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Pal R, Patra SG, Chattaraj PK. Quantitative Structure-Toxicity Relationship in Bioactive Molecules from a Conceptual DFT Perspective. Pharmaceuticals (Basel) 2022; 15:1383. [PMID: 36355555 PMCID: PMC9695291 DOI: 10.3390/ph15111383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/01/2022] [Accepted: 11/07/2022] [Indexed: 10/29/2023] Open
Abstract
The preclinical drug discovery stage often requires a large amount of costly and time-consuming experiments using huge sets of chemical compounds. In the last few decades, this process has undergone significant improvements by the introduction of quantitative structure-activity relationship (QSAR) modelling that uses a certain percentage of experimental data to predict the biological activity/property of compounds with similar structural skeleton and/or containing a particular functional group(s). The use of machine learning tools along with it has made life even easier for pharmaceutical researchers. Here, we discuss the toxicity of certain sets of bioactive compounds towards Pimephales promelas and Tetrahymena pyriformis in terms of the global conceptual density functional theory (CDFT)-based descriptor, electrophilicity index (ω). We have compared the results with those obtained by using the commonly used hydrophobicity parameter, logP (where P is the n-octanol/water partition coefficient), considering the greater ease of computing the ω descriptor. The Human African trypanosomiasis (HAT) curing activity of 32 pyridyl benzamide derivatives is also studied against Tryphanosoma brucei. In this review article, we summarize these multiple linear regression (MLR)-based QSAR studies in terms of electrophilicity (ω, ω2) and hydrophobicity (logP, (logP)2) parameters.
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Affiliation(s)
- Ranita Pal
- Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Shanti Gopal Patra
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Pratim Kumar Chattaraj
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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Web-Based Quantitative Structure-Activity Relationship Resources Facilitate Effective Drug Discovery. Top Curr Chem (Cham) 2021; 379:37. [PMID: 34554348 DOI: 10.1007/s41061-021-00349-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 08/17/2021] [Indexed: 12/28/2022]
Abstract
Traditional drug discovery effectively contributes to the treatment of many diseases but is limited by high costs and long cycles. Quantitative structure-activity relationship (QSAR) methods were introduced to evaluate the activity of compounds virtually, which saves the significant cost of determining the activities of the compounds experimentally. Over the past two decades, many web tools for QSAR modeling with various features have been developed to facilitate the usage of QSAR methods. These web tools significantly reduce the difficulty of using QSAR and indirectly promote drug discovery. However, there are few comprehensive summaries of these QSAR tools, and researchers may have difficulty determining which tool to use. Hence, we systematically surveyed the mainstream web tools for QSAR modeling. This work may guide researchers in choosing appropriate web tools for developing QSAR models, and may also help develop more bioinformatics tools based on these existing resources. For nonprofessionals, we also hope to make more people aware of QSAR methods and expand their use.
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Baybekov S, Marcou G, Ramos P, Saurel O, Galzi JL, Varnek A. DMSO Solubility Assessment for Fragment-Based Screening. Molecules 2021; 26:3950. [PMID: 34203441 PMCID: PMC8271413 DOI: 10.3390/molecules26133950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 11/16/2022] Open
Abstract
In this paper, we report comprehensive experimental and chemoinformatics analyses of the solubility of small organic molecules ("fragments") in dimethyl sulfoxide (DMSO) in the context of their ability to be tested in screening experiments. Here, DMSO solubility of 939 fragments has been measured experimentally using an NMR technique. A Support Vector Classification model was built on the obtained data using the ISIDA fragment descriptors. The analysis revealed 34 outliers: experimental issues were retrospectively identified for 28 of them. The updated model performs well in 5-fold cross-validation (balanced accuracy = 0.78). The datasets are available on the Zenodo platform (DOI:10.5281/zenodo.4767511) and the model is available on the website of the Laboratory of Chemoinformatics.
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Affiliation(s)
- Shamkhal Baybekov
- Laboratoire de Chémoinformatique UMR 7140 CNRS, Institut Le Bel, University of Strasbourg, 4 Rue Blaise Pascal, 67081 Strasbourg, France; (S.B.); (G.M.)
| | - Gilles Marcou
- Laboratoire de Chémoinformatique UMR 7140 CNRS, Institut Le Bel, University of Strasbourg, 4 Rue Blaise Pascal, 67081 Strasbourg, France; (S.B.); (G.M.)
| | - Pascal Ramos
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse CNRS, UPS, 205 Route de Narbonne, 31077 Toulouse, France; (P.R.); (O.S.)
| | - Olivier Saurel
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse CNRS, UPS, 205 Route de Narbonne, 31077 Toulouse, France; (P.R.); (O.S.)
| | - Jean-Luc Galzi
- Biotechnologie et Signalisation Cellulaire UMR 7242 CNRS, École Supérieure de Biotechnologie de Strasbourg, University of Strasbourg, 300 Boulevard Sébastien Brant, 67412 Illkirch, France;
- ChemBioFrance—Chimiothèque Nationale UAR3035, 8 Rue de L’école Normale, CEDEX 05, 34296 Montpellier, France
| | - Alexandre Varnek
- Laboratoire de Chémoinformatique UMR 7140 CNRS, Institut Le Bel, University of Strasbourg, 4 Rue Blaise Pascal, 67081 Strasbourg, France; (S.B.); (G.M.)
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Aalizadeh R, Nika MC, Thomaidis NS. Development and application of retention time prediction models in the suspect and non-target screening of emerging contaminants. JOURNAL OF HAZARDOUS MATERIALS 2019; 363:277-285. [PMID: 30312924 DOI: 10.1016/j.jhazmat.2018.09.047] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/16/2018] [Accepted: 09/17/2018] [Indexed: 05/13/2023]
Abstract
Hydrophilic interaction liquid chromatography (HILIC) and reversed phase LC (RPLC) coupled to high resolution mass spectrometry (HRMS) are widely used for the identification of suspects and unknown compounds in the environment. For the identification of unknowns, apart from mass accuracy and isotopic fitting, retention time (tR) and MS/MS spectra evaluation is required. In this context, a novel comprehensive workflow was developed to study the tR behavior of large groups of emerging contaminants using Quantitative Structure-Retention Relationships (QSRR). 682 compounds were analyzed by HILIC-HRMS in positive Electrospray Ionization mode (ESI). Moreover, an extensive dataset was built for RPLC-HRMS including 1830 and 308 compounds for positive and negative ESI, respectively. Support Vector Machines (SVM) was used to model the tR data. The applicability domains of the models were studied by Monte Carlo Sampling (MCS) methods. The MCS method was also used to calculate the acceptable error windows for the predicted tR from various LC conditions. This paper provides validated models for predicting tR in HILIC/RPLC-HRMS platforms to facilitate identification of new emerging contaminants by suspect and non-target HRMS screening, and were applied for the identification of transformation products (TPs) of emerging contaminants and biocides in wastewater and sludge.
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Affiliation(s)
- Reza Aalizadeh
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zographou, 15771, Athens, Greece
| | - Maria-Christina Nika
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zographou, 15771, Athens, Greece
| | - Nikolaos S Thomaidis
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zographou, 15771, Athens, Greece.
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Assessment of tautomer distribution using the condensed reaction graph approach. J Comput Aided Mol Des 2018; 32:401-414. [DOI: 10.1007/s10822-018-0101-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 01/18/2018] [Indexed: 02/07/2023]
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Support vector regression-guided unravelling: antioxidant capacity and quantitative structure-activity relationship predict reduction and promotion effects of flavonoids on acrylamide formation. Sci Rep 2016; 6:32368. [PMID: 27586851 PMCID: PMC5009353 DOI: 10.1038/srep32368] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 08/08/2016] [Indexed: 11/29/2022] Open
Abstract
We used the support vector regression (SVR) approach to predict and unravel reduction/promotion effect of characteristic flavonoids on the acrylamide formation under a low-moisture Maillard reaction system. Results demonstrated the reduction/promotion effects by flavonoids at addition levels of 1–10000 μmol/L. The maximal inhibition rates (51.7%, 68.8% and 26.1%) and promote rates (57.7%, 178.8% and 27.5%) caused by flavones, flavonols and isoflavones were observed at addition levels of 100 μmol/L and 10000 μmol/L, respectively. The reduction/promotion effects were closely related to the change of trolox equivalent antioxidant capacity (ΔTEAC) and well predicted by triple ΔTEAC measurements via SVR models (R: 0.633–0.900). Flavonols exhibit stronger effects on the acrylamide formation than flavones and isoflavones as well as their O-glycosides derivatives, which may be attributed to the number and position of phenolic and 3-enolic hydroxyls. The reduction/promotion effects were well predicted by using optimized quantitative structure-activity relationship (QSAR) descriptors and SVR models (R: 0.926–0.994). Compared to artificial neural network and multi-linear regression models, SVR models exhibited better fitting performance for both TEAC-dependent and QSAR descriptor-dependent predicting work. These observations demonstrated that the SVR models are competent for predicting our understanding on the future use of natural antioxidants for decreasing the acrylamide formation.
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Aalizadeh R, Thomaidis NS, Bletsou AA, Gago-Ferrero P. Quantitative Structure-Retention Relationship Models To Support Nontarget High-Resolution Mass Spectrometric Screening of Emerging Contaminants in Environmental Samples. J Chem Inf Model 2016; 56:1384-98. [PMID: 27266383 DOI: 10.1021/acs.jcim.5b00752] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Reza Aalizadeh
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Nikolaos S Thomaidis
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Anna A Bletsou
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Pablo Gago-Ferrero
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
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Beiknejad D, Chaichi MJ, Fatemi MH. Prediction of photolysis half-lives of dihydroindolizines by genetic algorithm-multiple linear regression (GA-MLR). J PHYS ORG CHEM 2016. [DOI: 10.1002/poc.3540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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10
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Nontarget Analysis of Environmental Samples Based on Liquid Chromatography Coupled to High Resolution Mass Spectrometry (LC-HRMS). APPLICATIONS OF TIME-OF-FLIGHT AND ORBITRAP MASS SPECTROMETRY IN ENVIRONMENTAL, FOOD, DOPING, AND FORENSIC ANALYSIS 2016. [DOI: 10.1016/bs.coac.2016.01.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Camacho-Mendoza RL, Gutiérrez-Moreno E, Guzmán-Percástegui E, Aquino-Torres E, Cruz-Borbolla J, Rodríguez-Ávila JA, Alvarado-Rodríguez JG, Olvera-Neria O, Thangarasu P, Medina-Franco JL. Density Functional Theory and Electrochemical Studies: Structure–Efficiency Relationship on Corrosion Inhibition. J Chem Inf Model 2015; 55:2391-402. [DOI: 10.1021/acs.jcim.5b00385] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rosa L. Camacho-Mendoza
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - Evelin Gutiérrez-Moreno
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - Edmundo Guzmán-Percástegui
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - Eliazar Aquino-Torres
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - Julián Cruz-Borbolla
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - José A. Rodríguez-Ávila
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - José G. Alvarado-Rodríguez
- Área
Académica de Química, Universidad Autónoma del Estado de Hidalgo, Unidad Universitaria, km 4.5 Carretera Pachuca-Tulancingo, C.P. 42184, Pachuca-Hidalgo, México
| | - Oscar Olvera-Neria
- Área
de Física Atómica Molecular Aplicada (FAMA), CBI, Universidad Autónoma Metropolitana-Azcapotzalco, Av. San Pablo 180, Col. Reynosa, Mexico City, C.P. 02200, México
| | - Pandiyan Thangarasu
- Facultad
de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City, C.P. 04510, México
| | - José L. Medina-Franco
- Facultad
de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City, C.P. 04510, México
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Galzi JL, Ruggiu F, Gizzi P, Didier B. [Quality control of chemical libraries]. Med Sci (Paris) 2015; 31:660-6. [PMID: 26152171 DOI: 10.1051/medsci/20153106020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The complete sequence of the human genome has been deciphered at the dawn of the new century. This historic event immediately challenged researchers with new needs both in terms of concepts and of working methods. Each scientific community considered how it could tackle these new challenges and it quickly became clear that using small chemical molecules would help discovering and characterizing the function of new proteins. The importance of the genes that the encode new proteins could thus be established in cells, organs and whole organisms. At the initiative of a handful of researchers, French chemists have organized the collection of their molecules and provided them to biologists. By doing so they killed two birds with one stone: on the one hand they created a unique opportunity to add value to their molecules by creating the first academic chemical library, and on the other hand they stimulated the launch of biologically active molecules discovery programs by biologists from the academic sector. It was necessary, however, to raise many compounds and ensure consistent quality control, which quickly became a priority for the chemical libraries to become reliable tools.
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Affiliation(s)
- Jean-Luc Galzi
- CNRS-Unistra UMR 7242, biotechnologies et signalisation cellulaire, 300, boulevard Sébastien Brant, CS 10413, 67412 Illkirch, France
| | - Fiorella Ruggiu
- CNRS-Unistra UMR 7140, laboratoire de chémoinformatique, 67000 Strasbourg, France
| | - Patrick Gizzi
- CNRS-Unistra UMR 7242, biotechnologies et signalisation cellulaire, 300, boulevard Sébastien Brant, CS 10413, 67412 Illkirch, France
| | - Bruno Didier
- CNRS-Unistra UMR 7200, laboratoire d'innovation thérapeutique, 67412 Illkirch, France
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Kaneko H, Funatsu K. Strategy of Structure Generation within Applicability Domains with One-Class Support Vector Machine. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2015. [DOI: 10.1246/bcsj.20150054] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Hiromasa Kaneko
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo
| | - Kimito Funatsu
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo
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Fleury L, Faux C, Santos C, Ballereau S, Génisson Y, Ausseil F. Development of a CERT START Domain-Ceramide HTRF Binding Assay and Application to Pharmacological Studies and Screening. ACTA ACUST UNITED AC 2015; 20:779-87. [PMID: 25716975 DOI: 10.1177/1087057115573402] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 01/09/2015] [Indexed: 11/16/2022]
Abstract
Sphingomyelin (SM) metabolism deregulation was recently associated with cell metastasis and chemoresistance, and several pharmacological strategies targeting SM metabolism have emerged. The ceramide (Cer) generated in the endoplasmic reticulum (ER) is transferred to the Golgi apparatus to be transformed into SM. CERamide Transfer (CERT) protein is responsible for the nonvesicular trafficking of Cer to Golgi. Blocking the CERT-mediated ER-to-Golgi Cer transfer is an interesting antioncogenic therapeutic approach. Here, we developed a protein-lipid interaction assay for the identification of new CERT-Cer interaction inhibitors. Frequently used for protein-protein interaction by enzymatic and analyte dosage assays, homogeneous time-resolved fluorescence technology was adapted for the first time to a lipid-protein binding assay. This test was developed for high-throughput screening, and a library of 672 molecules was screened. Seven hits were identified, and their inhibitory effect quantified by EC50 measurements showed binding inhibition three orders of magnitude more potent than that of HPA12, the unique known CERT antagonist to date. Each compound was tested on an independent test, confirming its high affinity and pharmacological potential.
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Affiliation(s)
| | - Céline Faux
- Unité de Service et de Recherche CNRS, Toulouse, France
| | - Cécile Santos
- LSPCMIB, CNRS-Université Paul Sabatier-Toulouse III, Toulouse, France
| | | | - Yves Génisson
- LSPCMIB, CNRS-Université Paul Sabatier-Toulouse III, Toulouse, France
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Computational chemogenomics: is it more than inductive transfer? J Comput Aided Mol Des 2014; 28:597-618. [PMID: 24771144 DOI: 10.1007/s10822-014-9743-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 04/11/2014] [Indexed: 10/25/2022]
Abstract
High-throughput assays challenge us to extract knowledge from multi-ligand, multi-target activity data. In QSAR, weights are statically fitted to each ligand descriptor with respect to a single endpoint or target. However, computational chemogenomics (CG) has demonstrated benefits of learning from entire grids of data at once, rather than building target-specific QSARs. A possible reason for this is the emergence of inductive knowledge transfer (IT) between targets, providing statistical robustness to the model, with no assumption about the structure of the targets. Relevant protein descriptors in CG should allow one to learn how to dynamically adjust ligand attribute weights with respect to protein structure. Hence, models built through explicit learning (EL) by including protein information, while benefitting from IT enhancement, should provide additional predictive capability, notably for protein deorphanization. This interplay between IT and EL in CG modeling is not sufficiently studied. While IT is likely to occur irrespective of the injected target information, it is not clear whether and when boosting due to EL may occur. EL is only possible if protein description is appropriate to the target set under investigation. The key issue here is the search for evidence of genuine EL exceeding expectations based on pure IT. We explore the problem in the context of Support Vector Regression, using more than 9,400 pKi values of 31 GPCRs, where compound-protein interactions are represented by the concatenation of vectorial descriptions of compounds and proteins. This provides a unified framework to generate both IT-enhanced and potentially EL-enabled models, where the difference is toggled by supplied protein information. For EL-enabled models, protein information includes genuine protein descriptors such as typical sequence-based terms, but also the experimentally determined affinity cross-correlation fingerprints. These latter benchmark the expected behavior of a quasi-ideal descriptor capturing the actual functional protein-protein relatedness, and therefore thought to be the most likely to enable EL. EL- and IT-based methods were benchmarked alongside classical QSAR, with respect to cross-validation and deorphanization challenges. A rational method for projecting benchmarked methodologies into a strategy space is given, in the aims that the projection will provide directions for the types of molecule designs possible using a given methodology. While EL-enabled strategies outperform classical QSARs and favorably compare to similar published results, they are, in all respects evaluated herein, not strongly distinguished from IT-enhanced models. Moreover, EL-enabled strategies failed to prove superior in deorphanization challenges. Therefore, this paper raises caution that, contrary to common belief and intuitive expectation, the benefits of chemogenomics models over classical QSAR are quite possibly due less to the injection of protein-related information, and rather impacted more by the effect of inductive transfer, due to simultaneous learning from all of the modeled endpoints. These results show that the field of protein descriptor research needs further improvements to truly realize the expected benefit of EL.
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