R Factor Transfer in Rhizobium leguminosarum Beringer, J. E.,, 84, 188-198 (1974), doi = https://doi.org/10.1099/00221287-84-1-188, publicationName = Microbiology Society, issn = 1350-0872, abstract= SUMMARY: R factors of the compatibility class P were transferred between strains of Escherichia coli k12 and Rhizobium leguminosarum. These R factors were stable in R. leguminosarum and conferred similar levels of antibiotic resistance to those in the corresponding R+ E. coli k12 hosts, with the exception of carbenicillin resistance which was greatly reduced. Transfer between R. leguminosarum strains was by conjugation and was stimulated by conditions favouring spheroplast formation. R factor mediated recombination could not be demonstrated., language=, type=