Regulation of the phosphate stress response in Rhizobium meliloti by Pho

A research was conducted to study the responses of Rhizobium meliloti to phosphate stress and to determine the phosphate level at which R. meliloti induces its P stress response. Transposon Tn5 was conjugated from Escherichia coli S17-1 into R. meliloti via the suicide vector pSUP2021. Alfalfa seedlings in sterile growth box units were utilized to determine the symbiosis phenotype of the phoB mutant. Results indicated that the loss of a functional PhoB did not disturb the symbiotic function of R. meliloti regardless of the available phosphate.