Nakamurella flava sp. nov., a novel endophytic actinobacterium isolated from Mentha haplocalyx Briq.

A Gram-stain-positive, aerobic, coccus-shaped, non-spore-forming actinobacterium, designated strain N5BH11T, was isolated from a surface-sterilized sample of Mentha haplocalyx Briq. collected from Guizhou, PR China and tested by a polyphasic approach to determine its taxonomic position. Strain N5BH11T grew optimally at 30 °C, pH 6.0-7.0. Substrate mycelia and aerial mycelia were not formed, and no diffusible pigments were observed on the media tested. Phylogenetic analysis based on 16S rRNA gene sequence suggested that strain N5BH11T belonged to the genus Nakamurella and had the highest 16S rRNA gene sequence similarity to Nakamurella flavida DS-52T (98.1 %). The DNA G+C content of strain N5BH11T was 71.6 mol%. The average nucleotide identity values between strain N5BH11T and the type strains of Nakamurella panacisegetis, Nakamurella multipartita and Nakamurella lactea were 74.0, 76.5 and 73.6 %, respectively. The estimated DDH values between strain N5BH11T and the type strains of N. panacisegetis, N. multipartita and N. lactea were 20.3%, 21.4 and 20.2 %, respectively. The cell-wall peptidoglycan contained meso-diaminopimelic acid, and MK-8(H4) was the predominant menaquinone. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine and unidentified phospholipids. The major fatty acids were iso-C15 : 0, anteiso-C15 : 0, C16 : 0 and C16 : 1ω7c. On the basis of the results of phylogenetic analysis and phenotypic and chemotaxonomic characteristics, strain N5BH11T represents a novel species of the genus Nakamurella, for which the name Nakamurella flava sp. nov. is proposed. The type strain is N5BH11T (=KCTC 49196T=CGMCC 4.7524T).

Brachybacterium endophyticum sp. nov., a novel endophytic actinobacterium isolated from bark of Scutellaria baicalensis Georgi.

A Gram-positive, aerobic, coccus-shaped, non-spore-forming actinobacterium, designated strain M1HQ-2T, was isolated from a surface-sterilized bark of Scutellaria baicalensis Georgi collected from Guizhou, China and tested using a polyphasic approach to determine its taxonomic position. Strain M1HQ-2T grew at 4-37 °C (optimum, 30 °C), pH 5.0-11.0 (pH 8.0) and in the presence of 0-15 % (w/v) NaCl (1-3 %). Substrate mycelia and aerial mycelia were not formed, and diffusible pigments were not observed on any media tested. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain M1HQ-2T belonged to the genus Brachybacterium and had the highest 16S rRNA gene sequence similarity of 97.6 % to Brachybacteriumsquillarum M-6-3T. Strain M1HQ-2T contained MK-7 as the dominant menaquinone. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The polar lipids profile of strain M1HQ-2T contained diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and an unidentified lipid. The predominant fatty acids were anteiso-C15 : 0 and anteiso-C17 : 0. The DNA G+C content of strain M1HQ-2T was 71.0 mol%. The average nucleotide identity value between strain M1HQ-2T and type strain of Brachybacterium sacelli was 76.7 %. The estimated DNA-DNA hybridization value between strain M1HQ-2T and type strain of B. sacelli was 20.6 %. On the basis of phylogenetic analysis, chemotaxonomic characteristics and phenotypic data, strain M1HQ-2T represents a novel species of the genus Brachybacterium, for which the name Brachybacteriumendophyticum sp. nov. is proposed. The type strain is M1HQ-2T (=KCTC 49087T=CGMCC 1.16391T).