Creative Enzymes is a professional institution in providing accurate and reliable activity measurement services. Our extensive experiences in providing fast and effective testing methods guarantee the accurate assay results. In addition, Creative Enzymes is also specialized in analyzing enzymes that are rarely measured by other service providers. As one of these enzymes, L-gulonate 3-dehydrogenase, however, has been well characterized and measured by Creative Enzymes, using unique technologies.

L-gulonate 3-dehydrogenase (GDH; EC 1.1.1.45) is one oxidoreductase, which catalyzes the conversion from L-gulonate to 3-dehydro-L-gulonate, producing NADH as a byproduct. GDH exhibits additional dehydrogenase activity towards several other organic acids with 3-hydroxyl groups, such as L-3-hydroxybutyrate and L-threonate. The other common names of this enzyme include:

• L-3-aldonate dehydrogenase;
• L-3-aldonic dehydrogenase;
• L-gulonic acid dehydrogenase;
• L-beta-hydroxyacid dehydrogenase;
• L-beta-hydroxy-acid-NAD⁺-oxidoreductase;
• L-3-hydroxyacid dehydrogenase

L-Gulonate 3-dehydrogenase is an NAD+-dependent enzyme. It has a key role in theurinate cycle, an alternative glucose metabolic pathway that is essential to the biosynthesis of functional molecules such as glucuronide, glycosaminoglycan, and ascorbic acid. The enzyme exists in a variety of tissues of mammals and Drosophila melanogaster. In human, however, GDH is only present in nonlens tissues, and its expression level is downregulated in hepatocellular carcinoma tissues in patients. So far, the only crystallographic structure of L-gulonate 3-dehydrogenase that has been identified is of the enzyme from rabbit. Therefore, further information based on the crystal structure of GDH from other sources is desired to provide better understanding of the functional nature of this nascent group of enzymes. To meet the research need of this enzyme, Creative Enzymes provides proper activity assays that satisfy the increasing gap between the enzymology knowledge and the increasing interests of using the enzyme in biological industries. We have showed reliable spectrophotometric assays to quantify the enzyme activity. Since NAD⁺ and NADH have distinct UV absorption profiles, the catalytic activity of EC 1.1.1.45 can be measured by following either the reduction of NAD⁺ at 260 nm or the oxidation of NADH at 340 nm on a UV/visible spectrometer.

Figure: The crystal structure of the rabbit L-gulonate 3-dehydrogenase.
Reference: Yukuhiko Asada et al. J. Mol. Biol. 2010 401: 906–920

Creative Enzymes is no double a leader the enzyme activity assay field. We have the most advanced equipment and the unparalleled techniques in enzyme activity determination. With the excellent services and high-quality tests, Creative Enzymes grows dramatically with the support of thousands of customers, and we would like to serve your business and win your trust in the near future.