Sierra Acai Company
Sierra Acai Company
Open 7 Days a Week
MonaVie Independent Distributor
Distributor Training
Shop Online
Enroll Now
Buy Wholesale and maintain an Active status for 2 months and we will refund your $39 Distributor Fee
Friends
Buy Wholesale and maintain an Active status for 2 months and we will refund your $39 Distributor Fee
14-September-2008 18:38:51 - ATP synthase Structure of ATP synthase, the FO proton channel and rotating stalk are shown in blue, the F1 synthase domain in red and the membrane in grey. Structure of ATP synthase, the FO proton channel and rotating stalk are shown in blue, the F1 synthase domain in red and the membrane in grey. An ATP synthase EC 3.6.3.14 is a general term for an enzyme that can synthesize adenosine triphosphate ATP from adenosine diphosphate ADP and inorganic phosphate by using some form of energy. This energy is often in the form of protons moving down an electrochemical gradient, such as from the lumen into the stroma of chloroplasts or from the inter-membrane space into the matrix in mitochondria. The overall reaction sequence is: ADP + Pi → ATP These enzymes are of crucial importance in almost all organisms, because ATP is the common energy currency of cells. The antibiotic oligomycin inhibits the FO unit of ATP synthase. Contents 1 Structure and nomenclature 2 Binding change mechanism 3 Physiological role 4 ATP synthase in different organisms 4.1 Plant ATP synthase 4.2 E. coli ATP synthase 4.3 Yeast ATP synthase 5 Evolution of ATP synthase 6 See also 6.1 Subunits of ATP synthase 7 References 8 External links Structure and nomenclature In mitochondria, the F1FO ATP synthase has a long history of scientific study. the FO portion is within the membrane. The F1 portion of the ATP synthase is above the membrane. It's easy to visualize the FOF1 particle as resembling the fruiting body of a common mushroom, with the head being the F1 particle, the stalk being the gamma subunit of F1, and the base and roots being the FO particle embedded in the membrane. The nomenclature of the enzyme suffers from a long history. The F1 fraction derives it name from the term Fraction 1 and FO written as a subscript O, not zero derives its name from being the oligomycin binding fraction. Taking as an example the nomenclature of subunits in the bovine enzyme, many subunits have alphabet names: Greek letters: alpha, beta, gamma, delta, epsilon Roman letters: a, b, c, d, e, f, g, h Others have more complex names: F6 from Fraction 6 OSCP the oligomycin sensitivity conferral protein, ATP5O A6L named for the gene that codes for it in the mitochondrial genome IF1 inhibitory factor 1, ATPIF1 The F1 particle is large and can be seen in the transmission electron microscope by negative staining.1 These are particles of 9 nm diameter that pepper the inner mitochondrial membrane. They were originally called elementary particles and were thought to contain the entire respiratory apparatus of the mitochondrion, but through a long series of experiments, Ephraim Racker and his colleagues who first isolated the F1 particle in 1961 were able to show that this particle is correlated with ATPase activity in uncoupled mitochondria and with the ATPase activity in submitochondrial particles created by exposing mitochondria to ultrasound. This ATPase activity was further associated with the creation of ATP by a long series of experiments in many laboratories. Binding change mechanism In the 1960s through the 1970s, Paul Boyer developed his binding change, or flip-flop, mechanism, which postulated that ATP synthesis is coupled with a conformational change in the ATP synthase generated by rotation of the gamma subunit. The research group of John E. Walker, then at the MRC Laboratory of Molecular Biology in Cambridge but now at the MRC Dunn Human Nutrition Unit also in Cambridge crystallized the F1 catalytic-domain of ATP synthase. The structure, at the time the largest asymmetric protein structure known, indicated that Boyer's rotary-catalysis model was essentially correct. For elucidating this Boyer and Walker shared half of the 1997 Nobel Prize in Chemistry. Jens Christian Skou received the other half of the Chemistry prize that year for the first discovery of an ion-transporting enzyme, Na+, K+ -ATPase Mechanism of ATP synthase. ATP is shown in red, ADP and phosphate in pink and the rotating γ subunit in black. Mechanism of ATP synthase. ATP is shown in red, ADP and phosphate in pink and the rotating γ subunit in black. The crystal structure of the F1 showed alternating alpha and beta subunits 3 of each, arranged like segments of an orange around an asymmetrical gamma subunit. According to the current model of ATP synthesis known as the alternating catalytic model, the proton-motive force across the inner mitochondrial membrane, generated by the electron transport chain, drives the passage of protons through the membrane via the FO region of ATP synthase. A portion of the FO the ring of c-subunits rotates as the protons pass through the membrane. The c-ring is tightly attached to the asymmetric central stalk consisting primarily of the gamma subunit which rotates within the alpha3beta3 of F1 causing the 3 catalytic nucleotide binding sites to go through a series of conformational changes that leads to ATP synthesis. The major F1 subunits are prevented from rotating in sympathy with the central stalk rotor by a peripheral stalk that joins the alpha3beta3 to the non-rotating portion of FO. The structure of the intact ATP synthase is currently known at low-resolution from electron cryo-microscopy cryo-EM studies of the complex. The cryo-EM model of ATP synthase shows that the peripheral stalk is a flexible rope-like structure that wraps around the complex as it joins F1 to FO. Under the right conditions, the enzyme reaction can also be carried out in reverse, with ATP hydrolysis driving proton pumping across the membrane. The binding change mechanism involves the active site of a β subunit cycling between three states.2 In the open state, ADP and phosphate enter the active site, in the diagram to the right this is shown in brown. The protein then closes up around the molecules and binds them loosely - the loose state shown in red. The enzyme then undergoes another change in shape and forces these molecules together, with the active site in the resulting tight state shown in pink binding the newly-produced ATP molecule with very high affinity. Finally, the active site cycles back to the open state, releasing ATP and binding more ADP and phosphate, ready for the next cycle of ATP production. Physiological role Like other enzymes, the activity of F1FO ATP synthase is reversible. Large enough quantities of ATP cause it to create a transmembrane proton gradient, this is used by fermenting bacteria which do not have an electron transport chain, and hydrolyze ATP to make a proton gradient, which they use for flagella and transport of nutrients into the cell. In respiring bacteria under physiological conditions, ATP synthase generally runs in the opposite direction, creating ATP while using the protonmotive force created by the electron transport chain as a source of energy. 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 so that F1-part sticks into mitochondrial matrix, where ATP synthesis takes place. ATP synthase in different organisms Plant ATP synthase In plants ATP synthase is also present in chloroplasts CF1FO-ATP synthase. The enzyme is integrated into thylakoid membrane; the CF1-part sticks into stroma, where dark reactions of photosynthesis Also called the light-independent reactions or the Calvin cycle and ATP synthesis take place. The overall structure and the catalytic mechanism of the chloroplast ATP synthase are almost the same as those of the mitochondrial enzyme. However, in chloroplasts the proton motive force is generated not by respiratory electron transport chain, but by primary photosynthetic proteins. E. coli ATP synthase E. coli ATP synthase is the simplest known form of ATP synthase, with 8 different subunit types. Yeast ATP synthase Yeast ATP synthase is the most complex known and is made of 20 different types of subunits. Evolution of ATP synthase The evolution of ATP synthase is thought to be an example of modular evolution, where two subunits with their own functions have become associated and gained new functionality. The F1 particle shows significant similarity to hexameric DNA helicases and the FO particle shows some similarity to H+ powered flagellar motor complexes. The α3β3 hexamer of the F1 particle shows significant structural similarity to hexameric DNA helicases; both form a ring with 3 fold rotational symmetry with a central pore. Both also have roles dependent on the relative rotation of a macromolecule within the pore; the DNA helicases use the helical shape of DNA to drive their motion along the DNA molecule and to detect supercoiling whilst the α3β3 hexamer uses the conformational changes due rotation of the γ subunit to drive an enzymatic reaction. The H+ motor of the FO particle shows great functional similarity to the H+ motors seen in flagellar motors. Both feature a ring of many small alpha helical proteins which rotate relative to nearby stationary proteins using a H+ potential gradient as an energy source. This is, however, a fairly tenuous link - the overall structure of flagellar motors is far more complex than the FO particle and the ring of rotating proteins is far larger, with around 30 compared to the 10, 11 or 14 known in the FO complex. The modular evolution theory for the origin of ATP synthase suggests that two subunits with independent function, a DNA helicase with ATPase activity and a H+ motor, were able to bind, and the rotation of the motor drive the ATPase activity of the helicase in reverse. This would then evolve to become more efficient, and eventually develop into the complex ATP synthases seen today. Alternatively the DNA helicase/H+ motor complex may have had H+ pump activity, the ATPase activity of the helicase driving the H+ motor in reverse. This could later evolve to carry out the reverse reaction and act as an ATP synthase. See also Oxidative phosphorylation Mitochondrion Chloroplast Electron transfer chain Proton pump Transmembrane ATPase Flavoprotein P-ATPase Subunits of ATP synthase ATP synthase alpha/beta subunits ATP synthase delta subunit ATP synthase gamma subunit ATP synthase subunit C References ^ Fernandez-Moran et al., Journal of Molecular Biology, Vol 22, p 63, 1962 ^ Gresser MJ, Myers JA, Boyer PD 1982. Catalytic site cooperativity of beef heart mitochondrial F1 adenosine triphosphatase. Correlations of initial velocity, bound intermediate, and oxygen exchange measurements with an alternating three-site model. J. Biol. Chem. 257 20: 12030-8. PMID 6214554. External links ATP synthase - a splendid molecular machine Well illustrated ATP synthase lecture by Antony Crofts of the University of Illinois at Urbana-Champaign. Proton and Sodium translocating F-type, V-type and A-type ATPases in OPM database The Nobel Prize in Chemistry 1997 to Paul D. Boyer and John E. Walker for the enzymatic mechanism of synthesis of ATP; and to Jens C. Skou, for discovery of an ion-transporting enzyme, Na+, K+-ATPase. Harvard Multimedia Production Site - Videos - ATP synthesis animation v d e Acid anhydride hydrolases: ATPases EC 3.6.3-3.6.4 3.6.3 Cu++ Menkes/ATP7A, Wilson/ATP7B Ca+ SERCA, Plasma membrane, ATP2A1, ATP2A2, ATP2A3, ATP2B1, ATP2B2, ATP2B3, ATP2B4, ATP2C1 Na+/K+ ATP1A1, ATP1A2, ATP1A3, ATP1A4, ATP1B1, ATP1B2, ATP1B3, ATP1B4 H+/K+ - ATP synthase - H+ F-type - H+ V-type Other: ATP8B1 - ATP10A - ATP11B - ATP12A - ATP13A2 - ATP13A3 P-type ATPase 3.6.4 Dynein - Kinesin - Myosin v d e Mitochondrial enzymes and transporters Outer membrane fatty acid degradation Carnitine palmitoyltransferase I, Long fatty acyl CoA synthetase tryptophan metabolism Kynureninase monoamine neurotransmitter metabolism Monoamine oxidase Intermembrane space Adenylate kinase - Creatine kinase Inner membrane oxidative phosphorylation Coenzyme Q - cytochrome c reductase, Cytochrome c, NADH dehydrogenase, Succinate dehydrogenase pyrimidine metabolism Dihydroorotate dehydrogenase mitochondrial shuttle Malate-aspartate shuttle, Glycerol phosphate shuttle other Glutamate aspartate transporter, Glycerol-3-phosphate dehydrogenase, ATP synthase, Carnitine palmitoyltransferase II Matrix citric acid cycle Citrate synthase, Aconitase, Isocitrate dehydrogenase, Oxoglutarate dehydrogenase, Succinyl coenzyme A synthetase, Fumarase, Malate dehydrogenase anaplerotic reactions Aspartate transaminase, Glutamate dehydrogenase, Pyruvate dehydrogenase complex urea cycle Carbamoyl phosphate synthetase I, Ornithine transcarbamylase, N-Acetylglutamate synthase alcohol metabolism ALDH2 Other/to be sorted Cholesterol side-chain cleavage enzyme Mitochondrial DNA Complex I 7 units - Complex III 1 unit - Complex IV 3 units - ATP synthase 2 units Retrieved from http://en..org/wiki/ATP_synthase Categories: Enzymes | Cellular respiration | Photosynthesis | EC 3.6.3 | Integral membrane proteins Views Article Discussion this page History Personal tools Log in / create account Navigation Main page Contents Featured content Current events Random article Search Go Search Interaction Community portal Recent changes Contact Donate to Help Toolbox What links here Related changes Upload file Special pages Printable version Permanent link Cite this page Languages Català Deutsch Español Français Italiano 日本語 Polski Português РуÑ?Ñ?кий Sardu Basa Sunda Svenska УкраїнÑ?ька ä¸æ–‡ This page was last modified on 25 August 2008, at 21:14
39 Reasons to Drink Acai Juice Every Day
What is MonaVie - Watch the 8-minute video
Discovering MonaVie Video
The Power of You Video
Effects of MonaVie Active on Antioxidant Capacity in Humans
Log into your Wholesale MonaVie Account
So many of us do not eat a balanced diet, get enough sleep, have too much stress, or are impacted with toxins and pollutants. Drinking 2 ounces of MonaVie twice a day will help your body detoxify as well as build your immune system. Its the smartest thing you can do for yourself, so start today. Buying MonaVie through our company guarantees you support 7 days a week and, if you would like to share MonaVie with your family and friends we will guide you from start to finish.
1. Click on Enroll Now (30 - 55% off retail price)
2. Pay $39 for your Wholesale ID number.
3. NO minimum order required.
4. MonaVie is delivered to your door in 3 to 5 days.