Related Experiment Video
Updated: Aug 9, 2026

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Studies on the mechanism of site I energy conservation
Abstract:
1. Of the several iron-sulfur centers detected in the site I segment of the respiratory chain, centers N-2 and N-1a alone exhibit apparent phosphate-potential dependent half-reduction potentials, indicating their possible involvement in energy conservation. 2. At high phosphate potential, the apparent half-reduction potential of center N-2 shifts positively by 125 +/- 20 mV, while center N-1a shifts negatively by approximately 60 mV. 3. The redox state of individual iron-sulfur centers in various metabolic states was analyzed. Center N-2 is highly reduced (greater than 90%) in "state 4" mitochondria, while center N-1a stays mostly oxidized. 4. In a submitochondrial system, ATP addition induced reduction of center N-2 if the Eh of the suspension was poised from the high potential side of site I using the succinate/fumarate couple. In contrast, center N-2 was oxidized upon energization, if the Eh of the system was poised from the low potential side using the NADH/NAD couple. 5. Based on these redox behaviors of center N-2, a tentative hypothesis of site I energy transduction was proposed.
Related Concept Videos
Conservative Forces
Conservation of Energy
Conservation of Energy: Application
Energy Diagrams - II
The point in the energy diagram at which the system’s potential energy is the lowest is known as the local minima. The system tends to stay in this position indefinitely unless acted upon by a net force. The slope of the potential energy diagram at the local minima is zero, indicating that zero net force is acting on the system. The slope...
Conservation of Mechanical Energy
When a...
Energy Conservation and Bernoulli's Equation
All the terms in the equation have the dimension of energy per unit volume. The kinetic energy per unit volume is called the kinetic energy density, and the potential energy per unit volume is...

