Faculty Collaboration Database

Treatment of Cells and Tissues with Chromate Maximizes Mitochondrial 2Fe2S EPR Signals. Int J Mol Sci 2019 Mar 06;20(5)

Date

03/09/2019

Pubmed ID

30845710

Pubmed Central ID

PMC6429069

DOI

10.3390/ijms20051143

Scopus ID

2-s2.0-85062628835 (requires institutional sign-in at Scopus site)   5 Citations

Abstract

In a previous study on chromate toxicity, an increase in the 2Fe2S electron paramagnetic resonance (EPR) signal from mitochondria was found upon addition of chromate to human bronchial epithelial cells and bovine airway tissue ex vivo. This study was undertaken to show that a chromate-induced increase in the 2Fe2S EPR signal is a general phenomenon that can be used as a low-temperature EPR method to determine the maximum concentration of 2Fe2S centers in mitochondria. First, the low-temperature EPR method to determine the concentration of 2Fe2S clusters in cells and tissues is fully developed for other cells and tissues. The EPR signal for the 2Fe2S clusters N1b in Complex I and/or S1 in Complex II and the 2Fe2S cluster in xanthine oxidoreductase in rat liver tissue do not change in intensity because these clusters are already reduced; however, the EPR signals for N2, the terminal cluster in Complex I, and N4, the cluster preceding the terminal cluster, decrease upon adding chromate. More surprising to us, the EPR signals for N3, the cluster preceding the 2Fe2S cluster in Complex I, also decrease upon adding chromate. Moreover, this method is used to obtain the concentration of the 2Fe2S clusters in white blood cells where the 2Fe2S signal is mostly oxidized before treatment with chromate and becomes reduced and EPR detectable after treatment with chromate. The increase of the g = 1.94 2Fe2S EPR signal upon the addition of chromate can thus be used to obtain the relative steady-state concentration of the 2Fe2S clusters and steady-state concentration of Complex I and/or Complex II in mitochondria.

Author List

Antholine WE, Vasquez-Vivar J, Quirk BJ, Whelan HT, Wu PK, Park JI, Myers CR

Authors

Jong-In Park PhD Professor in the Biochemistry 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

Animals
Bronchi
Cattle
Cell Line, Tumor
Chromates
Electron Spin Resonance Spectroscopy
Electron Transport Complex I
Electron Transport Complex II
Epithelial Cells
Humans
Liver
Mice
Mitochondria
Rats
Xanthine Dehydrogenase