biostudies-literatureUnknown62(6)Dabernig-Heinz JThe environmental bacterium <i>Klebsiella oxytoca</i> displays an alarming increase of antibiotic-resistant strains that frequently cause outbreaks in intensive care units. Due to its prevalence in the environment and opportunistic presence in humans, molecular surveillance (including resistance marker screening) and high-resolution cluster analysis are of high relevance. Furthermore, <i>K. oxytoca</i> previously described in studies is rather a species complex (KoSC) than a single species comprising at least six closely related species that are not easily differentiated by standard typing methods. To reach a discriminatory power high enough to identify and resolve clusters within these species, whole genome sequencing is necessary. The resolution is achievable with core genome multilocus Journal of clinical microbiologye0172523https://www.ebi.ac.uk/biostudies/studies/S-EPMC11237601biostudies-literatureCore genome multilocus sequence typing (cgMLST) applicable to the monophyletic <i>Klebsiella oxytoca</i> species complex.PMC11237601Dabernig-Heinz JPrior KRonning TGLipp MHarmsen DRuppitsch WLeitner EKienesberger SSteinmetz IWagner GEfalseCore genome multilocus sequence typing (cgMLST) applicable to the monophyletic <i>Klebsiella oxytoca</i> species complex.The environmental bacterium <i>Klebsiella oxytoca</i> displays an alarming increase of antibiotic-resistant strains that frequently cause outbreaks in intensive care units. Due to its prevalence in the environment and opportunistic presence in humans, molecular surveillance (including resistance marker screening) and high-resolution cluster analysis are of high relevance. Furthermore, <i>K. oxytoca</i> previously described in studies is rather a species complex (KoSC) than a single species comprising at least six closely related species that are not easily differentiated by standard typing methods. To reach a discriminatory power high enough to identify and resolve clusters within these species, whole genome sequencing is necessary. The resolution is achievable with core genome multilocus 2024-01-01T00:00:00Z2024 Jun2025-04-19T01:04:04.707Z2025-04-07T11:57:15.142ZS-EPMC112376013878028610.1128/jcm.01725-23