Genome-based reclassification of : emended classification and description of the species .

Taxonomic relationships between , and have long been debated. Results of previous analyses have shown that overall genome relatedness indices (such as average nucleotide identity and core nucleotide identity) between the type strains ATCC 393 and ATCC 15820 were 94.6 and 95.3 %, respectively, which are borderline for species definition. However, the digital DNA‒DNA hybridization value was 57.3 %, which was clearly lower than the species delineation threshold of 70 %, and hence raised the possibility that could be reclassified into two species. To re-evaluate the taxonomic relationship of these taxa, multilocus sequence analysis (MLSA) based on the concatenated five housekeeping gene (, , , and ) sequences, phylogenomic and core genome multilocus sequence typing analyses, gene presence and absence profiles using pan-genome analysis, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling analysis, cellular fatty acid compositions, and phenotype analysis were carried out. The results of phenotypic characterization, MLSA, whole-genome sequence-based analyses and MALDI-TOF MS profiling justified an independent species designation for the strains, and supported an emended the description of the name of (ex Kuznetsov 1956) Dicks . 1996, with ATCC 15820 (=DSM 20178=BCRC 17942) as the type strain.