biostudies-literatureUnknown75(1)Iversen XESDanmarks Frie ForskningsfondFour novel nontuberculous mycobacteria were discovered from a historical strain collection at the International Reference Laboratory of Mycobacteriology at Statens Serum Institut in Copenhagen, Denmark. Phylogenetic analysis combining the 16S <i>rrs</i>, internal transcribed spacer and 23S <i>rrl</i> elements, as well as a single-copy core-gene (<i>hsp65</i>, <i>rpoB+C</i>, <i>secA</i> and <i>tuf</i>) analysis of these freeze-dried mycobacteria, clinically isolated from gastric lavage samples between 1948 and 1955, showed to be associated with type strains grouping within the Terra and Fortuitum-Vaccae clade. Phenotypic characteristics, biochemical properties and fatty acid and mycolic acid profiles supported the classification as novel strains. A genomic comparison to the closest related type strain was done by calculating average nucleotide identity and <i>in silico</i> DNA:DNA hybridization values, which showed 87.9% and 33.0% for Mu0050, 85.2% and 27.4% for Mu0053, 85.3% and 27.6% for Mu0083 and 93.3% and 50.1% for Mu0102, respectively. The names proposed for the new species are <i>Mycobacterium wendilense</i> sp. nov. (Mu0050^T=ITM 501390^T=CCUG 77525^T), <i>Mycobacterium burgundiense</i> sp. nov. (Mu0053^T=ITM 501391^T=CCUG 77526^T), <i>Mycobacterium kokjensenii</i> sp. nov. (Mu0083^T=ITM 501392^T=CCUG 77527^T) and <i>Mycobacterium holstebronense</i> sp. nov. (Mu0102^T=ITM 501393^T=CCUG 77528^T).International journal of systematic and evolutionary microbiologyhttps://www.ebi.ac.uk/biostudies/studies/S-EPMC11706282biostudies-literatureFour novel nontuberculous mycobacteria species: <i>Mycobacterium wendilense</i> sp. nov., <i>Mycobacterium burgundiense</i> sp. nov., <i>Mycobacterium kokjensenii</i> sp. nov. and <i>Mycobacterium holstebronense</i> sp. nov. revived from a historical Danish strain collection.PMC117062823127-00035BIversen XESSvensson ERasmussen EMLillebaek TMeehan CJFolkvardsen DBJorgensen RNorman AfalseFour novel nontuberculous mycobacteria species: <i>Mycobacterium wendilense</i> sp. nov., <i>Mycobacterium burgundiense</i> sp. nov., <i>Mycobacterium kokjensenii</i> sp. nov. and <i>Mycobacterium holstebronense</i> sp. nov. revived from a historical Danish strain collection.Four novel nontuberculous mycobacteria were discovered from a historical strain collection at the International Reference Laboratory of Mycobacteriology at Statens Serum Institut in Copenhagen, Denmark. Phylogenetic analysis combining the 16S <i>rrs</i>, internal transcribed spacer and 23S <i>rrl</i> elements, as well as a single-copy core-gene (<i>hsp65</i>, <i>rpoB+C</i>, <i>secA</i> and <i>tuf</i>) analysis of these freeze-dried mycobacteria, clinically isolated from gastric lavage samples between 1948 and 1955, showed to be associated with type strains grouping within the Terra and Fortuitum-Vaccae clade. Phenotypic characteristics, biochemical properties and fatty acid and mycolic acid profiles supported the classification as novel strains. A genomic comparison to the closest related type strain was done by calculating average nucleotide identity and <i>in silico</i> DNA:DNA hybridization values, which showed 87.9% and 33.0% for Mu0050, 85.2% and 27.4% for Mu0053, 85.3% and 27.6% for Mu0083 and 93.3% and 50.1% for Mu0102, respectively. The names proposed for the new species are <i>Mycobacterium wendilense</i> sp. nov. (Mu0050^T=ITM 501390^T=CCUG 77525^T), <i>Mycobacterium burgundiense</i> sp. nov. (Mu0053^T=ITM 501391^T=CCUG 77526^T), <i>Mycobacterium kokjensenii</i> sp. nov. (Mu0083^T=ITM 501392^T=CCUG 77527^T) and <i>Mycobacterium holstebronense</i> sp. nov. (Mu0102^T=ITM 501393^T=CCUG 77528^T).2025-01-01T00:00:00Z2025 Jan2026-06-01T10:27:40.18Z2026-04-08T11:29:28.857ZS-EPMC117062823977368810.1099/ijsem.0.006620