Peter D. Mitchell proposed the chemiosmotic hypothesis in 1961.^[1] The theory suggests essentially that most ATP synthesis in respiring cells comes from the electrochemical gradient across the inner membranes of mitochondria by using the energy of NADH and FADH₂ formed from the breaking down of energy rich molecules such as glucose. Peter D. Mitchell (September 29, 1920- April 10, 1992) was a British biochemist who was awarded the 1978 Nobel Prize for Chemistry for formulation of the chemiosmotic theory of mitochondrial function. ... 1961 (MCMLXI) was a common year starting on Sunday (the link is to a full 1961 calendar). ... Adenosine 5-triphosphate (ATP), discovered in 1929 by Karl Lohmann,[1] is a multifunctional nucleotide primarily known in biochemistry as the molecular currency of intracellular energy transfer. ... Cellular respiration is the process in which the chemical bonds of energy-rich molecules such as glucose are converted into energy usable for life processes. ... Electrochemistry is the study of the electronic and electrical aspects of chemical reactions. ... Electron micrograph of a mitochondrion showing its mitochondrial matrix and membranes In cell biology, a mitochondrion (plural mitochondria) (from Greek μιτος or mitos, thread + κουδριον or khondrion, granule) is an organelle, variants of which are found in most eukaryotic cells. ... Nicotinamide adenine dinucleotide (NAD+) Nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) are two important coenzymes found in cells. ... Riboflavin Flavin is a tricyclic heteronuclear organic ring based on pteridine whose biochemical source is the vitamin riboflavin. ... Glucose (Glc), a monosaccharide (or simple sugar), is one of the most important carbohydrates in biology. ...

Molecules such as glucose are metabolized to produce acetyl CoA as an energy-rich intermediate. The oxidation of acetyl CoA in the mitochondrial matrix is coupled to the reduction of a carrier molecule such as NAD and FAD.^[2] The carriers pass electrons to the electron transport chain (ETC) in the inner mitochondrial membrane, which in turn pass them to other proteins in the ETC. The energy available in the electrons is used to pump protons from the matrix across the inner mitochondrial membrane, storing energy in the form of a transmembrane electrochemical gradient. The protons move back across the inner membrane through the enzyme ATP synthase. The flow of protons back into the matrix of the mitochondrion via ATP synthase provides enough energy for ADP to combine with inorganic phosphate to form ATP. The electrons and protons at the last pump in the ETC are taken up by oxygen to form water. Categories: Biochemistry stubs | Thiols ... The most fundamental reactions in chemistry are the redox processes. ... Nicotinamide adenine dinucleotide (NAD+) Nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP) are two important cofactors found in cells. ... In biochemistry, flavin adenine dinucleotide (FAD) is the precursor molecule to FADH2. ... The electron is a fundamental subatomic particle that carries an electric charge. ... The Electron Transport Chain. ... In cellular biology, an electrochemical gradient refers to the electrical and chemical properties across a membrane. ... An ATP synthase (EC 3. ... Adenosine diphosphate, abbreviated ADP, is a nucleotide. ... Above is a ball-and-stick model of the inorganic phosphate molecule (HPO42−). Colour coding: P (orange); O (red); H (white). ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... Water is a tasteless, odourless substance that is essential to all known forms of life and is known as the universal solvent. ...

This was a radical proposal at the time, and was not well accepted. The prevailing view was that the energy of electron transfer was stored as a stable high potential intermediate, a chemically more conservative concept.

The problem with the older paradigm is that no high energy intermediate was ever found, and the evidence for proton pumping by the complexes of the electron transfer chain grew too great to be ignored. Eventually the weight of evidence began to favor the chemiosmotic hypothesis, and in 1978, Peter Mitchell was awarded the Nobel Prize in Chemistry.^[3] The electron transfer chain (also called the electron transport chain, ETC, e-train, or simply electron transport), is any series of protein complexes and lipid-soluble messengers that convert the reductive potential of energized electrons into a cross-membrane proton gradient. ... This is a list of Nobel Prize laureates in Chemistry from 1901 to 2006. ...

Chemiosmotic coupling is also important for ATP production in chloroplasts^[4] and many bacteria.^[5] Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... Subgroups Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular: bacterium) are microscopic, unicellular organisms. ...

See also

• Mitochondrion
• Chloroplasts
• Chemiosmosis
• Chemiosmotic potential
• Chemiosmotic phosphorylation
• Electron transfer chain
• Cytochrome
• ATP
• Cellular respiration
• Citric acid cycle
• Glycolysis

Electron micrograph of a mitochondrion showing its mitochondrial matrix and membranes In cell biology, a mitochondrion (plural mitochondria) (from Greek μιτος or mitos, thread + κουδριον or khondrion, granule) is an organelle, variants of which are found in most eukaryotic cells. ... Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... The Chemiosmotic Hypothesis is the proposal in 1961, by Peter D. Mitchell, that the mitochondrion functioned as a kind of electrochemical capacitor, using the energy of NADH and FADH2 to create a proton gradient across the mitochondrial membrane and that this energy was used by a reversible proton pump, the... Electrochemical potential is a thermodynamic measure that reflects energy from entropy and electrostatics and is typically invoked in molecular processes that involve diffusion. ... The electron transfer chain (also called the electron transport chain, ETC, e-train, or simply electron transport), is any series of protein complexes and lipid-soluble messengers that convert the reductive potential of energized electrons into a cross-membrane proton gradient. ... Cytochromes are generally membrane-bound proteins that contain heme groups and carry out electron transport or catalyse reductive/oxidative reactions. ... Adenosine 5-triphosphate (ATP), discovered in 1929 by Karl Lohmann,[1] is a multifunctional nucleotide primarily known in biochemistry as the molecular currency of intracellular energy transfer. ... Cellular respiration is the process in which the chemical bonds of energy-rich molecules such as glucose are converted into energy usable for life processes. ... The citric acid cycle (also known as the tricarboxylic acid cycle, the TCA cycle, or the Krebs cycle) is a series of chemical reactions of central importance in all living cells that utilize oxygen as part of cellular respiration. ... Glycolysis is a biochemical pathway by which a molecule of glucose (Glc) is oxidized to two molecules of pyruvic acid (Pyr). ...

References

1. ^ Peter Mitchell (1961). "Coupling of phosphorylation to electron and hydrogen transfer by a chemi-osmotic type of mechanism". Nature 191: 144–148.Entrez PubMed 13771349
2. ^ Alberts, Bruce, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts and Peter Walter (2002). “Proton Gradients Produce Most of the Cell's ATP”, Molecular Biology of the Cell. Garland. ISBN 0-8153-4072-9.
3. ^ The Nobel Prize in Chemistry 1978.
4. ^ Cooper, Geoffrey M.. “Figure 10.22: Electron transport and ATP synthesis during photosynthesis”, The Cell: A Molecular Approach, 2^nd edition, Sinauer Associates, Inc.. ISBN 0-87893-106-62000.
5. ^ Alberts, Bruce, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts and Peter Walter (2002). “Figure 14-32: The importance of H⁺-driven transport in bacteria”, Molecular Biology of the Cell. Garland. ISBN 0-8153-4072-9.