Pseudarthrobacter albicanus sp. nov., isolated from Antarctic soil.

Abstract

A Gram-stain positive, strictly aerobic, non-motile and rod-shaped strain, NJ-Z5T, was isolated from a soil sample obtained from the Antarctic Peninsula. This strain was taxonomically characterized by a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NJ-Z5T belonged to the genus Pseudarthrobacter and showed the highest similarities to Pseudarthrobacter sulfonivorans ALLT (98.07%), followed by Pseudarthrobacter siccitolerans 4J27T (98.00%), Pseudarthrobacter phenanthrenivorans Sphe3T (97.93%) and Pseudarthrobacter psychrotolerans YJ56T (97.82%). The strain was able to grow at 4–28 °C (optimum, 25 °C), at pH 6.0–8.0 (optimum, pH 7.0) and with 0–1.0% (w/v) NaCl (optimum, 0%). It had catalase activity but no oxidase activity. The chemotaxonomic characteristics of strain NJ-Z5T, which had MK-9 (H2) as its predominant menaquinone and anteiso-C15:0 (58.5%), anteiso-C17:0 (9.9%) and iso-C16:0 (7.0%) as its major fatty acids, were consistent with classification in the genus Pseudarthrobacter . The polar lipid profile of strain NJ-Z5T comprised phosphatidylinositol, diphosphatidylglycerol, phosphatidylglycerol, three unidentified glycolipids and two unidentified phospholipids. The genome of strain NJ-Z5T was 4.57 Mbp with a G+C content of 67.1 mol%. Average nucleotide identity (ANI) values between strain NJ-Z5T and other species of the genus Pseudarthrobacter were found to be low (ANIm <86%, ANIb <80% and OrthoANIu <80 %). Furthermore, digital DNA–DNA hybridization (dDDH) and average amino acid identity (AAI) values between strain NJ-Z5T and the closely related species ranged from 22.7 to 24.0% and from 75.5 to 77.2%, respectively. On the basis of its differential physiological properties, chemotaxonomic characteristics and low ANI, dDDH and AAI results, strain NJ-Z5T is considered to represent a novel species within the genus Pseudarthrobacter , for which the name Pseudarthrobacter albicanus sp. nov. is proposed. The type strain is NJ-Z5T (=CGMCC 1.15636T=KCTC 39722T).