{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:40:21Z","timestamp":1785404421978,"version":"3.56.0"},"reference-count":35,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIH","award":["U19 AI171954-01"],"award-info":[{"award-number":["U19 AI171954-01"]}]},{"DOI":"10.13039\/100000060","name":"NIAID","doi-asserted-by":"crossref","award":["PHS398"],"award-info":[{"award-number":["PHS398"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Center for Diagnostics and Therapeutics\/Georgia State University"},{"DOI":"10.13039\/100008545","name":"Georgia State University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100008545","id-type":"DOI","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03qt6ba18","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Machupo virus (MACV) is the causal agent of Bolivian Hemorrhagic fever. It is highly pathogenic, has a high mortality rate, and currently lacks specific treatments or vaccines. MACV belongs to the Arenaviridae family, which uses a cap-snatching mechanism during the transcription process. Its viral polymerase, the L protein, harbors the endonuclease activity required for cap snatching, making it a suitable target for the development of antiviral therapeutics. We combined experimental and computational methods to characterize MACV endonuclease activity and evaluate inhibitors. A fluorescence resonance energy transfer (FRET) assay was used to measure the enzymatic activity of endonuclease and identify potent inhibitors via high-throughput screening. FRET assays identified BW-148, an inhibitor with a 48.4 \u00b5M (95% CI: 37.3\u201359.3 \u00b5M; R2 = 0.98) IC50, and a KD of 13.7 \u00b5M (95% CI: 8.2\u201319.2 \u00b5M, n = 3). Docking studies reveal that BW-148 may bind near the MACV endonuclease catalytic site, inhibiting enzymatic activities by metal chelating. BW-148 is a useful lead compound for further optimization of Machupo endonuclease inhibitors.<\/jats:p>","DOI":"10.3390\/microorganisms14061377","type":"journal-article","created":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T09:49:55Z","timestamp":1782121795000},"page":"1377","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Inhibitors of the Machupo Virus L Endonuclease for Bolivian Hemorrhagic Fever Treatments"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-9152-5497","authenticated-orcid":false,"given":"Oluwafoyinsola O.","family":"Faniyi","sequence":"first","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"},{"name":"Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0395-673X","authenticated-orcid":false,"given":"Kristin V.","family":"Lyles","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4608-3123","authenticated-orcid":false,"given":"Neva","family":"Agarwala","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haozhe","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Biology, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elise","family":"Copeland","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-1990-2113","authenticated-orcid":false,"given":"Teri","family":"Tran","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuyue","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1651-7488","authenticated-orcid":false,"given":"Bingchen","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"},{"name":"Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2200-5270","authenticated-orcid":false,"given":"Binghe","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"},{"name":"Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoxiao","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1766-3487","authenticated-orcid":false,"given":"Ming","family":"Luo","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Georgia State University, Atlanta, GA 30302, USA"},{"name":"Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, GA 30302, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1526","DOI":"10.3201\/eid1509.090017","article-title":"Reemergence of Bolivian hemorrhagic fever, 2007\u20132008","volume":"15","author":"Aguilar","year":"2009","journal-title":"Emerg. Infect. Dis."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e01741-19","DOI":"10.1128\/JVI.01741-19","article-title":"Monoclonal Antibodies with Neutralizing Activity and Fc-Effector Functions against the Machupo Virus Glycoprotein","volume":"94","author":"Amanat","year":"2020","journal-title":"J. Virol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1517\/17460441.2012.687719","article-title":"Drug discovery technologies and strategies for Machupo virus and other New World arenaviruses","volume":"7","author":"Radoshitzky","year":"2012","journal-title":"Expert Opin. Drug Discov."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.coviro.2014.02.007","article-title":"Epidemiology and pathogenesis of Bolivian hemorrhagic fever","volume":"5","author":"Patterson","year":"2014","journal-title":"Curr. Opin. Virol."},{"key":"ref_5","unstructured":"Public Health Agency of Canada (2026, May 14). Pathogen Safety Data Sheets: Infectious Substances\u2014Machupo Virus. Government of Canada 2026. Available online: https:\/\/www.canada.ca\/en\/public-health\/services\/laboratory-biosafety-biosecurity\/pathogen-safety-data-sheets-risk-assessment\/machupo-virus.html#note1."},{"key":"ref_6","unstructured":"MircrobeWiki (2026, May 14). Machupo Virus. MicrobeWiki. Available online: https:\/\/microbewiki.kenyon.edu\/index.php\/Machupo_virus."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1093\/clind\/24.4.718","article-title":"Treatment of Bolivian Hemorrhagic Fever with Intravenous Ribavirin","volume":"24","author":"Kilgore","year":"1997","journal-title":"Clin. Infect. Dis."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/j.ijid.2021.02.046","article-title":"South American Hemorrhagic Fevers: A summary for clinicians","volume":"105","author":"Frank","year":"2021","journal-title":"Int. J. Infect. Dis."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"8259","DOI":"10.1128\/JVI.00761-09","article-title":"Unusual molecular architecture of the machupo virus attachment glycoprotein","volume":"83","author":"Bowden","year":"2009","journal-title":"J. Virol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"109888","DOI":"10.1016\/j.virol.2023.109888","article-title":"Development of reverse genetic tools to study Chapare and Machupo viruses","volume":"588","author":"Jain","year":"2023","journal-title":"Virology"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e0020922","DOI":"10.1128\/jvi.00209-22","article-title":"Machupo Virus with Mutations in the Transmembrane Domain and Glycosylation Sites of the Glycoprotein Is Attenuated and Immunogenic in Animal Models of Bolivian Hemorrhagic Fever","volume":"96","author":"Mantlo","year":"2022","journal-title":"J. Virol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"615","DOI":"10.1038\/s41586-020-2114-2","article-title":"Structural insight into arenavirus replication machinery","volume":"579","author":"Peng","year":"2020","journal-title":"Nature"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Reguera, J., Gerlach, P., Rosenthal, M., Gaudon, S., Coscia, F., G\u00fcnther, S., and Cusack, S. (2016). Comparative Structural and Functional Analysis of Bunyavirus and Arenavirus Cap-Snatching Endonucleases. PLoS Pathog., 12.","DOI":"10.1371\/journal.ppat.1005636"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Rosenthal, M., Gogrefe, N., Vogel, D., Reguera, J., Rauschenberger, B., Cusack, S., G\u00fcnther, S., and Reindl, S. (2017). Structural insights into reptarenavirus cap-snatching machinery. PLoS Pathog., 13.","DOI":"10.1371\/journal.ppat.1006400"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1038\/s41579-020-00501-8","article-title":"Structural insights into RNA polymerases of negative-sense RNA viruses","volume":"19","author":"Grimes","year":"2021","journal-title":"Nat. Rev. Microbiol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Moianos, D., Prifti, G.M., Makri, M., and Zoidis, G. (2023). Targeting Metalloenzymes: The \u201cAchilles\u2019 Heel\u201d of Viruses and Parasites. Pharmaceuticals, 16.","DOI":"10.3390\/ph16060901"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"100486","DOI":"10.1016\/j.jbc.2021.100486","article-title":"The active form of the influenza cap-snatching endonuclease inhibitor baloxavir marboxil is a tight binding inhibitor","volume":"296","author":"Todd","year":"2021","journal-title":"J. Biol. Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1609","DOI":"10.1093\/nar\/gkaa1294","article-title":"Structural insights into the substrate specificity of the endonuclease activity of the influenza virus cap-snatching mechanism","volume":"49","author":"Kumar","year":"2021","journal-title":"Nucleic Acids Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"9633","DOI":"10.1038\/s41598-018-27890-4","article-title":"Characterization of influenza virus variants induced by treatment with the endonuclease inhibitor baloxavir marboxil","volume":"8","author":"Omoto","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1109","DOI":"10.1007\/s40265-020-01350-8","article-title":"Baloxavir Marboxil: A Review in Acute Uncomplicated Influenza","volume":"80","author":"Shirley","year":"2020","journal-title":"Drugs"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"e2206104119","DOI":"10.1073\/pnas.2206104119","article-title":"Identification of cap-dependent endonuclease inhibitors with broad-spectrum activity against bunyaviruses","volume":"119","author":"Toba","year":"2022","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"129175","DOI":"10.1016\/j.bmcl.2023.129175","article-title":"Structure-activity relationship studies of anti-bunyaviral cap-dependent endonuclease inhibitors","volume":"83","author":"Taoda","year":"2023","journal-title":"Bioorg. Med. Chem. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e0018625","DOI":"10.1128\/aac.00186-25","article-title":"A cap-dependent endonuclease inhibitor acts as a potent antiviral agent against La Crosse virus infection","volume":"69","author":"Konishi","year":"2025","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Loutan, A.J., Yang, B., Connolly, G., Montoya, A., Smiley, R.J., Chatterjee, A.K., and G\u00f6tte, M. (2025). Bunyaviral Cap-Snatching Endonuclease Activity and Inhibition with Baloxavir-like Inhibitors in the Context of Full-Length L Proteins. Viruses, 17.","DOI":"10.3390\/v17030420"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"105230","DOI":"10.1016\/j.antiviral.2021.105230","article-title":"Screening and identification of Lassa virus endonuclease-targeting inhibitors from a fragment-based drug discovery library","volume":"197","author":"Lan","year":"2022","journal-title":"Antivir. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1107\/S2052252518001021","article-title":"Crystal structures of Lymphocytic choriomeningitis virus endonuclease domain complexed with diketo-acid ligands","volume":"5","author":"Yekwa","year":"2018","journal-title":"IUCrJ"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1089\/adt.2021.133","article-title":"A New Spectral Shift-Based Method to Characterize Molecular Interactions","volume":"20","author":"Langer","year":"2022","journal-title":"ASSAY Drug Dev. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"W296","DOI":"10.1093\/nar\/gky427","article-title":"SWISS-MODEL: Homology modelling of protein structures and complexes","volume":"46","author":"Waterhouse","year":"2018","journal-title":"Nucleic Acids Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2785","DOI":"10.1002\/jcc.21256","article-title":"AutoDock4 and AutoDockTools4: Automated docking with selective receptor flexibility","volume":"30","author":"Morris","year":"2009","journal-title":"J. Comput. Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"7018","DOI":"10.1038\/s41467-021-27305-5","article-title":"Conformational changes in Lassa virus L protein associated with promoter binding and RNA synthesis activity","volume":"12","author":"Kouba","year":"2021","journal-title":"Nat. Commun."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Dufrasne, F. (2021). Baloxavir Marboxil: An Original New Drug against Influenza. Pharmaceuticals, 15.","DOI":"10.3390\/ph15010028"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2505","DOI":"10.1007\/s11030-022-10567-6","article-title":"Insight into the Hantaan virus RNA-dependent RNA polymerase inhibition using in-silico approaches","volume":"27","author":"Faisal","year":"2023","journal-title":"Mol. Divers."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"22039","DOI":"10.1021\/acs.jmedchem.4c01979","article-title":"Discovery of Novel Thiophene-Based Baloxavir Derivatives as Potent Cap-Dependent Endonuclease Inhibitors for Influenza Treatment","volume":"67","author":"Chen","year":"2024","journal-title":"J. Med. Chem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/j.antiviral.2018.10.008","article-title":"In vitro characterization of baloxavir acid, a first-in-class cap-dependent endonuclease inhibitor of the influenza virus polymerase PA subunit","volume":"160","author":"Noshi","year":"2018","journal-title":"Antivir. Res."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"e0079623","DOI":"10.1128\/jvi.00796-23","article-title":"Identification of tanshinone I as cap-dependent endonuclease inhibitor with broad-spectrum antiviral effect","volume":"97","author":"He","year":"2023","journal-title":"J. Virol."}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/6\/1377\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T04:26:03Z","timestamp":1782534363000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/14\/6\/1377"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,22]]},"references-count":35,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["microorganisms14061377"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms14061377","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,22]]}}}