FIGURE 4.

Alignment of the E. coli MTAN (EcMTAN), the C. jejuni MTAN (CjMTAN), the T. thermophilus futalosine hydrolase (TtMqnB), and the S. coelicolor futalosine hydrolase (ScMqnB). Accession numbers are P0AF14, Q0PC20, Q5SKT7, and Q9KXN0, respectively. Numbered residues correspond to key active site residues identified in the E. coli MTAN. Boldface residues with a gray background correspond to key active site residues identified in the E. coli MTAN and their corresponding conserved homologs. White residues with a black background indicate the replacement of the E. coli MTAN Glu-197 with Gln. Asterisks identify residues conserved in all four sequences. The alignment was performed using COBALT (33).