{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T13:11:26Z","timestamp":1792069886314,"version":"4.4.0"},"reference-count":31,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T00:00:00Z","timestamp":1781222400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["1F31AI161785-01A1"],"award-info":[{"award-number":["1F31AI161785-01A1"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"award":["1F31AI161785-01A1"],"award-info":[{"award-number":["1F31AI161785-01A1"]}],"id":[{"id":"https:\/\/ror.org\/043z4tv69","id-type":"ROR","asserted-by":"publisher"}]},{"name":"UAB Division of Infectious Diseases"},{"name":"UAB Institutional T32 Training Program in Immunologic Diseases and Basic Immunology","award":["T32AI007051"],"award-info":[{"award-number":["T32AI007051"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>As part of efforts to identify genes associated with Trichomonas vaginalis resistance to 5-nitroimidazole drugs, thirty cryopreserved T. vaginalis isolates were revived and grown using Diamond\u2019s TYM medium. Minimum lethal concentrations (MLCs) for metronidazole (MTZ), tinidazole (TDZ), and secnidazole (SEC) were determined using a drug susceptibility assay. Transcriptome profiling was performed for 15 MTZ-sensitive (MTZ-S, MLC &lt; 50 \u00b5g\/mL) and 15 MTZ-resistant (MTZ-R, MLC \u2265 50 \u00b5g\/mL) isolates using next-generation RNA sequencing. Bioinformatics analyses identified differentially expressed genes (DEGs). Among the MTZ-R isolates, six exhibited low MLCs of 50 \u00b5g\/mL, five had intermediate MLCs between 100 and 200 \u00b5g\/mL, and four had high MLCs \u2265 400 \u00b5g\/mL. Differential gene expression analysis identified 28, 140, and 73 significantly altered genes in low-, intermediate-, and high-level MTZ resistance groups, respectively, with predominantly upregulated expression patterns. The SEC-resistant (SEC-R) isolates exhibited 136 differentially expressed genes, whereas the TDZ-resistant (TDZ-R) isolates showed minimal transcriptional changes. Focused analyses of iron transport pathways revealed reduced expression of ZIP-family iron import genes, particularly TvZIP4 (TVAG_273550), the strongest predictor of resistance in elastic-net modeling (AUC = 0.795). Resistant isolates also demonstrated coordinated upregulation of iron\u2013sulfur cluster assembly and hydrogenosomal protein-import pathways. Weighted gene co-expression network analysis (WGCNA) identified multiple resistance-associated transcriptional modules correlated with MTZ and SEC MLCs. A comparative transcriptomic\u2013proteomic analysis revealed concordant upregulation of iron\u2013sulfur cluster machinery but discordant regulation of hydrogenosomal cargo proteins, likely supporting a post-transcriptional restriction model. These findings provide a broader mechanistic framework for understanding 5-nitroimidazole resistance in T. vaginalis and identifying candidate biomarkers and pathways that may support future therapeutic and diagnostic development.<\/jats:p>","DOI":"10.3390\/microorganisms14061314","type":"journal-article","created":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T06:53:10Z","timestamp":1781247190000},"page":"1314","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Transcriptomic Signatures of Trichomonas vaginalis Isolates That Exhibit Low, Intermediate, and High In Vitro Resistance to Metronidazole"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8646-3801","authenticated-orcid":false,"given":"Keonte J.","family":"Graves","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4033-1360","authenticated-orcid":false,"given":"Colin","family":"Reily","sequence":"additional","affiliation":[{"name":"Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, USA"},{"name":"Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35233, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0584-5961","authenticated-orcid":false,"given":"W. Evan","family":"Secor","sequence":"additional","affiliation":[{"name":"Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9211-6670","authenticated-orcid":false,"given":"Jan","family":"Novak","sequence":"additional","affiliation":[{"name":"Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35233, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4005-3858","authenticated-orcid":false,"given":"Christina A.","family":"Muzny","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kissinger, P. 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