Nocardia artemisiae sp. nov., an endophytic actinobacterium isolated from a surface-sterilized stem of Artemisia annua L.

A novel actinobacterium, designated YIM 65623(T), was isolated from a surface-sterilized stem of Artemisia annua L. Strain YIM 65623(T) had morphological, biochemical, physiological and chemotaxonomic properties that were consistent with its classification in the genus Nocardia. Growth occurred with 0-7% (w/v) NaCl (optimum 0-3%), at pH 5.0-9.0 (optimum pH 6.0) and at 10-37 °C (optimum 20-28 °C). Comparative 16S rRNA gene sequence analysis showed that strain YIM 65623(T) constituted a distinct sublineage within the genus Nocardia and displayed 94.1-98.2% sequence similarity to members of established species in the genus Nocardia. However, DNA-DNA relatedness and physiological and biochemical characteristics showed that strain YIM 65623(T) could be differentiated from its closest phylogenetic relatives. The G+C content of the genomic DNA was 69.6 mol%. It is proposed that strain YIM 65623(T) be classified as a representative of a novel species, Nocardia artemisiae sp. nov. The type strain is YIM 65623(T) (=DSM 45379(T) =CCTCC AA 209038(T)).