Pedobacter ardleyensis sp. nov., isolated from soil in Antarctica

Abstract

A red-pigmented, non-motile, Gram-stain-negative, rod-shaped bacterium, strain R2-28T, was isolated from a soil sample collected from Ardley Island, South Shetland Islands, Antarctica, and was characterized taxonomically by using a polyphasic approach. The organism grew optimally at 18 °C in TSB. On the basis of phylogenetic analyses of the 16S rRNA gene sequence, strain R2-28T was most closely related to the genus Pedobacter of the family Sphingobacteriaceae. The highest levels of 16S rRNA gene sequence similarity were found with respect to Pedobacter alluvionis NWER-II11T (95.6 %) and Pedobacter terrae DS-57T (95.2 %). The DNA G+C content was 39.9 mol%, and MK-7 was the only respiratory quinone. The major polar lipids were phosphatidylethanolamine and a sphingolipid. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). These chemotaxonomic and phylogenetic data supported the allocation of strain R2-28T to the genus Pedobacter. Additionally, the results of physiological and biochemical tests allowed phenotypic differentiation of strain R2-28T from species of the genus Pedobacter with validly published names. Therefore, strain R2-28T represents a novel species within the genus Pedobacter, for which the name Pedobacter ardleyensis sp. nov. is proposed. The type strain is R2-28T ( = CCTCC AB 2013365T = LMG 28255T).