SORD, also known as L-iditol 2-dehydrogenase or SORD1, is a 357 amino acid member of the zinc-containing alcohol dehydrogenase family. It is widely expressed with highest expression in kidney and in the lens of the eye. SORD enzymatically catalyzes the zinc-dependent interconversion of polyols, such as sorbitol and xylitol, to their respective ketoses. Recombinant human SORD protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.