Fig.Ā 1From: Structure-based directed evolution improves S. cerevisiae growth on xylose by influencing in vivo enzyme performanceStructure of the PirXI active site and design of mutant library LibM1. The figure shows the active site structure of PirXI with xylose (yellow) and Mg2+ ions (green spheres) bound (PDB: 5NH7). The target residues (orange) are located near the active site. The catalytic metal (M2) can occupy two positions (M2a and M2b). W307ā² is a residue from a neighboring subunitBack to article page