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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
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Chemiosmotic misunderstandings
1FP-ENAS/Fac. de Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal; UCIBIO@REQUIMTE, BioSIM, Departamento de Biomedicina, Faculdade de Medicina, Universidade do Porto, Porto, Portugal.
Biophysical Chemistry
|July 28, 2020
Summary
The chemiosmotic theory, crucial for understanding bioenergetics, is challenged by recent proposals. This study refutes these challenges, confirming the validity of chemiosmosis using experimental data and theoretical calculations.
Area of Science:
- Bioenergetics
- Biochemistry
- Cellular Respiration
Background:
- The chemiosmotic theory explains ATP generation via proton movement across membranes.
- Recent publications have questioned its validity, proposing alternative energy generation mechanisms like "murburn".
Purpose of the Study:
- To critically evaluate recent challenges to the chemiosmotic theory.
- To assess the proposed "murburn" mechanism.
Main Methods:
- Analysis of theoretical models applying Gauss' law to mitochondrial charge distribution.
- Examination of experimental data related to ATP synthesis.
- New theoretical calculations to validate or refute proposed mechanisms.
Main Results:
- Recent proposals questioning chemiosmosis are inconsistent with established experimental data.
- Theoretical calculations demonstrate the viability of proton movement for ATP generation.
- The proposed "murburn" mechanism is found to be unsupported.
Conclusions:
- The chemiosmotic theory remains a valid and robust explanation for ATP generation in bioenergetics.
- The criticisms and alternative mechanisms lack sufficient evidence and theoretical support.
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