Sequence alignment among representative members of the AsdA family.

<p>The secondary structure at the top of the alignment corresponds to the <i>E. ictaluri</i> AsdA enzyme (spirals represent α-helix; arrows represent β-sheet). Conserved amino acids residues are indicated in grey. The stars indicated the key catalytic active site residues (Cys-135, Gln-162, Glu-241, Arg-267, and His-274). The AsdA sequences were obtained from NCBI's Entrez Protein database for <i>Edwardsiella ictaluri</i> YP_002935083.1; <i>Edwardsiella tarda</i> YP_003297386.1; <i>Escherichia coli</i> AP_004358.1; <i>Salmonella</i> Typhi NP_807591.1; <i>Salmonella</i> Paratyphi A YP_152515.1; <i>Salmonella</i> Typhimurium AAB69392.1; <i>Shigella flexnieri</i> YP_690789.1; <i>Shigella sonnei</i> YP_312455.1; <i>Citrobacter koseri</i> YP_001456333.1; <i>Enterobacter cancerogenus</i> ZP_05969786.1; <i>Enterobacter</i> sp. YP_001178547.1; <i>Yersinia pestis</i> NP_671174.1; <i>Yersinia ruckeri</i> ZP_04615435.1; <i>Proteus mirabilis</i> YP_002152826.1; <i>Aeromonas hydrophila</i> ABK39477.1; <i>Aeromonas salmonicida</i> YP_001142146.1; <i>Sodalis glossinidius</i> YP_456010.1; <i>Vibrio cholerae</i> YP_001217562.1; <i>Pseudomonas aeruginosa</i> NP_251807.1; <i>Erwinia carovora atrosepticum</i> YP_052242.1.</p>