title: Polyphasic evidence supporting the reclassification of Bradyrhizobium japonicum group Ia strains as Bradyrhizobium diazoefficiens sp. nov.
abstract: Bradyrhizobium japonicum was described from soybean root-nodule bacterial isolates. Since its description, several studies have revealed heterogeneities among rhizobia assigned to this species. Strains assigned to B. japonicum group Ia have been isolated in several countries, and many of them are outstanding soybean symbionts used in inoculants worldwide, but they have also been isolated from other legume hosts. Here, we summarize published studies that indicate that group Ia strains are different from the B. japonicum type strain USDA 6(T) and closely related strains, and present new morphophysiological, genotypic and genomic evidence to support their reclassification into a novel species, for which the name Bradyrhizobium diazoefficiens sp. nov. is proposed. The type strain of the novel species is the well-studied strain USDA 110(T) ( =IAM 13628(T)  =CCRC 13528(T)  =NRRL B-4361(T)  =NRRL B-4450(T)  =TAL 102(T)  =BCRC 13528(T)  =JCM 10833(T)  =TISTR 339(T)  =SEMIA 5032(T)  =3I1B110(T)  =ACCC 15034(T)  =CCT 4249(T)  = NBRC 14792(T)  = R-12974(T)  = CNPSo 46(T)).
authors.affiliation: Universidade Estadual de Londrina, Dept of Microbiology, C.P. 60001, 86051-990 Londrina, Paraná, Brazil.|Embrapa Soja, C.P. 231, 86001-970 Londrina, Paraná, Brazil.
authors.forename: Jakeline Renata Marçon
authors.initials: JRM
authors.lastname: Delamuta
authors.affiliation: Universidade Estadual de Londrina, Dept of Microbiology, C.P. 60001, 86051-990 Londrina, Paraná, Brazil.|Embrapa Soja, C.P. 231, 86001-970 Londrina, Paraná, Brazil.
authors.forename: Renan Augusto
authors.initials: RA
authors.lastname: Ribeiro
authors.affiliation: Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Ormeño-Orrillo
authors.affiliation: Embrapa Meio Ambiente, C.P. 69, 13820-000 Jaguariúna, São Paulo, Brazil.
authors.forename: Itamar Soares
authors.initials: IS
authors.lastname: Melo
authors.affiliation: Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico.
authors.forename: Esperanza
authors.initials: E
authors.lastname: Martínez-Romero
authors.affiliation: Universidade Estadual de Londrina, Dept of Microbiology, C.P. 60001, 86051-990 Londrina, Paraná, Brazil.|Embrapa Soja, C.P. 231, 86001-970 Londrina, Paraná, Brazil.
authors.forename: Mariangela
authors.initials: M
authors.lastname: Hungria
mesh_terms: D015373:Bacterial Typing Techniques; D020369:Bradyrhizobium / Q000145:classification* / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D007887:Fabaceae / Q000382:microbiology; D005798:Genes, Bacterial; D009586:Nitrogen Fixation; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013559:Symbiosis
chemical_list: D004269:DNA, Bacterial; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S