Issue 24, 1998

Reaction of milk xanthine oxidase with o-phenanthroline and 1,7-dimethylxanthine: a mechanistic study

Abstract

The kinetics of the reaction of milk xanthine oxidase (XO) with o-phenanthroline and 1,7-dimethylxanthine are investigated by optical and circular dichroism (CD) spectroscopic techniques. o-Phenanthroline and 1,7-dimethylxanthine are observed to react with XO, resulting in a slow decrease in the absorbance and CD signals of the enzyme. The results suggest the existence of a multi-binding mechanism in the reaction of XO with o-phenanthroline with two molecules of the substrate binding to one molecule of the enzyme. However, 1,7-dimethylxanthine binds reversibly with the enzyme with 1∶1 stoichiometry. The kinetic effect experienced individually by the flavin adenine dinucleotide (FAD) chromophore of XO has been separately resolved, and shows that at least one molecule of o-phenanthroline may bind near the FAD centre of the enzyme. 1,7-Dimethylxanthine is expected to bind to the molybdenum centre in analogy with xanthine.

Article information

Article type
Paper

J. Chem. Soc., Dalton Trans., 1998, 4173-4178

Reaction of milk xanthine oxidase with o-phenanthroline and 1,7-dimethylxanthine: a mechanistic study

A. Kumar Sau, M. Sudan Mondal and S. Mitra, J. Chem. Soc., Dalton Trans., 1998, 4173 DOI: 10.1039/A807011C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements