Dictionary > Chemiosmotic coupling hypothesis

Chemiosmotic coupling hypothesis

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).
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 hypothesis
See also: chemiosmosis, mitochondrion

You will also like...

An artistic depiction of a human embryo
Growth and Development of a Human Baby

Upon fertilization, a zygote forms and develops into an embryo. This tutorial elaborates on the growth and development f..

Control of body movement
Control of Body Movement

Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

Hormone Production
Hormone Production

Hormones are chemical messengers produced by specialized glands and they were produced by switching on the genes designe..

The process of photosynthesis
Photosynthesis – Photolysis and Carbon Fixation

Photosynthesis is the process that plants undertake to create organic materials from carbon dioxide and water, with the ..

Population Growth and Survivorship
Population Growth and Survivorship

This lesson looks at population attributes, regulation, and growth. It also covers population genetics, particularly gen..

Freshwater Ecology
Freshwater Ecology

Freshwater ecology focuses on the relations of aquatic organisms to their freshwater habitats. There are two forms of co..

Related Articles...

No related articles found

See all Related Topics