Arthrobacter antarcticus sp. nov., isolated from an Antarctic marine sediment

Abstract

A bacterial strain, SPC26^T, was isolated from a sediment sample of the Southern Ocean off Antarctica. The strain was Gram-staining- and catalase-positive and contained lysine and alanine in the cell-wall peptidoglycan. The major cellular fatty acids were anteiso-C_15:0 (54.92%), iso-C_15:0 (11.47%), anteiso-C_17:0 (6.48%) and anteiso-C_15:1 (6.38%) and the major menaquinones were MK-8, MK-9 and MK-10. The major polar lipids were phosphatidylethanolamine and diphosphatidylglycerol. The G+C content was 68±0.5 mol%. Based on 16S rRNA gene sequence similarities, the nearest phylogenetic neighbours of strain SPC26^T were identified as Arthrobacter gangotriensis Lz1y^T (98.8%), A. sulfureus DSM 20167^T (98.6%), A. psychrophenolicus DSM 15454^T (97.9%) and A. kerguelensis KGN15^T (97.5). With these strains, strain SPC26^T exhibited DNA-DNA relatedness values of 36, 21, 12 and 10%, respectively. Therefore, on the basis of 16S rRNA gene sequence comparisons, phylogenetic analysis, phenotypic characteristics and DNA-DNA relatedness, it is proposed that strain SPC26^T represents a novel species of Arthrobacter, for which the name Arthrobacter antarcticus sp. nov. is proposed, with strain SPC26^T (=LMG 24542^T =NCCB 100228^T) as the type strain.