Microvirga vignae sp. nov., a root nodule symbiotic bacterium isolated from cowpea grown in semi-arid Brazil Radl, Viviane and Simões-Araújo, Jean Luiz and Leite, Jakson and Passos, Samuel Ribeiro and Martins, Lindete Míria Vieira and Xavier, Gustavo Ribeiro and Rumjanek, Norma Gouvêa and Baldani, José Ivo and Zilli, Jerri Edson,, 64, 725-730 (2014), doi = https://doi.org/10.1099/ijs.0.053082-0, publicationName = Microbiology Society, issn = 1466-5026, abstract= 16S rRNA gene sequence analysis of eight strains (BR 3299T, BR 3296, BR 10192, BR 10193, BR 10194, BR 10195, BR 10196 and BR 10197) isolated from nodules of cowpea collected from a semi-arid region of Brazil showed 97 % similarity to sequences of recently described rhizobial species of the genus Microvirga . Phylogenetic analyses of four housekeeping genes (gyrB, recA, dnaK and rpoB), DNA–DNA relatedness and AFLP further indicated that these strains belong to a novel species within the genus Microvirga . Our data support the hypothesis that genes related to nitrogen fixation were obtained via horizontal gene transfer, as sequences of nifH genes were very similar to those found in members of the genera Rhizobium and Mesorhizobium , which are not immediate relatives of the genus Microvirga , as shown by 16S rRNA gene sequence analysis. Phenotypic traits, such as host range and carbon utilization, differentiate the novel strains from the most closely related species, Microvirga lotononidis , Microvirga zambiensis and Microvirga lupini . Therefore, these symbiotic nitrogen-fixing bacteria are proposed to be representatives of a novel species, for which the name Microvirga vignae sp. nov. is suggested. The type strain is BR3299T ( = HAMBI 3457T)., language=, type=