IN SILICO ANALYSIS OF NOVEL COMPOUNDS TARGETING THE SARS-COV-2 PAPAIN-LIKE PROTEASE
DOI:
https://doi.org/10.22159/ijap.2026v18i3.57936Keywords:
Papain-like protease (PLpro) inhibitors, Molecular docking, MM-GBSA, ADME, SARS-CoV-2, Drug discoveryAbstract
Objective: The present study aimed to design and computationally evaluate pyrimidine-based ring derivatives as potential inhibitors of SARS-CoV-2 papain-like protease (PLpro).
Methods: To find the binding affinity between designed compounds and papain-like protease (PLpro) was used molecular docking. Binding free energy and complex stability were verified using molecular mechanics–generalized born surface area (MM-GBSA) simulations. Additionally, the QikProp tool was used to estimate the absorption, distribution, metabolism, and excretion (ADME) characteristics of substances.
Results: Docking analysis showed that compound 2 had a glide score of -5.31 kcal/mol, comparable to the co-crystal (-2.10 kcal/mol). Key interactions with Ile548, Ser549, Ala550, Arg836, Asp833 and Ser814 contributed to its stability. Binding free energy analysis revealed that compound 2 (-74.24 kcal/mol).
Conclusion: Compound 2 demonstrated potential interactions with papain-like protease (PLpro), comparable to the co-crystal. These findings suggest that compound 2 is a promising lead candidate for SARS-CoV-2 (PLpro)-targeted therapy, warranting further preclinical and biological validation
References
1. To KKW, Sridhar S, Chiu KHY, Hung DLL, Li X, Hung IFN, Tam AR, Chung TWH, Chan JFW, Zhang AJX, Cheng VCC, Yuen KY. Lessons learned 1 year after SARS-CoV-2 emergence leading to COVID-19 pandemic. Emerging Microbes & Infections. 2021 Jan;10(1):507–35. DOI: https://doi.org/10.1080/22221751.2021.1898291
2. Chauhan S. Comprehensive review of coronavirus disease 2019 (COVID-19). Biomedical journal. 2020;43(4):334–40. DOI:https://doi.org/10.1016/j.bj.2020.05.023
3. Gorkhali R, Koirala P, Rijal S, Mainali A, Baral A, Bhattarai HK. Structure and Function of Major SARS-CoV-2 and SARS-CoV Proteins. BioinformBiol Insights. 2021 Jan;15:11779322211025876. DOI:https://doi.org/10.1177/11779322211025876
4. Zhang Q, Jia Q, Gao W, Zhang W. The role of deubiquitinases in virus replication and host innate immune response. Frontiers in Microbiology. 2022;13:839624. DOI:https://doi.org/10.3389/fmicb.2022.839624
5. Lai C, Chen W, Qin Y, Xu D, Lai Y, He S. Innovative Hydrogel Design: Tailoring Immunomodulation for Optimal Chronic Wound Recovery. Advanced Science. 2025 Jan;12(2):2412360.DOI: https://doi.org/10.1002/advs.202412360
6. Yin W, Luan X, Li Z, Zhou Z, Wang Q, Gao M, Wang X, Zhou F, Shi J, You E. Structural basis for inhibition of the SARS-CoV-2 RNA polymerase by suramin. Nature structural & molecular biology. 2021;28(3):319–25. DOI: https://doi.org/10.1038/s41594-021-00570-0
7. Suryawanshi SS, Jayannache PB, Patil RS, Ms P, Sg A. Molecular docking studies on screening and assessment of selected bioflavonoids as potential inhibitors of COVID-19 main protease. Asian J Pharm Clin Res. 2020;13(9):174–8. DOI: https://doi.org/10.22159/ajpcr.2020.v13i9.38485
8. Ibrahim TM, Ismail MI, Bauer MR, Bekhit AA, Boeckler FM. Supporting SARS-CoV-2 papain-like protease drug discovery: in silico methods and benchmarking. Frontiers in chemistry. 2020;8:592289.DOI: https://doi.org/10.3389/fchem.2020.592289
9. Indhumathi s, nithi ss, gobiananth mab, venkatheshan n, meena g, jayanthi k. Design and in silico evaluation of phenoxy acetamide derivatives as potential antidiabetic agents. Int J App Pharm. 2025;17(5):159–67. DOI: https://dx.doi.org/10.22159/ijap.2025v17i5.54892
10. Imam SS, Imam ST, Mdwasifathar K, Ammar MY. Interaction Between Ace 2 and SARS-CoV-2, And Use of EgcgAndTheaflavin to Treat Covid 19 in Initial Phases. Int J Curr Pharm Res. 2022;14:5–10. DOI:https://dx.doi.org/10.22159/ijcpr.2022v14i2.1945
11. Badavath VN, Sinha BN, Jayaprakash V. Design, in-silico docking and predictive ADME properties of novel pyrazoline derivatives with selective human MAO inhibitory activity. Int J Pharm Pharm Sci. 2015;7:277–82.
12. Azam F, Eid EE, Almutairi A. Targeting SARS-CoV-2 main protease by teicoplanin: A mechanistic insight by docking, MM/GBSA and molecular dynamics simulation. Journal of Molecular Structure. 2021;1246:131124. DOI:https://doi.org/10.1016/j.molstruc.2021.131124
13. Sgobba M, Caporuscio F, Anighoro A, Portioli C, Rastelli G. Application of a post-docking procedure based on MM-PBSA and MM-GBSA on single and multiple protein conformations. European Journal of Medicinal Chemistry. 2012;58:431–40.DOI:https://doi.org/10.1016/j.ejmech.2012.10.024.
14. Parveen S, Khalil R, Shafiq N, Rashid M, Nazli Z i H, Dawoud TM, Metouekel A, Bourhia M, Younous YA, Moveed A. Therapeutic switching of metronidazole anti-cancerous compounds as anti SARS-COV-2 inhibitors: integration of QSAR, molecular docking, MD simulation and ADMET analysis. Discov Life. 2024 Aug 9;54(1):10.DOI:https://doi.org/10.1007/s11084-024-09653-6
15. Dash S, Rathi E, Kumar A, Chawla K, Kini SG. Identification of DprE1 inhibitors for tuberculosis through integrated in-silico approaches. Scientific Reports. 2024;14(1):11315. DOI:https://doi.org/10.1038/s41598-024-61901-x
16. Wu C, Liu Y, Yang Y, Zhang P, Zhong W, Wang Y, Wang Q, Xu Y, Li M, Li X. Analysis of therapeutic targets for SARS-CoV-2 and discovery of potential drugs by computational methods. Acta Pharmaceutica Sinica B. 2020;10(5):766–88. DOI: https://doi.org/10.1016/j.apsb.2020.02.008
17. Swargiary A, Mahmud S, Saleh MdA. Screening of phytochemicals as potent inhibitor of 3-chymotrypsin and papain-like proteases of SARS-CoV2: an in silico approach to combat COVID-19. Journal of Biomolecular Structure and Dynamics. 2022 Mar 24;40(5):2067–81.DOI: https://doi.org/10.1080/07391102.2020.1835729
18. Valdés-Albuernes JL, Díaz-Pico E, Alfaro S, Caballero J. Modeling of noncovalent inhibitors of the papain-like protease (PLpro) from SARS-CoV-2 considering the protein flexibility by using molecular dynamics and cross-docking. Frontiers in Molecular Biosciences. 2024;11:1374364.DOI: https://doi.org/10.3389/fmolb.2024.1374364
19. Varghese A, Liu J, Liu B, Guo W, Dong F, Patterson TA, Hong H. Analysis of Structures of SARS-CoV-2 Papain-like Protease Bound with Ligands Unveils Structural Features for Inhibiting the Enzyme. Molecules. 2025;30(3):491. DOI: https://doi.org/10.3390/molecules30030491
20. Pendyala B, Patras A, Dash C. Phycobilins as potent food bioactive broad-spectrum inhibitors against proteases of SARS-CoV-2 and other coronaviruses: A preliminary study. Frontiers in Microbiology. 2021;12:645713. DOI:https://doi.org/10.3389/fmicb.2021.645713
21. Ratia K, Pegan S, Takayama J, Sleeman K, Coughlin M, Baliji S, Chaudhuri R, Fu W, Prabhakar BS, Johnson ME, Baker SC, Ghosh AK, Mesecar AD. A noncovalent class of papain-like protease/deubiquitinase inhibitors blocks SARS virus replication. Proc Natl Acad Sci USA. 2008 Oct 21;105(42):16119–24.DOI:https://doi.org/10.1073/pnas.0805240105.
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