Antrihabitans auranticaus sp. nov., Isolated from a Cave, and Emended Description of the Genus Antrihabitans
摘要
A Gram-reaction-positive, non-spore-forming actinomycete strain was isolated from lava tunnel in Jeju, Republic of Korea, and its taxonomic associations were examined by a polyphasic approach. The novel strain, designated YC2-6T was found to grow at 10–30 °C, pH 5.0–10.0 and 0–2% (w/v) NaCl. The 16S rRNA gene phylogeny showed that strain YC2-6T formed a distinct subline apart from the genus Antrihabitans The morphological characteristics were in line with most of the genus Antrihabitans, in that cells showed a rod-coccus life cycle during growth, but did not produce any mycelium unlike recently described Antrihabitans spumae. The chemotaxonomic traits such as diamino acid and sugars in cell wall with N-glycolylated murein were typical for the genus Antrihabitans. Moreover, strain YC2-6T also had the major menaquinone of MK-8(H4, ω-cycl), the predominant fatty acids of C16:0, summed feature 3 (C16:1ω6c and/or C16:1ω6c; 20.2%) and C18:1ω9c, and phosphatidylethanolamine as the diagnostic polar lipid, which were in agreement with those of the Antrihabitans stalactiti, as the type species of the genus. In addition, strain YC2-6T also contained C16:0 N alchol as an additional fatty acid. The core genome-based phylogeny revealed that strain YC2-6T formed a highly supported clade with the type strain of Antrihabitans stalactiti. The average amino acid identity values with members of the Antrihabitans were ≥ 72.1%. The highest average nucleotide identity and digital DNA-DNA hybridisation values were 75.7% and 20.4%, respectively, with the phylogenomically closest relative, Antrihabitans stalactiti, indicating that strain YC2-6T (= KACC 19821T = DSM 108745T) represents a new species of the genus Antrihabitans, for which the name Antrihabitans aurantiacus sp. nov. is proposed.