Chemiosmotic and murburn explanations for aerobic respiration: Predictive capabilities, structure-function correlations and chemico-physical logic.
Arch Biochem Biophys
; 676: 108128, 2019 11 15.
Article
em En
| MEDLINE
| ID: mdl-31622585
ABSTRACT
Since mid-1970s, the proton-centric proposal of 'chemiosmosis' became the acclaimed explanation for aerobic respiration. Recently, significant theoretical and experimental evidence were presented for an oxygen-centric 'murburn' mechanism of mitochondrial ATP-synthesis. Herein, we compare the predictive capabilities of the two models with respect to the available information on mitochondrial reaction chemistry and the membrane proteins' structure-function correlations. Next, fundamental queries are addressed on thermodynamics of mitochondrial oxidative phosphorylation (mOxPhos) (1) Can the energy of oxygen reduction be utilized for proton transport? (2) Is the trans-membrane proton differential harness-able as a potential energy capable of doing useful work? and (3) Whether the movement of miniscule amounts of mitochondrial protons could give rise to a potential of ~200â¯mV and if such an electrical energy could sponsor ATP-synthesis. Further, we explore critically if rotary ATPsynthase activity of Complex V can account for physiological ATP-turnovers. We also answer the question- "What is the role of protons in the oxygen-centric murburn scheme of aerobic respiration?" Finally, it is demonstrated that the murburn reaction model explains the fast kinetics, non-integral stoichiometry and high yield of mOxPhos. Strategies are charted to further demarcate the two explanations' relevance in the cellular physiology of aerobic respiration.
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Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Força Próton-Motriz
/
Modelos Biológicos
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Idioma:
En
Revista:
Arch Biochem Biophys
Ano de publicação:
2019
Tipo de documento:
Article