Vincent A KnightOhio State University Medical School, United Kingdom
Title: A 3-Dimensional Hypothesis of Oxidative Phosphorylation
The inner mitochondrial membrane potential created by the electron transport chain results in the reduction of molecular oxygen to H2O and phosphorylation of ADP to produce ATP (oxidative phosphorylation). In this hypothesis, the trans-membrane electrical gradient resulting from electron transport induces a conformational change of the F1F0-ATPase, the enzyme responsible for the hydrolysis or synthesis of ATP. The ATPase lies across the inner mitochondrial membrane in close proximity to the electron transport chain. The conformational change envisaged is coupled with a change of hydrogen bonding of a strategic shell of H2O molecules favoring the direction of the reaction:
ADP + Pi + 2H+out ⇌ ATP + H2O + 2H+in
to the right, when ADP reacts with inorganic phosphate (Pi) to produce ATP, and not the reverse . This happens simply when H2O activity of strategically placed water molecules at the surface of the ATPase is reduced. An explanation of the thermodynamics of this ATPase catalysed reaction and the whole coupling process of the inner mitochondrial membrane is presented with a three dimensional arrangement of the macromolecular structures involved.
To be updated