Faculty Collaboration Database

Detection of superoxide anion using an isotopically labeled nitrone spin trap: potential biological applications. FEBS Lett 2000 May 04;473(1):58-62

Date

05/10/2000

Pubmed ID

10802059

DOI

10.1016/s0014-5793(00)01498-8

Scopus ID

2-s2.0-0034604057   140 Citations

Abstract

We describe the synthesis and biological applications of a novel nitrogen-15-labeled nitrone spin trap, 5-ethoxycarbonyl-5-methyl-1-pyrroline N-oxide ([(15)N]EMPO) for detecting superoxide anion. Superoxide anion generated in xanthine/xanthine oxidase (100 nM min(-1)) and NADPH/calcium-calmodulin/nitric oxide synthase systems was readily detected using EMPO, a nitrone analog of 5,5'-dimethyl-1-pyrroline N-oxide (DMPO). Unlike DMPO-superoxide adduct (DMPO-OOH), the superoxide adduct of EMPO (EMPO-OOH) does not spontaneously decay to the corresponding hydroxyl adduct, making spectral interpretation less confounding. Although the superoxide adduct of 5-(diethoxyphosphoryl)-5-methyl-pyrroline N-oxide is more persistent than EMPO-OOH, the electron spin resonance spectra of [(14)N]EMPO-OOH and [(15)N]EMPO-OOH are less complex and easier to interpret. Potential uses of [(15)N]EMPO in elucidating the mechanism of superoxide formation from nitric oxide synthases, and in ischemia/reperfusion injury are discussed.

Author List

Zhang H, Joseph J, Vasquez-Vivar J, Karoui H, Nsanzumuhire C, Martásek P, Tordo P, Kalyanaraman B

Authors

Balaraman Kalyanaraman PhD Chair, Professor in the Biophysics department at Medical College of Wisconsin
Jeannette M. Vasquez-Vivar PhD Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Calmodulin
Citrulline
Cyclic N-Oxides
Electron Spin Resonance Spectroscopy
Half-Life
Hydroxyl Radical
Kinetics
NADP
Nitric Oxide Synthase
Nitrogen Isotopes
Nitrogen Oxides
Reperfusion Injury
Sensitivity and Specificity
Spin Labels
Spin Trapping
Superoxides
Xanthine
Xanthine Oxidase