel D, Krossing I, Kütt K, Saame J, Leito I. Fluoro- and Perfluoralkylsulfonylpentafluoroanilides: Synthesis and Characterization of NH Acids for Weakly Coordinating Anions and Their Gas-Phase and Solution Acidities. Chemistry 2015; 21:5769-82. [DOI: 10.1002/chem.201405391] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Indexed: 11/07/2022]
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48
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Zhu L, Yang J, Zhang Y, Wang Y, Zhang J, Zhao Y, Dong W. Prediction of Pharmacokinetics and Penetration of Moxifloxacin in Human with Intra-Abdominal Infection Based on Extrapolated PBPK Model. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2015; 19:99-104. [PMID: 25729270 PMCID: PMC4342742 DOI: 10.4196/kjpp.2015.19.2.99] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 11/25/2014] [Accepted: 12/17/2014] [Indexed: 11/30/2022]
Abstract
The aim of this study is to develop a physiologically based pharmacokinetic (PBPK) model in intra-abdominal infected rats, and extrapolate it to human to predict moxifloxacin pharmacokinetics profiles in various tissues in intra-abdominal infected human. 12 male rats with intra-abdominal infections, induced by Escherichia coli, received a single dose of 40 mg/kg body weight of moxifloxacin. Blood plasma was collected at 5, 10, 20, 30, 60, 120, 240, 480, 1440 min after drug injection. A PBPK model was developed in rats and extrapolated to human using GastroPlus software. The predictions were assessed by comparing predictions and observations. In the plasma concentration versus time profile of moxifloxcinin rats, Cmax was 11.151 µg/mL at 5 min after the intravenous injection and t1/2 was 2.936 h. Plasma concentration and kinetics in human were predicted and compared with observed datas. Moxifloxacin penetrated and accumulated with high concentrations in redmarrow, lung, skin, heart, liver, kidney, spleen, muscle tissues in human with intra-abdominal infection. The predicted tissue to plasma concentration ratios in abdominal viscera were between 1.1 and 2.2. When rat plasma concentrations were known, extrapolation of a PBPK model was a method to predict drug pharmacokinetics and penetration in human. Moxifloxacin has a good penetration into liver, kidney, spleen, as well as other tissues in intra-abdominal infected human. Close monitoring are necessary when using moxifloxacin due to its high concentration distribution. This pathological model extrapolation may provide reference to the PK/PD study of antibacterial agents.
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Affiliation(s)
- LiQin Zhu
- Tianjin First Central Hospital, Tianjin 300192, China
| | - JianWei Yang
- Tianjin Medical University, Tianjin 300070, China
| | - Yuan Zhang
- Tianjin First Central Hospital, Tianjin 300192, China. ; Tianjin Medical University, Tianjin 300070, China
| | | | - JianLei Zhang
- Tianjin First Central Hospital, Tianjin 300192, China
| | - YuanYuan Zhao
- The 153 Central Hospital of the Chinese People's Liberation Army, Henan 450000, China
| | - WeiLin Dong
- Tianjin Medical University, Tianjin 300070, China
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49
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Alkorta I, Popelier PLA. Linear free-energy relationships between a single gas-phase ab initio equilibrium bond length and experimental pKa values in aqueous solution. Chemphyschem 2014; 16:465-9. [PMID: 25382620 DOI: 10.1002/cphc.201402711] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Indexed: 11/11/2022]
Abstract
Remarkably simple yet effective linear free energy relationships were discovered between a single ab initio computed bond length in the gas phase and experimental pKa values in aqueous solution. The formation of these relationships is driven by chemical features such as functional groups, meta/para substitution and tautomerism. The high structural content of the ab initio bond length makes a given data set essentially divide itself into high correlation subsets (HCSs). Surprisingly, all molecules in a given high correlation subset share the same conformation in the gas phase. Here we show that accurate pKa values can be predicted from such HCSs. This is achieved within an accuracy of 0.2 pKa units for 5 drug molecules.
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Affiliation(s)
- Ibon Alkorta
- Instituto de Química Médica (IQM-CSIC), Juan de la Cierva, 3, 28006 Madrid (Spain).
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50
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Orliac A, Routier J, Charvillon FB, Sauer WHB, Bombrun A, Kulkarni SS, Pardo DG, Cossy J. Enantioselective synthesis and physicochemical properties of libraries of 3-amino- and 3-amidofluoropiperidines. Chemistry 2014; 20:3813-24. [PMID: 24532344 DOI: 10.1002/chem.201302423] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 11/06/2013] [Indexed: 11/07/2022]
Abstract
The enantioselective syntheses of 3-amino-5-fluoropiperidines and 3-amino-5,5-difluoropiperidines were developed using the ring enlargement of prolinols to access libraries of 3-amino- and 3-amidofluoropiperidines. The study of the physicochemical properties revealed that fluorine atom(s) decrease(s) the pKa and modulate(s) the lipophilicity of 3-aminopiperidines. The relative stereochemistry of the fluorine atoms with the amino groups at C3 on the piperidine core has a small effect on the pKa due to conformationnal modifications induced by fluorine atom(s). In the protonated forms, the C-F bond is in an axial position due to a dipole-dipole interaction between the N-H(+) and C-F bonds. Predictions of the physicochemical properties using common software appeared to be limited to determine correct values of pKa and/or differences of pKa between cis- and trans-3-amino-5-fluoropiperidines.
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Affiliation(s)
- Aurélie Orliac
- Laboratoire de Chimie Organique, ESPCI ParisTech, 10 Rue Vauquelin, 75231 Paris Cedex 05 (France), Fax: (+33) 1-40-79-46-60
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