Figure 2.

Phylogeny-guided structural analysis of the PAT1 active site.A, a dendrogram of PAT1 proteins from plants and a microorganism (Corynebacterium spp.) shows the evolutionary relationship among selected PAT1 enzymes. Active site residues for each PAT1 are shown on the left, and residues in blue were within 5 Å of a docking conformation of anthranilate (panel B, magenta). Amino acid numbering is based on the position in the A. thaliana PAT1 protein. B, most identified active site residues are located on the β2 sheet and the α8 and α9 helices. The black dashed line between the amine of anthranilate and PrPPi (phosphoribosyl-pyrophosphate) shows the point at which the transfer reaction occurs.