┌─── Escherichia coli TA280   
                            ┌┴─ Escherichia coli 042 (1)  
            ┌───────────────┴─── Escherichia coli FVEC1302 (3)  
┌───────────┴──────────────────────────────────────────────────────── Escherichia coli (1-116/117) MS 115-1   
┤                                 ┌─ Escherichia coli K12 (52)  
│                                ┌┴─── Escherichia coli IAI1 (1)  
└──────────────────────────┬─────┴─── Escherichia coli 1827-70 (6)  
                           └──┬─── Escherichia coli IAI39 (3)  
                              └──┬─ Escherichia coli H299   
                                 └┬── Escherichia coli B354 (1)  
                                  └──┬─── Escherichia coli 1044A (25)  
                                     └┬───────── Escherichia coli M718   
                                      └────── Escherichia coli TA143   
  

  
Arsenical resistance operon repressor
 (13)