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  • adenosine
  • P-type ATPases are α-helical bundle primary transporters named based upon their ability to catalyze auto- (or self-) phosphorylation (hence P) of a key conserved aspartate residue within the pump and their energy source, adenosine triphosphate (ATP). (wikipedia.org)
  • pumps
  • During evolution, proton pumps have arisen independently on multiple occasions. (wikipedia.org)
  • Thus, not only throughout nature but also within single cells, different proton pumps that are evolutionarily unrelated can be found. (wikipedia.org)
  • Proton pumps are divided into different major classes of pumps that utilize different sources of energy, have different polypeptide compositions and evolutionary origins. (wikipedia.org)
  • The P1A ATPases are predicted to have 7, and the large subfamily of heavy metal pumps P1B) is predicted to have 8 transmembrane helices. (wikipedia.org)
  • lumen
  • NHEs play an important role in the reabsorption of bicarbonate as well, because they provide proton into the lumen, which is titrated with bicarbonate by carbonic anhydrase in the lumen then comes into the proximal tubular cell in the form of CO 2 . (scirp.org)
  • The plant enzymes probably pump one H+ upon hydrolysis of pyrophosphate, thereby generating a proton motive force, positive and acidic in the tonoplast lumen. (wikipedia.org)
  • The generalized transport reaction catalyzed by H+-PPases is: pyrophosphate (P2) + H2O + H+ (cytoplasm) → inorganic phosphate (2 Pi) + H+ (external milieu or vacuolar lumen). (wikipedia.org)
  • The N-termini are predicted to be in the vacuolar lumen while the C-termini are thought to be in the cytoplasm. (wikipedia.org)
  • Proton pumping can be initialized by PP(i) hydrolysis, and H+ is then transported into the vacuolar lumen through a pathway consisting of Arg 242, Asp 294, Lys 742 and Glu 301. (wikipedia.org)
  • pyrophosphatases
  • The archaeon, Methanosarcina mazei Gö1, encodes within its genome two H+-translocating pyrophosphatases (PPases), Mvp1 and Mvp2. (wikipedia.org)
  • Two types of inorganic diphosphatase, very different in terms of both amino acid sequence and structure, have been characterised to date: soluble and transmembrane proton-pumping pyrophosphatases (sPPases and H(+)-PPases, respectively). (wikipedia.org)
  • reaction
  • Proton ATPases are divided into three groups as outlined below: P-type ATPases form a covalent phosphorylated (hence the symbol 'P') intermediate as part of its reaction cycle. (wikipedia.org)
  • The generalized reaction for P-type ATPases is: nLigand1 (out) + mLigand2 (in) + ATP → nLigang1 (in) + mLigand2 (out) + ADP + Pi. (wikipedia.org)
  • driven
  • Complex III ((EC 1.10.2.2)) (also referred to as cytochrome bc1 or the coenzyme Q : cytochrome c - oxidoreductase) is a proton pump driven by electron transport. (wikipedia.org)
  • This proton pump is driven by electron transport and catalyzes the transfer of electrons from plastoquinol to plastocyanin. (wikipedia.org)
  • Complex IV (EC 1.9.3.1) (also referred to as cytochrome c oxidase), is a proton pump driven by electron transport. (wikipedia.org)
  • bicarbonate
  • In the luminal side the key player is sodium-proton exchanger type 3 (NHE3), whereas sodium-bicarbonate cotransporter (NBCe1) plays the critical role in the basolateral side. (scirp.org)
  • In the intercalated cells of the kidney, V-ATPases pump protons into the urine, allowing for bicarbonate reabsorption into the blood. (wikipedia.org)
  • phosphorylation
  • It is interesting to note that the folding pattern and the locations of the critical amino acids for phosphorylation in P-type ATPases has the haloacid dehalogenase fold characteristic of the haloacid dehalogenase (HAD) superfamily, as predicted by sequence homology. (wikipedia.org)
  • processes
  • In humans, P-type ATPases serve as a basis for nerve impulses, relaxation of muscles, secretion and absorption in the kidney, absorption of nutrient in the intestine and other physiological processes. (wikipedia.org)
  • subunits
  • These proteins exhibit a region that shows convincing sequence similarity to the regions surrounding the DCCD-sensitive glutamate in the C-terminal regions of the c-subunits of F-type ATPases (TC #3.A.2). (wikipedia.org)
  • Various subfamilies of P-type ATPases also need additional subunits for proper function. (wikipedia.org)
  • There are at least 13 subunits identified to form a functional V-ATPase complex, which consists of two domains. (wikipedia.org)
  • The Vo domain contains 6 different subunits, a, d, c, c', c", and e, with the stoichiometry of the c ring still a matter of debate with a decamer being postulated for the tobacco Hornworm Manduca sexta V-ATPase. (wikipedia.org)
  • These structures have revealed that the V-ATPase has a 3-stator network, linked by a collar of density formed by the C, H, and a subunits, which, while dividing the V1 and V0 domains, make no interactions with the central rotor axle formed by the F, D, and d subunits. (wikipedia.org)
  • In addition to the structural subunits of yeast V-ATPase, associated proteins that are necessary for assembly have been identified. (wikipedia.org)
  • Like F-type ATPases, V-type ATPases are composed of multiple subunits and carry out rotary catalysis. (wikipedia.org)
  • reaction
  • The generalized reaction for P-type ATPases is: nLigand1 (out) + mLigand2 (in) + ATP → nLigang1 (in) + mLigand2 (out) + ADP + Pi. (wikipedia.org)
  • Proton ATPases are divided into three groups as outlined below: P-type ATPases form a covalent phosphorylated (hence the symbol 'P') intermediate as part of its reaction cycle. (wikipedia.org)
  • lumen
  • The N-termini are predicted to be in the vacuolar lumen while the C-termini are thought to be in the cytoplasm. (wikipedia.org)
  • Proton pumping can be initialized by PP(i) hydrolysis, and H+ is then transported into the vacuolar lumen through a pathway consisting of Arg 242, Asp 294, Lys 742 and Glu 301. (wikipedia.org)
  • yeast
  • The yeast V-ATPase is the best characterized. (wikipedia.org)
  • The complex structure of the V-ATPase has been revealed through the structure of the M. Sexta and Yeast complexes that were solved by single-particle cryo-EM and negative staining, respectively (Muench 2009, Diepholz 2008, Zhang 2008). (wikipedia.org)
  • driven
  • In practice, this is like a simple electric circuit, with a current of protons being driven from the negative N-side of the membrane to the positive P-side by the proton-pumping enzymes of the electron transport chain. (wikipedia.org)
  • NaCl
  • The vacuolar pH of rice roots, determined by 31 P-nuclear magnetic resonance (NMR), increased from 5.34 to 5.58 in response to 0.1 M NaCl treatment. (oup.com)
  • phosphorylation
  • It is interesting to note that the folding pattern and the locations of the critical amino acids for phosphorylation in P-type ATPases has the haloacid dehalogenase fold characteristic of the haloacid dehalogenase (HAD) superfamily, as predicted by sequence homology. (wikipedia.org)
  • processes
  • In humans, P-type ATPases serve as a basis for nerve impulses, relaxation of muscles, secretion and absorption in the kidney, absorption of nutrient in the intestine and other physiological processes. (wikipedia.org)
  • Plasma membrane V-ATPases are involved in processes such as pH homeostasis, coupled transport, and tumor metastasis. (wikipedia.org)
  • Transport
  • It appears that V - ATPase plays a vital role during Na + transport by producing an electromotive force, driving ion transport. (publish.csiro.au)
  • Proton transport becomes electrogenic if not neutralized electrically by transport of either a corresponding negative charge in the same direction or a corresponding positive charge in the opposite direction. (wikipedia.org)
  • gradients
  • Or a pre-LCA ancestor got by with just a PPase, which is equally successful at generating proton energy gradients but is a heck of a lot simpler than the F1F0 ATPase (and shares some homology to boot). (antievolution.org)