┌──────────────── Escherichia coli MS 119-7   
                 ┌┴───────────────── Escherichia coli MS 146-1   
                ┌┴─ Escherichia coli K12 (58)  
               ┌┴───────────────── Escherichia coli 2362-75 (4)  
┌──────────────┴────────────────────────────────── Escherichia coli 1044A (24)  
┤┌─ Escherichia coli H299   
└┤                                 ┌─ Escherichia coli 536 (13)  
 │                ┌────────────────┴───────────────────────────────── Escherichia coli MS 200-1   
 └────────────────┤ ┌───────────────── Escherichia coli SE15   
                  └┬┴─ Escherichia coli 83972 (21)  
                   └┬───────────────── Escherichia coli NC101   
                    └───────────────── Escherichia coli ED1a (1)  
  

  
Nitric oxide-dependent regulator DnrN or NorA
 (12)