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Kenno Vanommeslaeghe
LinkedIn Google Scholar
Analytical Chemistry, Applied Chemometrics |
Vrije Universiteit Brussel |
The Cystine/Glutamate Antiporter System xc⁻ (Sxc⁻) belongs to the SLC7 family of plasma membrane transporters and plays an important role in different parts of body, especially in central nervous system. Accordingly, its inhibition has been proposed as therapeutic strategy for several disease states such as cancer-induced bone pain and a number of neurological disorders, some of which are the subject of research led by A. Massie at the NAVI research group. Such research is hindered by a relative scarcity of specific inhibitors for Sxc⁻. Accordingly, the aim of this research project is to design novel selective Sxc⁻ modulators using target-based drug design strategies. A special challenge in this project is that, being a gradient-driven transporter, Sxc⁻ features a low binding affinity for its natural substrates. Consequently, searching for molecules that bind the protein in a similar way as its substrates is not expected to yield strong inhibitors. Instead, we aim to gain detailed knowledge of its transport pathway. This will not only be helpful in guiding our drug design project but also provide fundamental insights into the complex and interesting molecular mechanism of Sxc⁻ as a member of the SLC7 family.
In a first stage of this endeavor, we used a combination of multi-template homology modeling and explicit solvent Molecular Dynamics to obtain four distinct conformations of Sxc⁻.35 A first Virtual Screening round was performed against the inward-open conformation and the resulting 11 compounds were subjected to an in vitro assay in the Neuropharmacology group at the UCLouvain, led by E. Hermans. Follow-up Enhanced Sampling calculations are ongoing using a newly developed method.
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Activation of the serotonin 2A receptor (5-HT2AR) is associated with antidepressant effects but also hallucinations. There have long been indications that not all activating ligands trigger these effects to the same extent, indicating functional selectivity. More recently, it has been suggested that differential effects of 5-HT2AR ligands are a result of biased agonism (rather than differential binding profiles for related 5-HT receptor subtypes).
While the 5-HT2AR is a G protein coupled receptor (GPCR) and presumably shares its general activation mechanism with other members of this large and well-studied family, it is unclear how it would undergo biased agonism at a molecular level. We aim to contribute to answering this question39 using explicit solvent Molecular Dynamics as well as our newly developed Enhanced Sampling method. Once an "antidepressant-biased" conformation of the receptor is identified, ligands that specifically stabilize this conformation could be identified using virtual screening with the final goal to develop novel antidepressant pharmaceuticals that target 5-HT2AR without triggering hallucinogenic side-effects.
TopNovel compounds that modulate the transrepression pathway with sufficient selectivity to be of use in the search for therapies for stress-related mental disorders, in collaboration with D. De Bundel at the EFAR research group. In order to achieve this, molecules may need to interact with other parts of the receptor than the traditional corticoid binding pocket.
Ways to chemically trigger the transactivation pathway without transrepression. Compounds that have this particular effect do not exist yet, but could be used to modulate the proliferation of beta cells, which is the subject of research by K. Hellemans at the DIAB (Diabetes) Research Center.
High-Pressure Liquid Chromatography (HPLC) with chiral columns is a rare generally applicable technique for the separation of enantiomers, which is of high and increasing importance in drug discovery, production and analysis. For this reason, it forms a prominent line of research in our FABI research group. Computer models for predicting chiral separations are largely confined to a narrow chemical space defined by their training set.33 In our opinion, the main reasons for this are (1) a relatively limited computational tool chest for characterizing chiral properties of analytes and (2) incomplete insight into the molecular mechanism for the enantioselectivity of common stationary phases such as derivatized amylose and cellulose. The latter point represents a relative lack of fundamental knowledge, which we aim to address by studying the molecular mechanisms of chiral separation on these stationary phases with Molecular Dynamics simulation techniques.41 This study leverages our previously established expertise in force fields for carbohydrates and small organic molecules as well as advanced methods for trajectory analysis. In parallel, we seek to address point (1) above by developing new chiral molecular descriptors that are more strongly anchored in physical properties than the presently available chiral descriptors. A small-scale descriptor development pilot project has been conducted36 and the results of a more elaborate effort will be available soon.40
In agreement with the research goals outlined above, we set out to map the present field in nonbonded potentials. During this search, an opportunity presented itself to contribute to the state of the art by developing our own potential for van der Waals interactions. In a recently published paper in this subject,37 we demonstrate a near-quantitative agreement with high-level QM interaction energies of noble gas homo- and heterodimers. In addition, the work has interesting conceptual implications. Applying the model to molecular systems will be the subject of future work.
Automated methods for force field parametrization have attracted renewed interest of the community, but the robustness issues associated with the often ill-conditioned nature of parameter optimization have been vastly underappreciated in the recent literature. We developed a Linear Least Squares (LLS) procedure that is able to simultaneously fit all the bonded parameters in a Class I force field and includes a novel restraining strategy that overcomes robustness issues in the LLS fitting of bonded parameters while minimally impacting the fitted values of well-behaved parameters.26 The same procedure was also used for the fitting of the bond-charge increments in the next release of the CGenFF program, illustrating the method's potential for robustly solving general LLS problems beyond force field parametrization. The fitting part of the methodology was implemented in a C program named "lsfitpar" is available to the community under the Affero GPL. It hoped it will become an important part of the sprawling ecosystem of automatic parametrization interfaces. Future directions include further automation, validation of the methodology for the purpose of charge fitting, testing of its ability to use Monte Carlo conformational sampling data and extending the program's feature set.
In its most basic form, Adaptive Biasing Force (ABF) enhances conformational sampling along a small number of predefined (transition) coordinates while determining the corresponding Potential of Mean Force. Unfortunately, the convergence rate of basic ABF on biomolecules is not always optimal. Multiple strategies and ABF variants have been developed to combat this problem. However, their effective use largely negates the upfront simplicity of the ABF method, requiring pre-existing knowledge of the system as well as some fundamental insight in free energy methods. In the present project, we demonstrated how a previously underappreciated hysteresis mechanism causes basic ABF simulations to fail catastrophically on two real-life biomolecular test cases. We subsequently developed a new ABF variant that effectively addresses this issue without introducing additional parameters or complexity, thereby retaining the simplicity and ease-of-use of basic ABF. We anticipate that the resulting method will be appealing for use by inexperienced operators as well as for the purpose of automating certain types of free energy calculations. A manuscript about this work is in preparation (which is why so few details are given on this website 😜).
Empirical force fields20 are presently the only computational methods fast enough to routinely perform molecular dynamics simulations of large chemical systems, such as proteins, on relevant time scales. The CHARMM force field is widely used for simulating biomolecular systems, being capable of representing proteins, nucleic acids, lipids and carbohydrates.22 The CHARMM General Force Field (CGenFF) adds to this a wide range of chemical groups present in biomolecules and drug-like molecules including a large number of heterocyclic scaffolds. CGenFF thus makes it possible to perform "all-CHARM" simulations on drug-target interactions thereby extending the utility of CHARMM force fields to medicinally relevant systems. As a validation, CGenFF was shown to accurately reproduce geometric, vibrational and energetic data, including interactions with water, as well as satisfactorily reproducing the experimental molecular volumes for 111 pure solvents and heats of vaporization of 95 molecules.9![]() |
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My CGenFF page (mainly links to current and archived CGenFF resources)
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My first contact with peptidomimetics mimicking specific secondary structure motifs was in the Dirk Tourwé lab, where this was a major research topic, and where I assisted in conformational studies aimed at determining the β-turn propensity of 4-Amino-1,2,4,5-tetrahydro-2-benzazepin-3-ones and derivatives.5 Several years later, when working in the MacKerell lab, I became involved in Steven Fletcher's research on α-helix and β-sheet mimetics. In this context, I assisted in the design of oligoamide-foldamer-based α-helix mimetics that target the interaction of the BCL-xL oncoprotein with the pro-apoptotic BAK protein,13,18 as well as the design of a 1,2-diphenylacetylene-based scaffold for amphipathic α-helix mimetics with potential applications in binding the Mcl-1 oncoprotein.19 Work on a β-sheet mimetic with therapeutic potential against cancer through a different mechanism is also in progress.
This project is a collaborative effort involving the Molecular Biology group of Ari Melnick, the X-ray Crystallography and Structural Biology group of Gil Privé, the Organic Chemistry group of Andrew Coop and Alex MacKerell's CADD center. The aim of this collaboration is to develop novel anti-cancer drugs that target the BCL6 oncogenic transcriptional repressor. As part of Alex MacKerell's group, my role consisted mainly of assisting in the discovery of new leads by means of in silico screening of libraries of commercially available compounds. In this context, I employed both ligand-based and structure-based drug design strategies. In other words, I identified new leads by their chemical homology to known inhibitors as well as their binding affinity to relevant parts of BCL6, as predicted by docking studies.30
41. F. Ameli, R. Van de Velde, Y. Vander Heyden, D. Mangelings, K. Vanommeslaeghe, manuscript in preparation.
40. J. Peeters, P. De Gauquier, F. Ameli, Y. Vander Heyden, D. Mangelings, K. Vanommeslaeghe, submitted.
39. J. Peeters, D. De Bundel, K. Vanommeslaeghe, Molecular dynamics study of differential effects of serotonin-2A-receptor (5-HT2AR) modulators, PLOS Comput. Biol. 2025, 21(9): e1013000. DOI: 10.1371/journal.pcbi.1013000 .
38. K. Vanommeslaeghe, Collagen as a stress test and a tool for improvement of glycine and proline conformations in biomolecular force fields, Biophys. J. 2025, 124, 2566-2568. DOI: 10.1016/j.bpj.2025.07.018 .
37. J. Peeters, K. Vanommeslaeghe, A simple model for the Pauli Repulsion with possible utility in QM, MM and Chemical Education, J. Chem. Theory Comput. 2024, 20, 6728-6737. DOI: 10.1021/acs.jctc.4c00748 .
36. P. De Gauquier, J. Peeters, K. Vanommeslaeghe, Y. Vander Heyden, D. Mangelings, Modelling the enantiorecognition of structurally diverse pharmaceuticals on O-substituted polysaccharide-based stationary phases, Talanta 2023, 259, 124497. DOI: 10.1016/j.talanta.2023.124497 .
35. T. D. Hang, H. M. Hung, P. Beckers, N. Desmet, M. Lamrani, A. Massie, E. Hermans, K. Vanommeslaeghe, Structural investigation of human cystine/glutamate antiporter System xc⁻ (Sxc⁻) using homology modeling and molecular dynamics, Front. Mol. Biosci. 2022, 126:1064199. DOI: 10.3389/fmolb.2022.1064199 .
34. C. Jeong, R. Franklin, K. J. Edler, K. Vanommeslaeghe, S. Krueger, J. E. Curtis, Styrene-Maleic Acid Copolymer Nanodiscs to Determine the Shape of Membrane Proteins, J. Phys. Chem. B 2022, 126, 1034-1044. DOI: 10.1021/acs.jpcb.1c05050 .
33. P. De Gauquier, K. Vanommeslaeghe, Y. Vander Heyden, D. Mangelings, Modelling approaches for chiral chromatography on polysaccharide-based and macrocyclic antibiotic chiral selectors: A review, Anal. Chim. Acta 2022, 1198, 338861. DOI: 10.1016/j.aca.2021.338861 .
32. L. A. Burns, J. C. Faver, Z. Zheng, M. S. Marshall, D. G. A. Smith, K. Vanommeslaeghe, A. D. MacKerell Jr., K. M. Merz, and C. D. Sherrill, The BioFragment Database (BFDb): An open-data platform for computational chemistry analysis of noncovalent interactions, J. Chem. Phys. 2017, 147:161727. DOI: 10.1063/1.5001028 .
31. I. S. Gutiérrez, F.-Y. Lin, K. Vanommeslaeghe, J. A. Lemkul, K. A. Armacost, C. L. Brooks III, A. D. MacKerell Jr., Parametrization of halogen bonds in the CHARMM general force field: Improved treatment of ligand-protein interactions, Bioorg. Med. Chem. 2016, 24, 4812-4825. DOI: 10.1016/j.bmc.2016.06.034 .
30. M. G. Cardenas, W. Yu, W. Beguelin, M. R. Teater, H. Geng, R. L. Goldstein, E. Oswald, K. Hatzi, S.-N. Yang, J. Cohen, R. Shaknovich, K. Vanommeslaeghe, H. Cheng, D. Liang, H. J. Cho, J. Abbott, W. Tam, W. Du, J. P. Leonard, O. Elemento, L. Cerchietti, T. Cierpicki, F. Xue, A. D. MacKerell Jr., A. M. Melnick, Rationally designed BCL6 inhibitors target activated B cell diffuse large B cell lymphoma, J. Clin. Invest. 2016, 126, 3351-3362. DOI: 10.1172/JCI85795 .
29. Y. Xu, K. Vanommeslaeghe, A. Aleksandrov, A. D. MacKerell Jr., L. Nilsson, Additive CHARMM Force Field for Naturally Occurring Modified Ribonucleotides, J. Comput. Chem. 2016, 37, 896-912. DOI: 10.1002/jcc.24307 .
28. C. Domene, C. Jorgensen, K. Vanommeslaeghe, C. J. Schofield, A. D. MacKerell Jr., Quantifying the binding interaction between the hypoxia-inducible transcription factor and the von Hippel Lindau suppressor, J. Chem. Theory Comput. 2015, 11, 3946-3954. DOI: 10.1021/acs.jctc.5b00411 .
27. C. Jorgensen, L. Darre, K. Vanommeslaeghe, K. Omoto, D. Pryde, C. Domene, In-silico identification of PAP-1 binding sites in the Kv1.2 potassium channel, Mol. Pharmaceutics 2015, 12, 1299-1307. DOI: 10.1021/acs.molpharmaceut.5b00023 .
26. K. Vanommeslaeghe, M. Yang, A. D. MacKerell Jr., Robustness in the fitting of Molecular Mechanics parameters, J. Comput. Chem. 2015, 36, 1083-1101. DOI: 10.1002/jcc.23897 .
25. S. Jo, X. Cheng, S. M. Islam, L. Huang, H. Rui, A. Zhu, H. S. Lee, Y. Qi, W. Han, K. Vanommeslaeghe, A. D. MacKerell Jr., Benoît Roux, W. Im, CHARMM-GUI PDB Manipulator for Advanced Modeling and Simulations of Proteins Containing Nonstandard Residues, Adv. Protein Chem. Struct. Biol. 2014, 96, 235-265. DOI: 10.1016/bs.apcsb.2014.06.002 .
24. N. R. Kern, H. S. Lee, E. L. Wu, S. Park, K. Vanommeslaeghe, A. D. MacKerell Jr., J. B. Klauda, S. Jo, W. Im, Lipid-Linked Oligosaccharides in Membranes Sample Conformations that Facilitate Binding to Oligosaccharyltransferase, Biophys. J. 2014, 107, 1885-1895. DOI: 10.1016/j.bpj.2014.09.007 .
23. S. S. Mallajosyula, K. Vanommeslaeghe, A. D. MacKerell Jr., Perturbation of Long-Range Water Dynamics as the Mechanism for the Antifreeze Activity of Antifreeze Glycoprotein, J. Phys. Chem. B 2014, 118, 11696-11706. DOI: 10.1021/jp508128d .
22. K. Vanommeslaeghe, A. D. MacKerell Jr., CHARMM additive and polarizable force fields for biophysics and computer-aided drug design, Biochim. Biophys. Acta 2015, 1850, 861-871. DOI: 10.1016/j.bbagen.2014.08.004 .
21. P. Kumar, S. A. Bojarowski, K. N. Jarzembska, S. Domagała, K. Vanommeslaeghe, A. D. MacKerell Jr., P. M. Dominiak, A Comparative Study of Transferable Aspherical Pseudoatom Databank and Classical Force Fields for Predicting Electrostatic Interactions in Molecular Dimers, J. Chem. Theory Comput. 2014, 10, 1652-1664. DOI: 10.1021/ct4011129 .
20. K. Vanommeslaeghe, O. Guvench, A. D. MacKerell Jr., Molecular Mechanics, Curr. Pharm. Des. 2014, 20, 3281-3292. DOI: 10.2174/13816128113199990600 .
19. K.-Y. Jung, K. Vanommeslaeghe, M. E. Lanning, J. L. Yap, C. Gordon, P. T. Wilder, A. D. MacKerell Jr., S. Fletcher, Amphipathic α-helix mimetics based on a 1,2-diphenylacetylene scaffold, Org. Lett. 2013, 15, 3234-3237. DOI: 10.1021/ol401197n .
18. X. Cao, J. L. Yap, M. K. Newell-Rogers, C. Peddaboina, W. Jiang, H. T. Papaconstantinou, D. Jupitor, A. Rai, K.-Y. Jung, R. P. Tubin, W. Yu, K. Vanommeslaeghe, P. T. Wilder, A. D. MacKerell Jr., S. Fletcher, R. W. Smythe, The novel BH3 alpha-helix mimetic JY-1-106 induces apoptosis in a subset of cancer cells (lung cancer, colon cancer and mesothelioma) by disrupting Bcl-xL and Mcl-1 protein-protein interactions with Bak, Mol. Cancer 2013, 12:42. DOI: 10.1186/1476-4598-12-42 .
17. K. Vanommeslaeghe, E. P. Raman, A. D. MacKerell Jr., Automation of the CHARMM General Force Field (CGenFF) II: Assignment of bonded parameters and partial atomic charges, J. Chem. Inf. Model. 2012, 52, 3155-3168. DOI: 10.1021/ci3003649 .
16. K. Vanommeslaeghe, A. D. MacKerell Jr., Automation of the CHARMM General Force Field (CGenFF) I: bond perception and atom typing, J. Chem. Inf. Model. 2012, 52, 3144-3154. DOI: 10.1021/ci300363c .
15. W. Yu, X. He, K. Vanommeslaeghe, A. D. MacKerell Jr., Extension of the CHARMM General Force Field to Sulfonyl-Containing Compounds and Its Utility in Biomolecular Simulations, J. Comput. Chem. 2012, 33, 2451-2468. DOI: 10.1002/jcc.23067 .
14. E. P. Raman, K. Vanommeslaeghe, A. D. MacKerell Jr., Site-Specific Fragment Identification Guided by Single-Step Free Energy Perturbation Calculations, J. Chem. Theory Comput. 2012, 8, 3513-3525. DOI: 10.1021/ct300088r .
13. J. L. Yap, X. B. Cao, K. Vanommeslaeghe, K. Y. Jung, C. Peddaboina, P. T. Wilder, A. Nan, A. D. MacKerell Jr., W. R. Smythe, S. Fletcher, Relaxation of the rigid backbone of an oligoamide-foldamer-based α-helix mimetic: identification of potent Bcl-xL inhibitors, Org. Biomol. Chem. 2012, 10, 2928-2933. DOI: 10.1039/c2ob07125h .
12. A. Krishtal, D. Geldof, K. Vanommeslaeghe, C. Van Alsenoy, P. Geerlings, Evaluating London Dispersion Interactions in DFT: A Nonlocal Anisotropic Buckingham-Hirshfeld Model, J. Chem. Theory Comput. 2012, 8, 125-134. DOI: 10.1021/ct200718y .
11. O. Guvench, S. S. Mallajosyula, E. P. Raman, E. Hatcher, K. Vanommeslaeghe, T. J. Foster, F. W. Jamison, A. D. MacKerell Jr., CHARMM Additive All-Atom Force Field for Carbohydrate Derivatives and Its Utility in Polysaccharide and Carbohydrate-Protein Modeling, J. Chem. Theory Comput. 2011, 7, 3162-3180. DOI: 10.1021/ct200328p .
10. A. Krishtal, K. Vanommeslaeghe, D. Geldof, C. Van Alsenoy, P. Geerlings, Importance of anisotropy in the evaluation of dispersion interactions, Phys. Rev. A 2011, 83:024501. DOI: 10.1103/PhysRevA.83.024501 .
9. K. Vanommeslaeghe, E. Hatcher, C. Acharya, S. Kundu, S. Zhong, J. Shim, E. Darian, O. Guvench, P. Lopes, I. Vorobyov, A. D. MacKerell Jr., CHARMM General Force Field (CGenFF): A force field for drug-like molecules compatible with the CHARMM all-atom additive biological force fields, J. Comput. Chem. 2010, 31, 671-690. DOI: 10.1002/jcc.21367 .
8. A. Krishtal, K. Vanommeslaeghe, A. Olasz, T. Veszprémi, C. Van Alsenoy, P. Geerlings, Accurate interaction energies at DFT level by means of an efficient dispersion correction, J. Chem. Phys. 2009, 130:174101. DOI: 10.1063/1.3126248 .
7. A. Olasz, K. Vanommeslaeghe, A. Krishtal, T. Veszprémi, C. Van Alsenoy, P. Geerlings, The use of atomic intrinsic polarizabilities in the evaluation of the dispersion energy, J. Chem. Phys. 2007, 127:224105. DOI: 10.1063/1.2805391 .
6. K. Vanommeslaeghe, P. Mignon, S. Loverix, D. Tourwé P. Geerlings, Influence of stacking on the hydrogen bond donating capacity of nucleic bases, J. Chem. Theory Comput. 2006, 2, 1444-1452. DOI: 10.1021/ct600150n .
5. K. Van Rompaey, S. Ballet, C. Tömböly, R. De Wachter, K. Vanommeslaeghe, M. Biesemans, R. Willem, D. Tourwé, Synthesis and evaluation of the β-turn properties of 4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-ones and of their spirocyclic derivative, Eur. J. Org. Chem. 2006, 2899-2911. DOI: 10.1002/ejoc.200500996 .
4. K. Vanommeslaeghe, S. Loverix, P. Geerlings, D. Tourwé, DFT-based Ranking of Zinc-chelating Groups in Histone Deacetylase Inhibitors, Bioorg. Med. Chem. 2005, 13, 6070-6082. DOI: 10.1016/j.bmc.2005.06.009 .
3. K. Vanommeslaeghe, F. De Proft, S. Loverix, D. Tourwé, P. Geerlings, Theoretical study revealing the functioning of a novel combination of catalytic motives in Histone Deacetylase, Bioorg. Med. Chem. 2005, 13, 3987-3992. DOI: 10.1016/j.bmc.2005.04.001 .
2. K. Vanommeslaeghe, C. Van Alsenoy, F. De Proft, J. C. Martins, D. Tourwé, P. Geerlings, Ab Initio study of the binding of Trichostatin A (TSA) in the active site of Histone Deacetylase Like Protein (HDLP), Org. Biomol. Chem. 2003, 1, 2951-2957. DOI: 10.1039/b304707e .
1. K. Vanommeslaeghe, G. Elaut, V. Brecx, P. Papeleu, K. Iterbeke, P. Geerlings, D. Tourwé, V. Rogiers, Amide analogues of TSA: synthesis, binding mode analysis and HDAC inhibition, Bioorg. Med. Chem. Lett. 2003, 13, 1861-1864. DOI: 10.1016/S0960-894X(03)00284-1 .