... retinal, kinetics of the inhibition of xCTBP/xALDH1 by T3was examined by variation of NAD+concentration within the reaction mixture. The Kmvalue, 9 lM, was independent of the concentration of ... comparison, thy-roid hormone, at its physiological concentration, wouldpoorly modulate the enzyme activity of xCTBP/xALDH1.Keywords: cytosolic thyroid-hormone-binding protein;aldehyde dehydrogenase; ... Effect of coenzymes and thyroid hormones on the dual activities of Xenopuscytosolic thyroid-hormone-binding protein (xCTBP) with aldehyde dehydrogenase activityKiyoshi Yamauchi and Jun–ichiro...