Terrabacter ginsengisoli sp. nov., isolated from ginseng cultivating soil

Abstract

A Gram-positive, strictly aerobic, nonmotile, yellowish, coccus-rod-shaped bacterium (designated Gsoil 653^T) isolated from ginseng cultivating soil was characterized using a polyphasic approach to clarify its taxonomic position. The strain Gsoil 653^T exhibited optimal growth at pH 7.0 on R2A agar medium at 30°C. Phylogenetic analysis based on 16S rRNA gene sequence similarities, indicated that Gsoil 653^T belongs to the genus Terrabacter of the family Humibacillus, and was closely related to Terrabacter tumescens DSM 20308^T (98.9%), Terrabacter carboxydivorans PY2^T (98.9%), Terrabacter terrigena ON10^T (98.8%), Terrabacter terrae PPLB^T (98.6%), and Terrabacter lapilli LR-26^T (98.6%). The DNA G + C content was 70.5 mol%. The major quinone was MK-8(H₄). The primary polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidyl-ethanolamine. The predominant fatty acids were iso-C_15:0, iso-C_16:0, iso-C_14:0, and anteiso-C_15:0, as in the case of genus Terrabacter, thereby supporting the categorization of strain Gsoil 653^T. However, the DNA-DNA relatedness between Gsoil 653^T and closely related strains of Terrabacter species was low at less than 31%. Moreover, strain Gsoil 653^T could be both genotypically and phenotypically distinguished from the recognized species of the genus Terrabacter. This isolate, therefore, represents a novel species, for which the name Terrabacter ginsengisoli sp. nov. is proposed with the type strain Gsoil 653^T (= KACC 19444^T = LMG 30325^T).

Keywords: 16S rRNA gene sequence; Terrabacter ginsengisoli; polyphasic taxonomy.