Arthrobacter silvisoli sp. nov., isolated from forest soil.

A novel Gram-stain-positive, strictly aerobic strain, NEAU-SA1, which showed a rod-coccus growth life cycle, was isolated from forest soil from Zhangjiajie, Hunan Province, China. The isolate grew at 10-40 °C (optimum 28 °C), at pH 5.0-10.0 (optimum pH 7.0) and in the presence of up to 5 % (w/v) NaCl, although NaCl was not required for growth. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-SA1 belonged to the genus Arthrobacter and was closely related to Arthrobacter cupressi DSM 24664 (98.1 % similarity). Average nucleotide identity values between NEAU-SA1 and A. cupressi DSM 24664 were 88.91 and 87.41 % by ANIm and ANIb analysis, respectively. The in silico DNA-DNA hybridization value between strain NEAU-SA1 and A. cupressi DSM 24664 was 34.20 %, again indicating they belong to different taxa. The genomic DNA G+C content was 66.74 mol%. The major cellular fatty acids (>10 %) were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two unidentified glycolipids. The predominant menaquinone was MK-9(H2). The peptidoglycan type was A3α with an interpeptide bridge comprising l-Lys and l-Ala. Glucose, ribose and galactose were the whole-cell sugars. On the basis of morphological, physiological, biochemical and chemotaxonomic analysis, strain NEAU-SA1 was classified as representing a novel species in the genus Arthrobacter, for which the name Arthrobacter silvisoli sp. nov. is proposed. The type strain is NEAU-SA1 (=DSM 106716=CCTCC AB 2017271).