Komlodi 2022 Abstract Bioblast
3.1. KomlΓ³di Timea, Tretter L (2022) The protonmotive force β not merely membrane potential. Bioblast 2022: BEC Inaugural Conference. In: https://doi.org/10.26124/bec:2022-0001 Β»MitoFit PreprintΒ« |
Link: Bioblast 2022: BEC Inaugural Conference
Komlodi Timea, Tretter Laszlo (2022)
Event: Bioblast 2022
The protonmotive force pmF establishes the link between electrical and chemical components of energy transformation and coupling in oxidative phosphorylation in the mitochondrial electron transfer system. The electrical part is corresponding to the mitochondrial membrane potential ΞΞ¨mt and the chemical part is related to the transmembrane pH gradient ΞpH. Although the contribution of ΞpH to pmF is smaller than that of ΞΞ¨mt, ΞpH plays an important role in mitochondrial transport processes and regulation of reactive oxygen species production. Separate measurement of ΞΞ¨mt and ΞpH allows for calculation of pmF. Methods for monitoring ΞΞ¨mt such as fluorescence dyes are generally available, while determination of ΞpH is more challenging.
In this review, we focus on the application of the fluorescence ratiometric method using the acetoxymethyl ester form of 2,7-biscarboxyethyl-5(6)-carboxyfluorescein (BCECF/AM) for real-time monitoring of the intramitochondrial pH in isolated mitochondria. Knowing the intra- and extramitochondrial pH allows for calculating the ΞpH. Application of specific ionophores such as nigericin or valinomycin, exerts the possibility to dissect the two components of the pmF in different directions. Furthermore, we tried to summarize those mitochondrial processes, such as production of reactive oxygen species, where the ΞpH has an important role.
β’ Keywords: BCECF; intramitochondrial pH; matrix pH; ΞpH; mitochondria, mitochondrial membrane potential, ΞΞ¨mt; nigercin; protonmotive force, pmF; reverse electron transfer, RET; safranin; triphenylphosphonium, TPP+; valinomycin
β’ O2k-Network Lab: HU Budapest Tretter L
Affiliations
- Department of Biochemistry, Semmelweis University, Budapest, Hungary
List of abbreviations, terms and definitions - MitoPedia
Labels: MiParea: Instruments;methods, mt-Membrane
Preparation: Isolated mitochondria
Enzyme: Complex V;ATP synthase
Regulation: ATP production, mt-Membrane potential, pH
Coupling state: LEAK, OXPHOS
HRR: Oxygraph-2k, O2k-Fluorometer, TPP Event: A3