SERS uncovers the link between conformation of cytochrome c heme and mitochondrial membrane potential

Brazhe, N. A.; Nikelshparg, E. I.; Baizhumanov, A. A.; Grivennikova, V. G.; Semenova, A. A.; Novikov, S. M.; Volkov, V. S.; Arsenin, A. V.; Yakubovsky, D. I.; Evlyukhin, A. B.; Bochkova, Z. V.; Goodilin, E. A.; Maksimov, G. V.; Sosnovtseva, O.; Rubin, A. B.

doi:10.1101/2021.01.03.425119

bioRxiv · 10.1101/2021.01.03.425119

SERS uncovers the link between conformation of cytochrome c heme and mitochondrial membrane potential

Brazhe, N. A.·Nikelshparg, E. I.·Baizhumanov, A. A.·Grivennikova, V. G.·Semenova, A. A.·Novikov, S. M.·Volkov, V. S.·Arsenin, A. V.·Yakubovsky, D. I.·Evlyukhin, A. B.·Bochkova, Z. V.·Goodilin, E. A.·Maksimov, G. V.·Sosnovtseva, O.·Rubin, A. B.

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Abstract

The balance between the mitochondrial respiratory chain activity and the cells needs in ATP ensures optimal cellular function. Cytochrome c is an essential component of the electron transport chain (ETC), which regulates ETC activity, oxygen consumption, ATP synthesis and can initiate apoptosis. The impact of conformational changes in cytochrome c on its function is not understood for lack of access to these changes in intact mitochondria. We have developed a novel sensor that uses unique properties of label-free surface-enhanced Raman spectroscopy (SERS) to identify conformational changes in heme of cytochrome c and to elucidate their role in functioning mitochondria. We verify that molecule bond vibrations assessed by SERS is a reliable indicator of the heme conformation during changes in the inner mitochondrial membrane potential and ETC activity. We have found that cytochrome c heme reversibly switches between planar and ruffled conformations in response to the inner mitochondrial membrane potential and H+ concentration in the intermembrane space to regulate the efficiency of the mitochondrial respiratory chain, thus, adjusting the mitochondrial respiration to the cells consumption of ATP and the overall activity. The ability of the proposed SERS-based sensor to track mitochondrial function opens wide perspectives on cell bioenergetics. For Table of Contents Only O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=127 SRC="FIGDIR/small/425119v2_ufig1.gif" ALT="Figure 1"> View larger version (66K): org.highwire.dtl.DTLVardef@eaaf42org.highwire.dtl.DTLVardef@19826f0org.highwire.dtl.DTLVardef@245e8forg.highwire.dtl.DTLVardef@1bc265d_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Brazhe, N. A., Nikelshparg, E. I., Baizhumanov, A. A., Grivennikova, V. G., Semenova, A. A., Novikov, S. M., Volkov, V. S., Arsenin, A. V., Yakubovsky, D. I., Evlyukhin, A. B., Bochkova, Z. V., Goodilin, E. A., Maksimov, G. V., Sosnovtseva, O., Rubin, A. B.. 2021-01-03. SERS uncovers the link between conformation of cytochrome c heme and mitochondrial membrane potential. https://doi.org/10.1101/2021.01.03.425119

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