Search results
Results from the WOW.Com Content Network
Oxidative phosphorylation (UK / ɒ k ˈ s ɪ d. ə. t ɪ v /, US / ˈ ɑː k. s ɪ ˌ d eɪ. t ɪ v / [1]) or electron transport-linked phosphorylation or terminal oxidation is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing chemical energy in order to produce adenosine triphosphate (ATP).
The overall process of creating energy in this fashion is termed oxidative phosphorylation. The same process takes place in the mitochondria, where ATP synthase is located in the inner mitochondrial membrane and the F 1-part projects into the mitochondrial matrix. By pumping proton cations into the matrix, the ATP-synthase converts ADP into ATP.
In the process of photosynthesis, the phosphorylation of ADP to form ATP using the energy of sunlight is called photophosphorylation. Cyclic photophosphorylation occurs in both aerobic and anaerobic conditions, driven by the main primary source of energy available to living organisms, which is sunlight.
Phosphorylation of glucose and fructose 6-phosphate uses two ATP from the cytoplasm. Glycolysis pay-off phase 4 Substrate-level phosphorylation 2 NADH 3 or 5 Oxidative phosphorylation: Each NADH produces net 1.5 ATP (instead of usual 2.5) due to NADH transport over the mitochondrial membrane Oxidative decarboxylation of pyruvate 2 NADH 5
Cyclic phosphorylation is important to create ATP and maintain NADPH in the right proportion for the light-independent reactions. The net-reaction of all light-dependent reactions in oxygenic photosynthesis is: 2 H 2 O + 2 NADP + + 3ADP + 3P i → O 2 + 2 H + + 2NADPH + 3ATP. PSI and PSII are light-harvesting complexes.
F-ATPases (F1FO-ATPases) in mitochondria, chloroplasts and bacterial plasma membranes are the prime producers of ATP, using the proton gradient generated by oxidative phosphorylation (mitochondria) or photosynthesis (chloroplasts). [16] F-ATPases lacking a delta/OSCP subunit move sodium ions instead.
This gradient is used by the F O F 1 ATP synthase complex to make ATP via oxidative phosphorylation. ATP synthase is sometimes described as Complex V of the electron transport chain. [10] The F O component of ATP synthase acts as an ion channel that provides for a proton flux back into the mitochondrial matrix. It is composed of a, b and c ...
Chemiosmotic coupling between the energy of sunlight, bacteriorhodopsin and phosphorylation (chemical energy) during photosynthesis in the halophilic archaeal organism Halobacterium salinarum (syn. H. halobium). The archaeal cell wall is omitted. [6] [7] Bacteria and archaea also can use chemiosmosis to generate ATP.