Fig. 5
Comparison of characterized yeast XRs. a Excerpt of a multiple sequence alignment of yeast XRs showing key residues in the cofactor binding site. The KSN-X3-R protein motif implicated in NADPH specificity is highlighted, and mutations introduced into the genes are noted with arrows beside the species name. Identical residues are shown as white text on a red background and similar residues in red text on a white background. The kinetic parameters of each XR are shown where available alongside the parameters determined in this work. The species from which the XR originate are abbreviated as follows: Ct, C. tenuis; Mg, M. guilliermondii; Sp, S. passalidarum; Ss, S. stipitis; Ci, C. intermedia. b The cofactor binding site of C. tenuis XR in complex with NADP+ (PDB ID: 1k8c) and c with NAD+ (PDB ID: 1mi3). The hydrogen bonds stabilizing the NADP+ in the C. tenuis XR structure is shown with black dashes. d A homology model of the C. intermedia XR2 created with PHYRE [82] using the XR from C. tenuis as a template (PDB ID: 1k8c) to visualize the differences in the active site which may contribute to the lack NADP+ specificity