FIG. 7.

Alignment of promoter regions from rhizobial rpoN genes. The aligned rpoN sequences are from R. meliloti (Rm), R. etli (Re), Rhizobium sp. strain NGR234, and B. japonicum rpoN2 (BjrpoN2). The −10 and −35 regions from the R. meliloli rpoN promoter are overlined, and the transcription start site is indicated by an arrow (43). The inverse/complement of the consensus (Cons) sequence of a −24/−12 promoter is indicated; conserved GC and CC residues are in boldface. Nucleotides identical to the consensus −24/−12 sequence are underlined. Ec, E. coli.