Arthrobacter siccitolerans sp. nov., a highly desiccation-tolerant, xeroprotectant-producing strain isolated from dry soil

Abstract

A novel desiccation-tolerant, xeroprotectant-producing bacterium, designated strain 4J27T, was isolated from a Nerium oleander rhizosphere subjected to seasonal drought in Granada, Spain. Phylogenetic analysis based on 16S rRNA gene sequencing placed the isolate within the genus Arthrobacter , its closest relative being Arthrobacter phenanthrenivorans Shep3 DSM 18606T, with which it showed 99.23 % 16S rRNA gene sequence similarity. DNA–DNA hybridization measurements showed less than 25 % relatedness between strain 4J27T and Arthrobacter phenanthrenivorans DSM 18606T. The DNA base composition of strain 4J27T was 65.3 mol%. The main fatty acids were anteiso C15 : 0, anteiso C17 : 0, C16 : 0 and iso C16 : 0 and the major menaquinone was MK-9 (H2). The peptidoglycan type was A3α with an l-Lys–l-Ser–l-Thr–l-Ala interpeptide bridge. The bacterium tested positive for catalase activity and negative for oxidase activity. Phylogenetic, chemotaxonomic and phenotypic analyses indicated that the desiccation-tolerant strain 4J27T represents a novel species within the genus Arthrobacter , for which the name Arthrobacter siccitolerans is proposed. The type strain is 4J27T ( = CECT 8257T = LMG 27359T).