• 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)
  • nicotinamide
  • The free energy released in this process is used to form the high-energy molecules ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide). (wikipedia.org)
  • In the short-lived roundworm Caenorhabditis elegans, supplementation with oxoacetate increases the ratio of reduced to oxidized nicotinamide adenine dinucleotide (NAD+:NADH) to activate AMPK and FOXO signaling pathways similar to what occurs in calorie restriction. (wikipedia.org)
  • Respiration
  • Klebsiella ), utilization of C 4 -dicarboxylates, such as tartrate, is independent of fumarate respiration and uses a Na + -dependent membrane-bound oxaloacetate decarboxylase. (asmscience.org)
  • The switch from aerobic to nitrate and fumarate respiration or fermentation corresponds to a progressive decrease in ATP yields. (wikipedia.org)
  • nitrate
  • 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)
  • decreases
  • Decreases in the NAD+/NADH ratio has been proposed carbohydrate metabolism-controlled cellular senescence mechanism. (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)