Intermediate dehydrogenase-oxidase form of xanthine oxidoreductase in rat liver
- 1 July 1979
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 181 (1) , 177-182
- https://doi.org/10.1042/bj1810177
Abstract
A spectrophotometric method for the determination of three forms of xanthine oxidoreductase, namely dehydrogenase (D), dehydrogenase-oxidase (D/O) and oxidase (O), is described. Enzymic fractions obtained from rat liver were found to contain either all three forms, or (under special conditions of preparation) only two forms, D and D/O. The conversion of form D leads to form D/O leads to form O in the presence of Cu2+ ions was shown. Form D/O acted with NAD+ as well as with O2 as electron acceptors, it exhibited greater affinity to NAD+ than to O2, and NAD+ abolished the oxidase activity of this form. Moreover, oxidase activity of form D/O was inhibited by NADH. These facts indicate that NAD+ and O2 compete for the same active site on the enzyme molecule.This publication has 12 references indexed in Scilit:
- Xanthine oxidase activities: Evidence for two catalytically different typesArchives of Biochemistry and Biophysics, 1978
- Tables for the preparation of ammonium sulfate solutionsAnalytical Biochemistry, 1976
- The mechanism of conversion of rat liver xanthine dehydrogenase from an NAD+-dependent form (type D) to an O2-dependent form (type O)Archives of Biochemistry and Biophysics, 1976
- Purification and properties of the NAD+-dependent (type D) and O2-dependent (type O) forms of rat liver xanthine dehydrogenaseArchives of Biochemistry and Biophysics, 1976
- Milk xanthine oxidase type D (dehydrogenase) and type O (oxidase). Purification, interconversion and some propertiesBiochemical Journal, 1973
- A comparison of the specificities of xanthine oxidase and aldehyde oxidaseArchives of Biochemistry and Biophysics, 1972
- The regulation of rat liver xanthine oxidase. Involvement of thiol groups in the conversion of the enzyme activity from dehydrogenase (type D) into oxidase (type O) and purification of the enzymeBiochemical Journal, 1972
- The regulation of xanthine oxidase. Inhibition by reduced nicotinamide–adenine dinucleotide of rat liver xanthine oxidase type D and of chick liver xanthine dehydrogenaseBiochemical Journal, 1970
- The regulation of rat liver xanthine oxidase. Conversion in vitro of the enzyme activity from dehydrogenase (type D) to oxidase (type O).1969
- The Preparation and Properties of Deflavo Xanthine OxidaseJournal of Biological Chemistry, 1969