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. 1978 Jun 1;171(3):653–658. doi: 10.1042/bj1710653

Electron-paramagnetic-resonance spectroscopy of complexes of xanthine oxidase with xanthine and uric acid.

R C Bray, M J Barber, D J Lowe
PMCID: PMC1184010  PMID: 208512

Abstract

Molybdenum(V) e.p.r. signals from reduced functional milk xanthine oxidase molecules (the Rapid signals), obtained in the presence of purine substrates and products, were further investigated [cf. Bray & Vänngård, (1969) Biochem. J. 114, 725-734; Pick & Bray (1969) Biochem. J. 114, 735-742]. Xanthine forms two complexes with the enzyme that are believed to correspond to different orientations of the substrate molecule in the active site. Only one complex appears to undergo the catalytic reaction. Non-productive complexes, analogous to theone with xanthine, are not formed by 1-methylxanthine or purine. Uric acid forms more than one e.p.r.-detectable complex, one of which is analogous to the non-productive xanthine complex. The computer program used for handing the e.p.r. data is described briefly.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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