Nocardioides cynanchi sp. nov., isolated from soil of rhizosphere of Cynanchum wilfordii

Abstract

A novel actinobacterial strain, SB3-45^T, was isolated from soil of <i>Cynanchum wilfordii</i> rhizosphere, Jaecheon-si, Chungcheongbuk-do, Republic of Korea. Strain SB3-45^T, was Gram-stain-positive, aerobic and coccoid to short rod-shaped bacterium. Growth occurred at 4-37 °C (optimum 28 °C), pH 5-8 (optimum pH 7) and 0-2.5 % NaCl (optimum 0%). Phylogenetic analysis based on 16S rRNA gene sequence showed that strain SB3-45^T belonged to the genus <i>Nocardioides</i> and was closely related to <i>Nocardioides opuntiae</i> OS-21^T (96.2%) and <i>Nocardioides panacihumi</i> Gsoil 616^T (95.9%). ll-DAP as the diamino acid in the peptidoglycan and the menaquinone MK-8(H₄) as the predominant isoprenoid quinone were detected. The polar lipids of strain SB3-45^T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unidentified phospholipid. The major cellular fatty acids (>5%) of strain SB3-45^T were iso-C_{16 : 0}, C_{18 : 1} ω9c and C_{17 : 0}. Based on phylogenetic, physiological and chemotaxonomic characteristics, strain SB3-45^T represents a novel species of the genus <i>Nocardioides,</i> for which the name <i>Nocardioides cynanchi</i> sp.nov. is proposed. The type strain is SB3-45^T (=KCTC 49133^T=NBRC 114107^T).