Talaromyces marneffei is a dimorphic fungal pathogen that survives within host macrophages by counteracting oxidative and immune stress. Recently, several host macrophage proteins interacting with the antigenic T. marneffei glutathione peroxidase TmGpx1 were identified. Among these candidate proteins, the regulatory subunit of casein kinase 2, CK2β (CSNK2B), was selected for structural modeling and molecular dynamics simulations to investigate the molecular basis of the host-pathogen interaction. Our findings also suggest a previously unrecognized role for fungal glutathione peroxidase in modulating host cytoskeleton regulation. Here, we used an AlphaFold3-based structure prediction and molecular dynamics simulations to characterize and evaluate the TmGpx1–CK2β interaction. The complex remained stably associated throughout the 200 ns simulations, with sustained intermolecular proximity, extensive heavy-atom contacts, and a persistent hydrogen-bond network. MM/GBSA calculations indicated a favorable total binding energy (−58.17 ± 13.13 kcal/mol), driven mainly by van der Waals and electrostatic contributions. Two contact pairs, TmGpx1 Arg128–CK2β Trp12 and TmGpx1 Val126–CK2β Glu73, were conserved across all three replicates and coincided with the residues contributing most favorably to binding energy. Notably, TmGpx1 Leu123, Leu124, and Val126—residues previously implicated in the TmGpx1–FKBP15 interaction—recurred at the CK2β interface, and the TmGpx1 catalytic triad (Cys39, Gln76, Trp131) was also engaged in CK2β binding. These findings support a stable and energetically favorable TmGpx1–CK2β interface and suggest that TmGpx1 recognizes multiple host regulatory proteins through a shared interaction surface that may be functionally linked to its catalytic activity.
- Open Access
- Article
Structural and Energetic Characterization of the TmGpx1–CK2β Complex Using Molecular Dynamics Simulations
Author Information
Received: 01 August 2026 | Revised: 20 August 2026 | Accepted: 08 October 2026 | Published: 19 October 2026
Abstract
Keywords
Talaromyces marneffei | TmGpx1 | glutathione peroxidase | CK2β (CSNK2B) | molecular dynamics simulation | protein–protein interaction | moonlighting protein | host–pathogen interaction
References
- 1.
Pruksaphon, K.; Nosanchuk, J.D.; Ratanabanangkoon, K.; et al. Talaromyces Marneffei Infection: Virulence, Intracellular Lifestyle and Host Defense Mechanisms. J. Fungi 2022, 8, 200. https://doi.org/10.3390/jof8020200.
- 2.
Narayanasamy, S.; Dougherty, J.; van Doorn, H.R.; et al. Pulmonary Talaromycosis: A Window into the Immunopathogenesis of an Endemic Mycosis. Mycopathologia 2021, 186, 707–715. https://doi.org/10.1007/s11046-021-00570-0.
- 3.
Pasricha, S.; MacRae, J.I.; Chua, H.H.; et al. Extensive Metabolic Remodeling Differentiates Non-Pathogenic and Pathogenic Growth Forms of the Dimorphic Pathogen Talaromyces Marneffei. Front. Cell. Infect. Microbiol. 2017, 7, 368. https://doi.org/10.3389/fcimb.2017.00368.
- 4.
Cogliati, M.; Roverselli, A.; Boelaert, J.R.; et al. Development of an in Vitro Macrophage System to Assess Penicillium Marneffei Growth and Susceptibility to Nitric Oxide. Infect. Immun. 1997, 65, 279–284. https://doi.org/10.1128/iai.65.1.279-284.1997.
- 5.
Pongpom, M.; Vanittanakom, P.; Nimmanee, P.; et al. Adaptation to Macrophage Killing by Talaromyces marneffei. Future Sci. OA 2017, 3, FSO215. https://doi.org/10.4155/fsoa-2017-0032.
- 6.
Ellett, F.; Pazhakh, V.; Pase, L.; et al. Macrophages Protect Talaromyces Marneffei Conidia from Myeloperoxidase-Dependent Neutrophil Fungicidal Activity during Infection Establishment in Vivo. PLOS Pathog. 2018, 14, e1007063. https://doi.org/10.1371/journal.ppat.1007063.
- 7.
Tiwari, S.; Thakur, R.; Shankar, J. Role of Heat-Shock Proteins in Cellular Function and in the Biology of Fungi. Biotechnol. Res. Int. 2015, 2015, 132635. https://doi.org/10.1155/2015/132635.
- 8.
Payne, M.; Weerasinghe, H.; Tedja, I.; et al. A Unique Aspartyl Protease Gene Expansion in Talaromyces marneffei Plays a Role in Growth inside Host Phagocytes. Virulence 2019, 10, 277–291. https://doi.org/10.1080/21505594.2019.1593776.
- 9.
Wangsanut, T.; Amsri, A.; Pongpom, M. Antibody Screening Reveals Antigenic Proteins Involved in Talaromyces Marneffei and Human Interaction. Front. Cell. Infect. Microbiol. 2023, 13, 1118979. https://doi.org/10.3389/fcimb.2023.1118979.
- 10.
Pongpom, M.; Vanittanakom, N. Stress Adaptation in Talaromyces Marneffei. Chiang Mai Med. J. 2016, 55, 23–30. https://doi.org/10.14456/cmmj.2016.3.
- 11.
Yang, B.; Wang, J.; Jiang, H.; et al. Extracellular Vesicles Derived from Talaromyces Marneffei Yeasts Mediate Inflammatory Response in Macrophage Cells by Bioactive Protein Components. Front. Microbiol. 2021, 11, 603183. https://doi.org/10.3389/fmicb.2020.603183.
- 12.
Coschigano, P.W.; Magasanik, B. The URE2 Gene Product of Saccharomyces cerevisiae Plays an Important Role in the Cellular Response to the Nitrogen Source and Has Homology to Glutathione S-Transferases. Mol. Cell. Biol. 1991, 11, 822–832. https://doi.org/10.1128/mcb.11.2.822-832.1991.
- 13.
Karkowska-Kuleta, J.; Kozik, A. Moonlighting Proteins as Virulence Factors of Pathogenic Fungi, Parasitic Protozoa and Multicellular Parasites. Mol. Oral Microbiol. 2014, 29, 270–283. https://doi.org/10.1111/omi.12078.
- 14.
Wangsanut, T.; Aung, Y.H.H.; Oo, Y.H.H.; et al. Glutathione Peroxidase from Talaromyces Marneffei Interacts with Host Cytoskeletal Proteins: Insights from Yeast Two-Hybrid and Molecular Dynamics Simulations. Int. J. Mol. Sci. 2026, 27, 4259. https://doi.org/10.3390/ijms27104259.
- 15.
Litchfield, D.W. Protein Kinase CK2: Structure, Regulation and Role in Cellular Decisions of Life and Death. Biochem. J. 2003, 369, 1–15. https://doi.org/10.1042/bj20021469.
- 16.
Chantalat, L.; Leroy, D.; Filhol, O.; et al. Crystallization and Preliminary X-Ray Diffraction Analysis of the Regulatory Subunit of Human Protein Kinase CK2. Acta Crystallogr. Sect. D Biol. Crystallogr. 1999, 55, 895–897. https://doi.org/10.1107/s0907444998016680.
- 17.
Canton, D.A.; Litchfield, D.W. The Shape of Things to Come: An Emerging Role for Protein Kinase CK2 in the Regulation of Cell Morphology and the Cytoskeleton. Cell. Signal. 2006, 18, 267–275. https://doi.org/10.1016/j.cellsig.2005.07.008.
- 18.
D’Amore, C.; Salizzato, V.; Borgo, C.; et al. A Journey through the Cytoskeleton with Protein Kinase CK2. Curr. Protein Pept. Sci. 2019, 20, 547–562. https://doi.org/10.2174/1389203720666190119124846.
- 19.
Lim, A.C.B.; Tiu, S.Y.; Li, Q.; et al. Direct Regulation of Microtubule Dynamics by Protein Kinase CK2. J. Biol. Chem. 2004, 279, 4433–4439. https://doi.org/10.1074/jbc.m310563200.
- 20.
Münzer, P.; Walker-Allgaier, B.; Geue, S.; et al. CK2β Regulates Thrombopoiesis and Ca2+-Triggered Platelet Activation in Arterial Thrombosis. Blood 2017, 130, 2774–2785. https://doi.org/10.1182/blood-2017-05-784413.
- 21.
Larson, S.R.; Bortell, N.; Illies, A.; et al. Myeloid Cell CK2 Regulates Inflammation and Resistance to Bacterial Infection. Front. Immunol. 2020, 11, 590266. https://doi.org/10.3389/fimmu.2020.590266.
- 22.
Abramson, J.; Adler, J.; Dunger, J.; et al. Accurate Structure Prediction of Biomolecular Interactions with AlphaFold 3. Nature 2024, 630, 493–500. https://doi.org/10.1038/s41586-024-07487-w.
- 23.
Krokidis, M.G.; Koumadorakis, D.E.; Lazaros, K.; et al. AlphaFold3: An Overview of Applications and Performance Insights. Int. J. Mol. Sci. 2025, 26, 3671. https://doi.org/10.3390/ijms26083671.
- 24.
Lobanov, M.Y.; Bogatyreva, N.S.; Galzitskaya, O.V. Radius of Gyration as an Indicator of Protein Structure Compactness. Mol. Biol. 2008, 42, 623–628. https://doi.org/10.1134/s0026893308040195.
- 25.
Valdés-Tresanco, M.S.; Valdés-Tresanco, M.E.; Valiente, P.A.; et al. gmx_MMPBSA: A New Tool to Perform End-State Free Energy Calculations with GROMACS. J. Chem. Theory Comput. 2021, 17, 6281–6291. https://doi.org/10.1021/acs.jctc.1c00645.
- 26.
Sivachandran, N.; Cao, J.Y.; Frappier, L. Epstein-Barr Virus Nuclear Antigen 1 Hijacks the Host Kinase CK2 to Disrupt PML Nuclear Bodies. J. Virol. 2010, 84, 11113–11123. https://doi.org/10.1128/jvi.01183-10.
- 27.
Cao, J.Y.; Shire, K.; Landry, C.; et al. Identification of a Novel Protein Interaction Motif in the Regulatory Subunit of Casein Kinase 2. Mol. Cell. Biol. 2014, 34, 246–258. https://doi.org/10.1128/mcb.00968-13.
- 28.
Alvarez, D.E.; Agaisse, H. Casein Kinase 2 Regulates Vaccinia Virus Actin Tail Formation. Virology 2012, 423, 143–151. https://doi.org/10.1016/j.virol.2011.12.003.
- 29.
Montenarh, M.; Grässer, F.A.; Götz, C. Protein Kinase CK2 and Epstein–Barr Virus. Biomedicines 2023, 11, 358. https://doi.org/10.3390/biomedicines11020358.
- 30.
Bidoia, C.; Mazzorana, M.; Pagano, M.A.; et al. The Pleiotropic Protein Kinase CK2 Phosphorylates HTLV-1 Tax Protein in Vitro, Targeting Its PDZ-Binding Motif. Virus Genes 2010, 41, 149–157. https://doi.org/10.1007/s11262-010-0494-3.
- 31.
Bednarek, A.; Satala, D.; Zawrotniak, M.; et al. Glyceraldehyde 3-Phosphate Dehydrogenase on the Surface of Candida Albicans and Nakaseomyces Glabratus Cells—a Moonlighting Protein that Binds Human Vitronectin and Plasminogen and Can Adsorb to Pathogenic Fungal Cells via Major Adhesins Als3 and Epa6. Int. J. Mol. Sci. 2024, 25, 1013. https://doi.org/10.3390/ijms25021013.
- 32.
Urban, C.; Xiong, X.; Sohn, K.; et al. The Moonlighting Protein Tsa1p Is Implicated in Oxidative Stress Response and in Cell Wall Biogenesis in Candida albicans. Mol. Microbiol. 2005, 57, 1318–1341. https://doi.org/10.1111/j.1365-2958.2005.04771.x.
This work is licensed under a Creative Commons Attribution 4.0 International License.
