Definition
noun
A theory postulated by the biochemist Peter Mitchell in 1961 to describe ATP synthesis by way of a proton electrochemical coupling.
Accordingly, hydrogen ions (protons) are pumped from the mitochondrial matrix to the intermembrane space via the hydrogen carrier proteins while the electrons are transferred along the electron transport chain in the mitochondrial inner membrane. As the hydrogen ions accumulate in the intermembrane space, an energy-rich proton gradient is established. As the proton gradient becomes sufficiently intense the hydrogen ions tend to diffuse back to the matrix (where hydrogen ions are less) via the ATP synthase (a transport protein). As the hydrogen ions diffuse (through the ATP synthase) energy is released which is then used to drive the conversion of ADP to ATP (by phosphorylation).
Supplement
This theory was not previously well accepted until a great deal of evidence for proton pumping by the complexes of the electron transfer chain emerged. This began to favor the chemiosmotic hypothesis, and in 1978, Peter Mitchell was awarded the Nobel Prize in Chemistry.
Also called: chemiosmotic (coupling) hypothesis
See also: chemiosmosis, mitochondrion
Dictionary > Chemiosmotic theory
You will also like...
Lotic Communities & Algae
Lotic communities have conditions that are rather harsh for typical plants. Thus, the diversity of plant species in loti..
Birth of a Human Baby
Following nine months inside the mother's womb is the birth of the baby. Know the different stages of the birthing proce..
Protein Variety
The sequence of amino acids determines the type of protein. Protein is synthesized according to the sequence of nucleoti..
Types and Causes of Brain Damage
This tutorial describes the different types and causes of brain damage. Find out how genetics, physical injury, lack of ..
Plant Cells vs. Animal Cells
Plant cells have plastids essential in photosynthesis. They also have an additional layer called cell wall on their cell..
Abiotic and Biotic Factors
This tutorial deals with the abiotic factors of the freshwater environment that determine what sort of life would be sui..