Arthrobacter koreensis sp. nov., a novel alkalitolerant bacterium from soil

Abstract

Two Arthrobacter strains CA15-8T and CA5-9, were isolated from spoil, under alkali conditions, and characterized phenotypically, chemotaxonomically and genetically. These alkalitolerant organisms grew over a wide pH range (pH 7.0-12.0), with an optimum at pH 7.0-8.0. The mean G + C content of the DNA of these strains was 63 ± 2 mol%. The strains contained MK-8(H2) and MK-9(H2) as the main respiratory quinones. The cell-wall peptidoglycan was Lys-Thr-Ala2 and the whole-cell sugar was rhamnose. The major cellular fatty acids of the isolates were anteiso-C15:0 and iso-C15:0. A phylogenetic analysis, based on 16S rDNA sequence data, revealed that strains CA15-8T and CA15-9 formed an evolutionary lineage distinct from other Arthrobacter species. On the basis of morphological, physiological and chemotaxonomic characteristics, 16S rDNA sequence comparisons and DNA-DNA hybridization data, a novel species of Arthrobacter is proposed, namely Arthrobacter koreensis (type strain CA15-8T=KCTC 9922T=IFO 16787T).