• urea cycle
  • The reactions related to the urea cycle produce NADH), and NADH can be produced in two different ways. (wikipedia.org)
  • The reactions of the urea cycle 1 L-ornithine 2 carbamoyl phosphate 3 L-citrulline 4 argininosuccinate 5 fumarate 6 L-arginine 7 urea L-Asp L-aspartate CPS-1 carbamoyl phosphate synthetase I OTC Ornithine transcarbamoylase ASS argininosuccinate synthetase ASL argininosuccinate lyase ARG1 arginase 1 Before the urea cycle begins ammonia is converted to carbamoyl phosphate. (wikipedia.org)
  • We can summarize this by combining the reactions: CO2 + glutamate + aspartate + 3 ATP + 2 NAD++ 3 H2O → urea + α-ketoglutarate + oxalacetate + 2 ADP + 2 Pi + AMP + PPi + 2 NADH The two NADH produced can provide energy for the formation of 5 ATP (cytosolic NADH provides 2.5 ATP with the malate-aspartate shuttle in human liver cell), a net production of two high-energy phosphate bond for the urea cycle. (wikipedia.org)
  • In the cytosol the enzyme functions to metabolize fumarate, which is a byproduct of the urea cycle as well as amino acid catabolism. (wikipedia.org)
  • citric acid
  • The mitochondrial isoenzyme is involved in the Krebs Cycle (also known as the Tricarboxylic Acid Cycle [TCA] or the Citric Acid Cycle), and the cytosolic isoenzyme is involved in the metabolism of amino acids and fumarate. (wikipedia.org)
  • The function of fumarase in the citric acid cycle is to facilitate a transition step in the production of energy in the form of NADH. (wikipedia.org)
  • The NADH generated by the citric acid cycle is fed into the oxidative phosphorylation (electron transport) pathway. (wikipedia.org)
  • Biochemically, prokaryotic heterotrophic metabolism is much more versatile than that of eukaryotic organisms, although many prokaryotes share the most basic metabolic models with eukaryotes, e. g. using glycolysis (also called EMP pathway) for sugar metabolism and the citric acid cycle to degrade acetate, producing energy in the form of ATP and reducing power in the form of NADH or quinols. (wikipedia.org)
  • nitrate
  • The switch from aerobic to nitrate and fumarate respiration or fermentation corresponds to a progressive decrease in ATP yields. (wikipedia.org)
  • This regulation ensures preferential use of electron acceptors with high ATP yields, and is effected by regulators responding to O2, nitrate and fumarate. (wikipedia.org)
  • In anaerobes, other less-oxidizing substances such as sulfate (SO42−), nitrate (NO3−), sulphur (S), or fumarate are used. (wikipedia.org)
  • produces
  • The cycle consumes acetate (in the form of acetyl-CoA) and water, reduces NAD+ to NADH, and produces carbon dioxide as a waste byproduct. (wikipedia.org)
  • coenzymes
  • however, it is the formation of fumarate from S-malate in particular that is less understood due to the high pKa value of the HR (Fig. 1) atom that is removed without the aid of any cofactors or coenzymes. (wikipedia.org)
  • reactions
  • In addition, the cycle provides precursors of certain amino acids, as well as the reducing agent NADH, that are used in numerous other biochemical reactions. (wikipedia.org)
  • presence
  • 2. Vesicles prepared by exposure of spheroplasts to ultrasound contained cytochromes a, b and c , and at 50°C they rapidly oxidized NADH and ascorbate in the presence of tetramethyl- p -phenylenediamine. (biochemj.org)