sp. nov. isolated from the rhizosphere of the switchgrass .

A Gram-staining-negative non endospore-forming strain, PXU-55, was isolated from the rhizosphere of the switchgrass and studied in detail to determine its taxonomic position. The results of 16S rRNA gene sequence analysis indicated that the isolate represented a member of the genus . The isolate shared highest 16S rRNA gene sequence similarities with the type strains of (98.78 %) and (98.64 %). The average nucleotide identity (ANI) and DNA-DNA hybridization (isDDH) values between the PXU-55 genome assembly and the ones of the most closely related type strains of species of the genus were 87.3 and 31.9% (), and 86.1 and 29.9% (). Menaquinone MK-6 was the major respiratory quinone. As major polar lipids, phosphatidylethanolamine, an ornithine lipid and the unidentified polar lipids L2, L3 and L4 lacking a functional group were found. Moderate to minor amounts of another ornithine lipid, the unidentified lipid L1 and a glycolipid were present, as well. The major polyamine is -homospermidine. The fatty acid profiles contained major amounts of iso-C, iso-C 3-OH, iso-C 3-OH, C, summed feature 3 (Cω7 and/or iso-C 2-OH) and various hydroxylated fatty acids in smaller amounts, among them iso C 3-OH, C 3-OH and C 3-OH, which supported the classification of the isolate as a member of the genus . Physiological and biochemical characterisation and ANI calculations with the type strains of the most closely related species allowed a clear phenotypic and genotypic differentiation of the strain. For this reason, we propose that strain PXU-55 (=CIP 111646=CCM 8914) represents a novel species with the name sp. nov.