Oxidative phosphorylation is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing the chemical energy stored within the nutrients in order to produce adenosine triphosphate (ATP). In eukaryotes, this takes place inside mitochondria. Almost all aerobic organisms carry out oxidative phosphorylation. This pathway is so pervasive because it releases more energy than alternative fermentation processes such as anaerobic glycolysis.
A proton pump is an integral membrane protein pump that builds up a proton gradient across a biological membrane. Proton pumps catalyze the following reaction:
ATPases (EC 3.6.1.3, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, SV40 T-antigen, adenosine 5'-triphosphatase, ATP hydrolase, complex V (mitochondrial electron transport), (Ca2+ + Mg2+)-ATPase, HCO3−-ATPase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion or the inverse reaction. This dephosphorylation reaction releases energy, which the enzyme (in most cases) harnesses to drive other chemical reactions that would not otherwise occur. This process is widely used in all known forms of life.
ATP synthase is a protein that catalyzes the formation of the energy storage molecule adenosine triphosphate (ATP) using adenosine diphosphate (ADP) and inorganic phosphate (Pi). It is classified under ligases as it changes ADP by the formation of P-O bond (phosphodiester bond). The overall reaction catalyzed by ATP synthase is:
F-ATPase, also known as F-Type ATPase, is an ATPase/synthase found in bacterial plasma membranes, in mitochondrial inner membranes, and in chloroplast thylakoid membranes. It uses a proton gradient to drive ATP synthesis by allowing the passive flux of protons across the membrane down their electrochemical gradient and using the energy released by the transport reaction to release newly formed ATP from the active site of F-ATPase. Together with V-ATPases and A-ATPases, F-ATPases belong to superfamily of related rotary ATPases.
MT-ATP8 is a mitochondrial gene with the full name 'mitochondrially encoded ATP synthase membrane subunit 8' that encodes a subunit of mitochondrial ATP synthase, ATP synthase Fo subunit 8. This subunit belongs to the Fo complex of the large, transmembrane F-type ATP synthase. This enzyme, which is also known as complex V, is responsible for the final step of oxidative phosphorylation in the electron transport chain. Specifically, one segment of ATP synthase allows positively charged ions, called protons, to flow across a specialized membrane inside mitochondria. Another segment of the enzyme uses the energy created by this proton flow to convert a molecule called adenosine diphosphate (ADP) to ATP. Subunit 8 differs in sequence between Metazoa, plants and Fungi.
ATPase, subunit C of Fo/Vo complex is the main transmembrane subunit of V-type, A-type and F-type ATP synthases. Subunit C was found in the Fo or Vo complex of F- and V-ATPases, respectively. The subunits form an oligomeric c ring that make up the Fo/Vo/Ao rotor, where the actual number of subunits vary greatly among specific enzymes.
ATP synthase F1 subunit beta, mitochondrial is an enzyme that in humans is encoded by the ATP5F1B gene.
ATP synthase F1 subunit alpha, mitochondrial is an enzyme that in humans is encoded by the ATP5F1A gene.
ATP synthase-coupling factor 6, mitochondrial is an enzyme subunit that in humans is encoded by the ATP5PF gene.
The alpha and beta subunits are found in the F1, V1, and A1 complexes of F-, V- and A-ATPases, respectively, as well as flagellar (T3SS) ATPase and the termination factor Rho. The subunits make up a ring that contains the ATP-hydrolyzing catalytic core. The F-ATPases, V-ATPases and A-ATPases are composed of two linked complexes: the F1, V1 or A1 complex containsthat synthesizes/hydrolyses ATP, and the Fo, Vo or Ao complex that forms the membrane-spanning pore. The F-, V- and A-ATPases all contain rotary motors, one that drives proton translocation across the membrane and one that drives ATP synthesis/hydrolysis.
ATP synthase subunit g, mitochondrial is an enzyme that in humans is encoded by the ATP5MG gene.
Gamma subunit of ATP synthase F1 complex forms the central shaft that connects the Fo rotary motor to the F1 catalytic core. F-ATP synthases are composed of two linked complexes: the F1 ATPase complex is the catalytic core and is composed of 5 subunits, while the Fo ATPase complex is the membrane-embedded proton channel that is composed of at least 3 subunits (A-C), nine in mitochondria.
ATP synthase subunit b, mitochondrial is an enzyme that in humans is encoded by the ATP5PB gene.
ATP synthase subunit e, mitochondrial is an enzyme that in humans is encoded by the ATP5ME gene.
The human gene ATP5PD encodes subunit d of the peripheral stalk part of the enzyme mitochondrial ATP synthase.
ATP synthase subunit delta, mitochondrial, also known as ATP synthase F1 subunit delta or F-ATPase delta subunit is an enzyme that in humans is encoded by the ATP5F1D gene. This gene encodes a subunit of mitochondrial ATP synthase. Mitochondrial ATP synthase catalyzes ATP synthesis, utilizing an electrochemical gradient of protons across the inner membrane during oxidative phosphorylation.
ATP synthase F1 subunit epsilon, mitochondrial is an enzyme that in humans is encoded by the ATP5F1E gene. The protein encoded by ATP5F1E is a subunit of ATP synthase, also known as Complex V. Variations of this gene have been associated with mitochondrial complex V deficiency, nuclear 3 (MC5DN3) and Papillary Thyroid Cancer.
ATP synthase subunit O, mitochondrial is an enzyme that in humans is encoded by the ATP5PO gene.
ATP synthase delta/epsilon subunit is a part of the ATP synthase and the F-ATPase family in general. It is known as the delta subunit in mitochondrial ATP syntheses, and the epsilon subunit in bacterial and chloroplastic ATP syntheses. It is part of the rotor between subunits F1 and FO. Its C terminal domain seems to inhibit ATPase activity of the synthase.
