┌────────────────────────────────────────────────────────── Escherichia coli H591 (2)  
│                                                         ┌─ Escherichia coli 2362-75 (26)  
┤                                                        ┌┴────────── Escherichia coli M605   
│                                              ┌─────────┴────────── Escherichia coli MS 185-1   
└──────────────────────────────────────────────┤           ┌─ Escherichia coli K12 (81)  
                                               │          ┌┴────────── Escherichia coli MS 146-1   
                                               └┬─────────┴────────── Escherichia coli M718   
                                                └┬─ Escherichia coli (10-345/345) 042 (11)  
                                                 └┬────────── Escherichia coli MS 21-1   
                                                  └┬────────── Escherichia coli TA143   
                                                   └────────── Escherichia coli TA280   
  

  
Dihydroorotate dehydrogenase (EC 1.3.3.1)
 (11)