Genome-based reclassification of Kutzneria albida (Furumai et al. 1968) Stackebrandt et al. 1994 as a later heterotypic synonym of Kutzneria viridogrisea (Okuda et al. 1966) Stackebrandt et al. 1994

A comparison of 16S rRNA gene sequences between Kutzneria albida DSM 43870 T and Kutzneria viridogrisea DSM 43850 T revealed a sequence similarity of 99.8%. The genus Kutzneria includes five species with validly published names. All members of this genus have been isolated from soil samples collected in Japan or Thailand. The type strains K. albida DSM 43870 T (=ATCC 25243 T =IFO 13901 T =JCM 3240 T =NBRC 13901 T =NRRL B-24060 T ) and K. viridogrisea DSM 43850 T (=ATCC 25242 T =IFO 15561 T =JCM 3282 T =NBRC 15561 T =NRRL B-24059 T =VKM Ac-1297 T ) were both isolated from soil samples from Japan. Whole-genome data were used to clarify the taxonomic assignment of these two closely related Kutzneria species. K. albida DSM 43870 T and K. viridogrisea DSM 43850 T share similar phenotypic and chemotaxonomic profiles. The major menaquinone and characteristic polar lipid are MK-9 (II, III-H 4 ) and PII, respectively. Overall genomic relatedness analyses indicated that K. albida DSM 43870 T and K. viridogrisea DSM 43850 T shared average nucleotide identity and digital DNA–DNA hybridization values >95% and >70%, which are the currently accepted thresholds for species-level delineation. Based on the 16S rRNA gene phylogenetic tree and the core-genome phylogenomic trees, K. albida DSM 43870 T and K. viridogrisea DSM 43850 T phylogenetically form a separate, tight cluster apart from other Kutzneria species. Based on the combined evidence, K. albida (Furumai et al . 1968) Stackebrandt et al . 1994 is proposed to be a later heterotypic synonym of K. viridogrisea (Okuda et al . 1966) Stackebrandt et al . 1994.