title: Rhizobium freirei sp. nov., a symbiont of Phaseolus vulgaris that is very effective at fixing nitrogen.
abstract: Common bean (Phaseolus vulgaris L.) can establish symbiotic associations with several Rhizobium species; however, the effectiveness of most strains at fixing nitrogen under field conditions is very low. PRF 81(T) is a very effective strain, usually referred to as Rhizobium tropici and used successfully in thousands of doses of commercial inoculants for the common bean crop in Brazil; it has shown high rates of nitrogen fixation in all areas representative of the crop in the country. Here, we present results that indicate that PRF 81(T), although it belongs to the 'R. tropici group', which includes 10 Rhizobium species, R. tropici, R. leucaenae, R. lusitanum, R. multihospitium, R. miluonense, R. hainanense, R. calliandrae, R. mayense, R. jaguaris and R. rhizogenes, represents a novel species. Several morpho-physiological traits differentiated PRF 81(T) from related species. Differences were also confirmed in the analysis of rep-PCR (sharing less than 45 % similarity with the other species), MLSA with recA, atpD and rpoB genes, and DNA-DNA hybridization. The novel species, for which we propose the name Rhizobium freirei sp. nov., is able to establish effective root nodule symbioses with Phaseolus vulgaris, Leucaena leucocephala, Leucaena esculenta, Crotalaria juncea and Macroptilium atropurpureum. The type strain is PRF 81(T) ( = CNPSo 122(T) = SEMIA 4080(T) = IPR-Pv81(T) = WDCM 440(T)).
authors.affiliation: Universidade Estadual de Londrina, Dept of Biochemistry and Biotechnology, C.P. 6001, 86051-990 Londrina, Paraná, Brazil.|Embrapa Soja, C.P. 231, 86001-970 Londrina, Paraná, Brazil.
authors.forename: Rebeca Fuzinatto
authors.initials: RF
authors.lastname: Dall'Agnol
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: Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Rogel
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: IAPAR, C.P. 481, 86001-970 Londrina, Paraná, Brazil.
authors.forename: Diva Souza
authors.initials: DS
authors.lastname: Andrade
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.|Universidade Estadual de Londrina, Dept of Biochemistry and Biotechnology, C.P. 6001, 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; D001938:Brazil; D004269:DNA, Bacterial / Q000235:genetics; D005227:Fatty Acids / Q000737:chemistry; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D009586:Nitrogen Fixation; D009693:Nucleic Acid Hybridization; D027805:Phaseolus / Q000382:microbiology*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012231:Rhizobium / Q000145:classification* / Q000235:genetics / Q000502:physiology; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D013559:Symbiosis
chemical_list: D004269:DNA, Bacterial; D005227:Fatty Acids; D012336:RNA, Ribosomal, 16S