FIG. 2.
Putative catalytic residues. (A) Sequence alignment of AFV1-157 and SSVRH-158. Conserved residues are highlighted in red boxes. The three putative catalytic residues, E23, K57, and E86, are labeled with a green point. Sequence alignments were performed with ClustalW (http://www.ebi.ac.uk/Tools/clustalw2/) and are represented with ESPript (17). (B) Visualization of the E23, E86, and K57 side chains as green sticks within the AFV1-157 surface (residues labeled in italics were substituted for alanine). The positive electrostatic potential is represented in blue. The image was generated with Chimera. (C) Close-up view of the putative catalytic residues. The side chains of E23, K57, E86, and surrounding residues are represented by gray sticks in the 2Fo−Fc Fourier map contoured at 1σ. The image was generated with Pymol (http://pymol.sourceforge.net/).