NADP+-dependent non-phosphorylating glyceraldehyde 3-phosphate dehydrogenase and ALDH family 11
NADP+-dependent non-phosphorylating glyceraldehyde 3-phosphate dehydrogenase (NP-GAPDH, EC=188.8.131.52) catalyzes the irreversible oxidation of glyceraldehyde 3-phosphate to 3-phosphoglycerate generating NADPH for biosynthetic reactions. This CD also includes the Arabidopsis thaliana osmotic-stress-inducible ALDH family 11, ALDH11A3 and similar sequences. In autotrophic eukaryotes, NP-GAPDH generates NADPH for biosynthetic processes from photosynthetic glyceraldehyde-3-phosphate exported from the chloroplast and catalyzes one of the classic glycolytic bypass reactions unique to plants.
Structure:2ESD; Streptococcus mutans NP-GAPDH thioacylenzyme intermediate with reduced cofactor nicotinamide moiety, defined using 3.5 A. - View structure with Cn3D
Comment:The structure reveals that reduction of the cofactor upon acylation leads to an extensive motion of the nicotinamide moiety with a flip of the reduced pyridinium ring away from the active site.