Pseudonocardia pini sp. nov., an endophytic actinobacterium isolated from roots of the pine tree Callitris preissii

A Gram-positive, aerobic, actinobacterial strain with rod-shaped spores, CAP47R^T, which was isolated from the surface-sterilized root of a native pine tree (Callitris preissii), grown in South Australia is described. The major cellular fatty acid of this strain was iso-H-C_16:1 and major menaquinone was MK-8(H₄). The diagnostic diamino acid in the cell-wall peptidoglycan was identified as meso-diaminopimelic acid. These chemotaxonomic data confirmed the affiliation of strain CAP47R^T to the genus Pseudonocardia. Phylogenetic evaluation based on 16S rRNA gene sequence analysis placed this strain in the family Pseudonocardiaceae, being most closely related to Pseudonocardia xishanensis JCM 17906^T (98.8%), Pseudonocardia oroxyli DSM 44984^T (98.7%), Pseudonocardia thailandensis CMU-NKS-70^T (98.7%), and Pseudonocardia ailaonensis DSM 44979^T (97.9%). The results of the polyphasic study which contain genome comparisons of ANIb, ANIm, and digital DNA-DNA hybridization revealed the differentiation of strain CAP47R^T from the closest species with validated names. This strain represents a novel species and the name proposed for this microorganism is Pseudonocardia pini sp. nov., indicating the source of this actinobacterium from a pine tree. The type strain is CAP47R^T (= DSM 108967^T = NRRL B-65534^T). Genome mining revealed that this strain contained a variety of genes encoding enzymes that can degrade hazardous chemicals.