Stackebrandtia endophytica sp nov., an actinobacterium isolated from Tripterygium wilfordii

A novel endophytic actinobacterium, designated strain YIM 64602(T), was isolated from healthy stems of Tripterygium wilfordii. It grew at 15-40 degrees C, pH 6.0-9.0 and in the presence of 0-3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain VIM 64602(T) belongs to the genus Stackebrandtia. Whole-cell hydrolysates of strain YIM 64602(T) contained the amino acid meso-diaminopimelic acid with the sugars mannose, rhamnose and glucose, and a trace of ribose. The major polar lipids were diphosphatidylglycerol, phosphati-dylmethylethanolamine and phosphatidylethanolamine. MK-10(H-6), MK-10(H-4) and MK-11(H-4) were the predominant components in the quinone system. The fatty-acid pattern was mainly composed of the saturated branched-chain acids iso-C-16:0, anteiso-C-17:0, iso-C-10:0 and iso-C-17:0. The DNA G+C content was 72.4 mol%. 16S rRNA gene sequence analysis showed the highest pairwise sequence identity (96.0798.5%) with the members of the genus Stackebrandtia. Strain VIM 64602(T) displayed a DNA-DNA relatedness of 43.9+/-0.4% with the type strain Stackebrandtia albiflava YIM 45751(T). Based on evidence from this polyphasic study, strain YIM 64602(T) (=BCRC 16954(T)=DSM 45928(T)) is considered to represent a novel species of the genus Stackebrandtia, for which the name Stackebrandtia endophytica is proposed.