Isolation of nod F gene from Frankia spp. symbiotic with alnus species

Frankia spp. are actinomycetes known to have symbiotic relationship with many actinorhizal woody species including Alnus and Eleagnus spp. Although they are known to infect those woody species by the similar mechanisms which Rhizobium and Bradirhizobium colonize legume species, most of the mechanisms concerning the nodule formation have remained unknown. In this study, we examined whether Frankia spp. have the same nod F gene as that of Rhizobium by amplification of the gene with the primers deduced from Rhizobium sequence. The amplification product and subsequent southern hybridization with nod F gene from Rhizobium meliloti confirmed that Frankia also carries the gene(or DNA segment) comparable to nod F gene in Rhizobium.