Purity: > 95% by SDS - PAGE Format: Liquid. In 20mM Tris-HCl buffer (pH 8.0) containing 1mM DTT, 20% glycerol. Inosine-5'-monophosphate dehydrogenase 1, also known as IMPDH1 catalyzes the synthesis of xanthine monophosphate (XMP) from inosine-5'-monophosphate (IMP). Also, IMPDH1 is a ubiquitously expressed enzyme, functioning as a homotetramer, which catalyzed the rate-limiting step in de novo synthesis of guanine nucleotides. As such, it plays an important role in cyclic nucleoside metabolism within photoreceptors. Defects in the IMPDH1 gene are a cause of retinitis pigmentosa type 10. Recombinant human IMPDH1, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.