Hymenobacter artigasi sp. nov., isolated from air sampling in maritime Antarctica

Abstract

A rod-shaped and Gram-stain-negative bacterial strain, 1B^T, was isolated from an air sample collected at King George Island, maritime Antarctica. Strain 1B^T is strictly aerobic, psychrophilic, catalase-positive, oxidase-positive and non-motile. Growth of strain 1B^T is observed at 0-20 °C (optimum, 10 °C), pH 6.0-8.0 (optimum, pH 8.0) and in the presence of 0-1.0% NaCl (optimum, 0.5 % NaCl). Phylogenetic analysis based on 16S rRNA gene sequences places strain 1B^T within the genus Hymenobacter and shows the highest similarity to Hymenobacter antarcticus VUG-A42aa^T (97.5 %). The predominant menaquinone of strain 1B^T is MK-7 and the major fatty acids (>10 %) comprise summed feature 3 (C_{16 : 1} ω7c and/or C_{16 : 1} ω6c; 32.5 %), iso-C_{15 : 0} (17.6 %) and anteiso C_{15 : 0} (12.3 %). The polar lipid profile consists of the major compounds phosphatidylethanolamine, phosphatidylserine, two unidentified aminolipids and one unidentified phospholipid. The DNA G+C content based on the draft genome sequence is 61.2 mol%. Based on the data from the current polyphasic study, 1B^T represents a novel species of the genus Hymenobacter, for which the name Hymenobacter artigasi sp. nov. is suggested. The type strain is 1B^T (=CCM 8970^T=CGMCC 1.16843^T).

Keywords: Hymenobacter; airborne bacteria; bacterial colonization; maritime Antarctica; oligotrophy; psychrophiles.