FIG. 2.

Genomic organization of the formate-dependent nitrite reduction (nrf) locus in selected gram-negative bacteria. Genomic organizations shown are for the following strains: P. multocida Pm70 (GenBank accession number NC_002663), H. influenzae Rd (GenBank accession number NC_000907), and E. coli K-12 (GenBank accession number NC_000913). Open reading frames are indicated by labeled boxes. Cross-hatched boxes indicate predicted orthologs, and the percentage above each box indicates the level of protein sequence identity to the P. multocida Pm70 protein. The superscript a indicates homology to nrfF_2, and the superscript b indicates homology to nrfF_1 and nrfF_2.