Fig. 7
a Evaluating four alternative enzymes for the production of glycolic acid from glycolaldehyde. The production of glycolate was always followed through generation of NAD(P)H from the enzymatic oxidation step from glycolaldehyde to glycolic acid using 110 µg Ab αKGSA-DH (black line), 1.5 µg Ab AraE (blue line), 2 µg Ec AldA (green line) and 140 µg Ec YqhD (red line). The reaction mixture contained 50 mM Tris HCl pH 7.0, 10 mM MgCl2, 2 mM NAD or NAD(P), 1 mM DTT, 1 mM xylonolactone, 4 ug Cc XylC, 6 µg Cc XylD and 2 µg Ec YagE. b Glycolaldehyde concentration dependent steady-state kinetics comparison when using Ec AldA (circles) and Ab AraE (squares). The reaction contained 50 mM Tris HCl pH 7.0, 2 mM NAD, 1 mM DTT, glycolaldehyde 0–2 mM, 2 µg Ec AldA or 1.5 µg Ab AraE