RESUMEN
Three human clinical strains (W9323(T), X0209(T) and X0394) isolated from a lung biopsy, blood and cerebral spinal fluid, respectively, were characterised using a polyphasic taxonomic approach. Comparative analysis of the 16S rRNA gene sequences showed the three strains belong to two novel branches within the genus Kroppenstedtia: 16S rRNA gene sequence analysis of W9323(T) showed close sequence similarity to Kroppenstedtia eburnea JFMB-ATE(T) (95.3 %), Kroppenstedtia guangzhouensis GD02(T) (94.7 %) and strain X0209(T) (94.6 %); sequence analysis of strain X0209(T) showed close sequence similarity to K. eburnea JFMB-ATE(T) (96.4 %) and K. guangzhouensis GD02(T) (96.0 %). Strains X0209(T) and X0394 were 99.9 % similar to each other by 16S rRNA gene sequence analysis. The DNA-DNA relatedness was 94.6 %, confirming that X0209(T) and X0394 belong to the same species. Chemotaxonomic data for strains W9323(T) and X0209(T) were consistent with those described for the members of the genus Kroppenstedtia: the peptidoglycan was found to contain LL-diaminopimelic acid; the major cellular fatty acids were identified as iso-C15 and anteiso-C15; and the major menaquinone was identified as MK-7. Differences in endospore morphology, carbon source utilisation profiles, and cell wall sugar patterns of strains W9323(T) and X0209(T), supported by phylogenetic analysis, enabled us to conclude that the strains each represent a new species within the genus Kroppenstedtia, for which the names Kroppenstedtia pulmonis sp. nov. (type strain W9323(T) = DSM 45752(T) = CCUG 68107(T)) and Kroppenstedtia sanguinis sp. nov. (type strain X0209(T) = DSM 45749(T) = CCUG 38657(T)) are proposed.