... cofactor, and has a much greater catalytic efficiency as a reductase than as a dehydrogenase The catalytic efficiency of RDH13 as a retinaldehyde reductase is significantly lower than that of a related protein ... enzymatic activity was observed after several months of storage HPLC analysis of RDH13 activity The catalytic activity of RDH13–His6 and the RDH13-containing...