RT Journal Article SR Electronic(1) A1 Martínez-Hidalgo, Pilar A1 Ramírez-Bahena, Martha Helena A1 Flores-Félix, José David A1 Igual, José M. A1 Sanjuán, Juan A1 León-Barrios, Milagros A1 Peix, Alvaro A1 Velázquez, EncarnaYR 2016 T1 Reclassification of strains MAFF 303099T and R7A into Mesorhizobiumjaponicum sp. nov. JF International Journal of Systematic and Evolutionary Microbiology, VO 66 IS 12 SP 4936 OP 4941 DO https://doi.org/10.1099/ijsem.0.001448 PB Microbiology Society, SN 1466-5034, AB In this work we revise the taxonomic status of the Lotus-nodulating strains MAFF 303099T and R7A isolated in Japan and New Zealand, respectively. Their 16S rRNA gene sequences are identical and show 98.0, 99.7, 99.8 and 99.9 % similarity values with respect to Mesorhizobium loti NZP 2213T, M. jarvisii ATCC 33669T, M. huakuii USDA 4779T (=CCBAU 2609T) and M. erdmanii USDA 3471T, respectively. The analysis of recA and glnII gene sequeces showed that M. jarvisii ATCC 33669T and M. huakuii USDA 4779T (=CCBAU 2609T) are the most closely related strains to MAFF 303099T and R7A, with similarity values suggesting that these two strains belong to a different species for which MAFF 303099T is selected as the type strain. The DNA–DNA relatedness values between strain MAFF 303099T and its closest phylogenetic relatives ranged from 53 to 60 % in average. Strains MAFF 303099T and R7A presented slight differences in the proportions of C18 : 1ω7c 11-methyl and C19 : 0 cyclo ω8c fatty acids with respect to M. jarvisii ATCC 33669T and M. huakuii USDA 4779T, and also in several phenotypic characteristics. Therefore, we propose the reclassification of these two strains into a novel species named Mesorhizobium japonicum sp. nov., with the type strain being MAFF 303099T (=LMG 29417T=CECT 9101T)., UL https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.001448