Methylotenera oryzisoli sp. Nov., a lanthanide-dependent methylotrophic bacteria isolated from rice field soil

A new lanthanide (Ln³⁺)-dependent methanol-utilizing bacterial strain, La3113^T, was isolated from rice field soil and its taxonomic position was investigated using polyphasic approaches. The strain was aerobic, Gram-stain-negative, strongly motile, catalase-positive and cytochrome oxidase-positive. It could neither catalyse the hydrolysis of urea nor reduce nitrate to nitrite. Growth was observed within a temperature range of 10–40 °C and a pH range of 6–8, with optimum growth at 28 °C and pH 7. Methylamine was utilized as the single source of energy, carbon and nitrogen, and it was oxidized by methylamine dehy-drogenase. C_{16: 1} ω7c, C_{16: 1} ω6c and C_{16: 0} were the dominant cellular fatty acids. Its draft genome (2.67 Mbp and 44.9 mol% G+C content) encodes genes including three Ln³⁺-dependent methanol dehydrogenase (XoxF-type MDH) genes, those for formal-dehyde assimilation (ribulose monophosphate pathway), formate dehydrogenases and methylamine dehydrogenases, but not Ca²⁺-dependent MDH (MxaFI-MDH), which characterizes the species as a Ln³⁺-dependent methylotroph. The 16S rRNA gene sequence showed that strain La3113^T belongs to the genus Methylotenera and is closely related to Methylotenera mobilis JLW8^T (98.29% identity). The digital DNA–DNA hybridization (dDDH) values (less than 30 %) and average nucleotide identity (ANI) values (less than 85 %) between genomes of strain La3113^T and related type strains were lower than the thresholds for species delineation (70% for dDDH and 95–96 % for ANI). On the basis of these polyphasic approaches, we propose a novel Methylotenera species, Methylotenera oryzisoli sp. nov. (type strain La3113^T=NBRC 111954^T=DSM 103219^T).