Abstract

A Gram-stain-positive, aerobic and yellow actinobacterial strain, designated SYP-A7303(T), was isolated from the root of Ginkgo biloba L. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SYP-A7303(T) belongs to the genus Nocardioides. The 16S rRNA gene sequence of strain SYP-A7303(T) showed highest similarity to Nocardioides marinus CL-DD14(T) (=JCM 15615(T)) (98.3 %) and Nocardioides aquiterrae GW-9(T) (=JCM 11813(T)) (97.1 %), and less than 96.9% to the type strains of other species of the genus Nocardioides. Strain SYP-A7303(T) grew optimally at 28 degrees C, pH 7.0 and in the absence of NaCl. It contained LL-2,6-diaminopimelic acid in the cell-wall peptidoglycan, with mannose, ribose, rhamnose, glucose and galactose as whole-cell sugars. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unknown lipid. The menaquinone was MK-8(H-4) and the predominant cellular fatty acids were iso-C-16 : 0, C-18 : 1 omega 9c and C-17 : 1 omega 8c. The DNA G+C content was 72 mol%. Mean DNA-DNA relatedness values between strain SYP-A7303(T) and the closely related strains N. marinus JCM 15615(T) and N. aquiterrae JCM 11813(T) were 62.5 +/- 2.4 and 56.5 +/- 3.5 %, respectively. Based on the morphological, physiological, biochemical and chemotaxonomic characteristics presented in this study, strain SYP-A7303(T) represents a novel species of the genus Nocardioides, for which the name Nocardioides ginkgobilobae sp. nov. is proposed. The type strain is SYP-A7303(T) (=DSM 100492(T) =KCTC 39594(T)).