{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T06:50:30Z","timestamp":1791355830422,"version":"4.3.1"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>\n                    <jats:italic>Klebsiella variicola<\/jats:italic>\n                    (KV) infections are being increasingly reported across diverse geographic regions and linked to high mortality. KV displays substantial geographical heterogeneity in antimicrobial resistance profiles, virulence phenotypes, and genetic backgrounds; genetic variants further promote its adaptability to varied environments. In this study, we isolated a strain designated KV7 from the sputum sample of an ICU patient at a tertiary hospital in Ningxia, China, with species confirmation achieved via whole-genome sequencing. Antimicrobial susceptibility testing was performed using the VITEK 2 Compact automated microbial system. String test, immune cell phagocytosis assay, serum resistance assay, and mouse infection model were applied to evaluate virulence phenotypes. Genomic characterization revealed that KV7 belongs to ST8223 with an unassigned KL type and exhibits hypervirulence while remaining susceptible to tested antibiotics. Its hypervirulence is associated with the virulence plasmid pKV7-vir, which carries numerous virulence factor genes. Multiple mobile genetic elements were also detected on pKV7-vir. Moreover, comparative genomic analysis of KV isolates from China and other countries was performed, laying a theoretical foundation for regional surveillance of this pathogen.\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2026.1961169","type":"journal-article","created":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T05:58:45Z","timestamp":1791352725000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Whole-genome sequence analysis of a clinical hypervirulent Klebsiella variicola strain recovered from a hospital in Ningxia, China"],"prefix":"10.3389","volume":"17","author":[{"given":"Yuting","family":"Kang","sequence":"first","affiliation":[{"name":"Ningxia Key Laboratory of Clinical and Pathogenic Microbiology, Institute of Medical Sciences, General Hospital of Ningxia Medical University","place":["Yinchuan, Ningxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zezhou","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Radiology, General Hospital of Ningxia Medical University","place":["Yinchuan, Ningxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siyu","family":"Ma","sequence":"additional","affiliation":[{"name":"First Clinical Medical College, Ningxia Medical University","place":["Yinchuan, Ningxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Tao","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, General Hospital of Ningxia Medical University","place":["Yinchuan, Ningxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pengtao","family":"Wang","sequence":"additional","affiliation":[{"name":"Ningxia Key Laboratory of Clinical and Pathogenic Microbiology, Institute of Medical Sciences, General Hospital of Ningxia Medical University","place":["Yinchuan, Ningxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,10,7]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"10610","DOI":"10.1038\/s41598-019-46998-9","article-title":"Molecular epidemiology of Klebsiella variicola obtained from different sources","volume":"9","author":"Barrios-Camacho","year":"2019","journal-title":"Sci. Rep."},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.00841-15","article-title":"An investigation into laboratory misidentification of a bloodstream Klebsiella variicola infection","author":"Berry","year":"2015","journal-title":"J. Clin. Microbiol."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1016\/j.vetmic.2004.11.010","article-title":"Identification and antimicrobial susceptibility of 100 Klebsiella animal clinical isolates","volume":"105","author":"Brisse","year":"2005","journal-title":"Vet. Microbiol."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"604031","DOI":"10.3389\/fmicb.2021.604031","article-title":"Multidrug-resistant (MDR) Klebsiella variicola strains isolated in a Brazilian hospital belong to new clones","volume":"12","author":"De Campos","year":"2021","journal-title":"Front. 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Resist."},{"key":"ref27","doi-asserted-by":"publisher","first-page":"35","DOI":"10.1080\/21505594.2020.1859274","article-title":"Hypervirulent and hypermucoviscous extended-spectrum \u03b2-lactamase-producing Klebsiella pneumoniae and Klebsiella variicola in Chile","volume":"12","author":"Morales-Le\u00f3n","year":"2021","journal-title":"Virulence"},{"key":"ref28","doi-asserted-by":"publisher","first-page":"2509","DOI":"10.1007\/s42770-023-01037-8","article-title":"Characterization and biocontrol efficacy of lytic phage (Kpp-1) that infects multidrug resistant Klebsiella variicola","volume":"54","author":"Nikapitiya","year":"2023","journal-title":"Braz. J. Microbiol."},{"key":"ref29","doi-asserted-by":"publisher","first-page":"e0284422","DOI":"10.1128\/spectrum.02844-22","article-title":"Accurate identification of Klebsiella variicola by Maldi-Tof mass spectrometry in clinical microbiology laboratories","volume":"10","author":"Ohama","year":"2022","journal-title":"Microbiol. 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