Phyllobacterium endophyticum sp. nov., isolated from nodules of Phaseolus vulgaris

Abstract

A strain, PEPV15T, was isolated from a nodule on Phaseolus vulgaris grown in soil in northern Spain. Phylogenetic analyses of 16S rRNA and atpD genes showed that this strain belongs to the genus Phyllobacterium . The most closely related species were, in both cases, Phyllobacterium brassicacearum , Phyllobacterium bourgognense and Phyllobacterium trifolii , the type strains of which gave sequence similarities of 98.9, 98.6 and 98.4 %, respectively, in the 16S rRNA gene and 88.1, 87.5 and 88.7 %, respectively, in the atpD gene. PEPV15T contained Q-10 as the major quinone (88 %) and low amounts of Q-9 (12 %). It differed from its closest relatives in its growth in diverse culture conditions and in the assimilation of several carbon sources. The strain was not able to produce nodules in Phaseolus vulgaris. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain represents a novel species of the genus Phyllobacterium for which the name Phyllobacterium endophyticum sp. nov. is proposed; the type strain is PEPV15T ( = LMG 26470T = CECT 7949T). An emended description of the genus Phyllobacterium is also provided.