Figure 1.

Physical map of the Bradyrhizobium sp. strain ORS278 puf region and genetic structure of puf and hmuO mutations. (A) The genes are indicated by open boxes. B, pufB; A, pufA; L, pufL; M, pufM. The positions of putative hairpin structures are indicated by open circles. The positions of relevant restriction sites are also shown. P, PstI; X, XhoI; E, EcoRI; B, BamHI; Bg, BglII. (B) The structures of puf and hmuO mutations are shown along with the corresponding strain names. Horizontal arrows indicate the orientation of the cassette containing the reporter gene lacZ and Km^r.