All about Oxidative Phosphorylation

by Jonathan Cogley

Oxidative phosphorylation is a metabolic pathway that uses the energy released by the oxidation of nutrients to produce adenosine triphosphate (ATP). Although many forms of life on earth use a range of different nutrients, almost all carry the oxidative phosphorylation produce ATP, the molecule that provides energy for metabolism. This track is probably so pervasive as it is a very effective way to release energy, compared to other processes such as fermentation glycolysis. During the oxidative phosphorylation, electrons are transferred from the electron donor electron acceptors such as oxygen, reactions redox. These reactions redox release of energy, which is used to form the ATP. In eukaryotes, these reactions redox are carried out by a series of complex proteins in the mitochondria, whereas in prokaryotes, these proteins are found in cells ‘internal membranes. These sets of related enzymes are called channels for transporting electrons. In eukaryotes, five major protein complexes are involved; while in prokaryotes many enzymes are present, using a variety of donors and acceptors electronics.

The energy electrons released through this flow of electrons transport chain is used to transport protons across the mitochondrial inner membrane in a process called chemiosmosis. This creates the potential energy in the form of a gradient of pH and electrical potential across the membrane. This store of energy is operated by allowing protons to go through the membrane and in this slope, thanks to a large enzyme called ATP synthase. This enzyme uses this energy to generate ATP adenosine diphosphate (ADP), in a reaction phosphorylation. Exceptionally, ATP synthase is driven by the flow of protons force rotation of a portion of the enzyme; it is a rotary engine mechanics. Although oxidative phosphorylation is an essential part of metabolism, it produces reactive species of oxygen such as superoxide and hydrogen peroxide which lead to the spread of free radicals that damage cells and contribute to aging and disease. The enzymes carry out this metabolic pathway are also the target of many drugs and poisons that hamper their activities.


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