A report on Adenosine triphosphate and Flavin adenine dinucleotide

Interactive animation of the structure of ATP

The cycles of synthesis and degradation of ATP; 2 and 1 represent input and output of energy, respectively.

This image shows a 360-degree rotation of a single, gas-phase magnesium-ATP chelate with a charge of −2. The anion was optimized at the UB3LYP/6-311++G(d,p) theoretical level and the atomic connectivity modified by the human optimizer to reflect the probable electronic structure.

Mechanism 1. Hydride transfer occurs by addition of H+ and 2 e−

An example of the Rossmann fold, a structural domain of a decarboxylase enzyme from the bacterium Staphylococcus epidermidis with a bound flavin mononucleotide cofactor.

Mechanism 2. Hydride transfer by abstraction of hydride from NADH

Mechanism 3. Radical formation by electron abstraction

Mechanism 4. The loss of hydride to electron deficient R group

Mechanism 5. Use of nucleophilic addition to break R1-R2 bond

Mechanism 6. Carbon radical reacts with O2 and acid to form H2O2

Warburg's work with linking nicotinamide to hydride transfers and the discovery of flavins paved the way for many scientists in the 40s and 50s to discover copious amounts of redox biochemistry and link them together in pathways such as the citric acid cycle and ATP synthesis.

- Flavin adenine dinucleotide

NADH and FADH2 are recycled (to NAD+ and FAD, respectively) by oxidative phosphorylation, generating additional ATP.

- Adenosine triphosphate

12 related topics with Alpha

Citric acid cycle

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Series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins.

Structural diagram of acetyl-CoA: The portion in blue, on the left, is the acetyl group; the portion in black is coenzyme A.

The net result of these two closely linked pathways is the oxidation of nutrients to produce usable chemical energy in the form of ATP.

The overall yield of energy-containing compounds from the citric acid cycle is three NADH, one FADH2, and one GTP.

Two mitochondria from mammalian lung tissue displaying their matrix and membranes as shown by electron microscopy

Mitochondrion

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Double-membrane-bound organelle found in most eukaryotic organisms.

Simplified structure of a mitochondrion.

Cross-sectional image of cristae in a rat liver mitochondrion to demonstrate the likely 3D structure and relationship to the inner membrane

Electron transport chain in the mitochondrial intermembrane space

Transmission electron micrograph of a chondrocyte, stained for calcium, showing its nucleus (N) and mitochondria (M).

Typical mitochondrial network (green) in two human cells (HeLa cells)

Model of the yeast multimeric tethering complex, ERMES

The circular 16,569 bp human mitochondrial genome encoding 37 genes, i.e., 28 on the H-strand and 9 on the L-strand.

Mitochondria use aerobic respiration to generate most of the cell's supply of adenosine triphosphate (ATP), which is subsequently used throughout the cell as a source of chemical energy.

The citric acid cycle oxidizes the acetyl-CoA to carbon dioxide, and, in the process, produces reduced cofactors (three molecules of NADH and one molecule of FADH2) that are a source of electrons for the electron transport chain, and a molecule of GTP (which is readily converted to an ATP).

Cellular respiration

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Out of the cytoplasm it goes into the Krebs cycle with the acetyl CoA. It then mixes with CO2 and makes 2 ATP, NADH, and FADH. From there the NADH and FADH go into the NADH reductase, which produces the enzyme. The NADH pulls the enzyme's electrons to send through the electron transport chain. The electron transport chain pulls H+ ions through the chain. From the electron transport chain, the released hydrogen ions make ADP for an result of 32 ATP. O2 provides most of the energy for the process and combines with protons and the electrons to make water. Lastly, ATP leaves through the ATP channel and out of the mitochondria.

Stoichiometry of aerobic respiration and most known fermentation types in eucaryotic cell. Numbers in circles indicate counts of carbon atoms in molecules, C6 is glucose C6H12O6, C1 carbon dioxide CO2. Mitochondrial outer membrane is omitted.

Cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert chemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.

The products of this process are carbon dioxide and water, and the energy transferred is used to break bonds in ADP to add a third phosphate group to form ATP (adenosine triphosphate), by substrate-level phosphorylation, NADH and FADH2

Oxidative phosphorylation

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Reduction of coenzyme Q from its ubiquinone form (Q) to the reduced ubiquinol form (QH2).

Complex I or NADH-Q oxidoreductase. The abbreviations are discussed in the text. In all diagrams of respiratory complexes in this article, the matrix is at the bottom, with the intermembrane space above.

The two electron transfer steps in complex III: Q-cytochrome c oxidoreductase. After each step, Q (in the upper part of the figure) leaves the enzyme.

Mechanism of ATP synthase. ATP is shown in red, ADP and phosphate in pink and the rotating γ subunit in black.

Oxidative phosphorylation (UK, US ) or electron transport-linked phosphorylation or terminal oxidation is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing chemical energy in order to produce adenosine triphosphate (ATP).

The energy stored in the chemical bonds of glucose is released by the cell in the citric acid cycle producing carbon dioxide, and the energetic electron donors NADH and FADH.

Electron transport chain

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Series of protein complexes and other molecules that transfer electrons from electron donors to electron acceptors via redox reactions (both reduction and oxidation occurring simultaneously) and couples this electron transfer with the transfer of protons (H+ ions) across a membrane.

Photosynthetic electron transport chain of the thylakoid membrane.

Depiction of ATP synthase, the site of oxidative phosphorylation to generate ATP.

The energy from the redox reactions creates an electrochemical proton gradient that drives the synthesis of adenosine triphosphate (ATP).

The energy released by reactions of oxygen and reduced compounds such as cytochrome c and (indirectly) NADH and FADH is used by the electron transport chain to pump protons into the intermembrane space, generating the electrochemical gradient over the inner mitochondrial membrane.

Adenine

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Nucleobase (a purine derivative).

Adenine on Crick and Watson's DNA molecular model, 1953. The picture is shown upside down compared to most modern drawings of adenine, such as those used in this article.

Its derivatives have a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD), flavin adenine dinucleotide (FAD) and Coenzyme A.

Pyruvate dehydrogenase complex

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Complex of three enzymes that converts pyruvate into acetyl-CoA by a process called pyruvate decarboxylation.

Pymol-generated image of E1 subunit of pyruvate dehydrogenase complex in E. Coli

Pymol-generated E3 subunit of pyruvate dehydrogenase complex in Pseudomonas putida

First, FAD oxidizes dihydrolipoate back to its lipoate resting state, producing FADH2.

Pyruvate dehydrogenase is inhibited when one or more of the three following ratios are increased: ATP/ADP, NADH/NAD+ and acetyl-CoA/CoA.

Beta oxidation

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Complete beta oxidation of linoleic acid (an unsaturated fatty acid).

In biochemistry and metabolism, beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH2, which are co-enzymes used in the electron transport chain.

1) Long-chain-fatty-acid—CoA ligase catalyzes the reaction between a fatty acid with ATP to give a fatty acyl adenylate, plus inorganic pyrophosphate, which then reacts with free coenzyme A to give a fatty acyl-CoA ester and AMP.

Ribose

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Simple sugar and carbohydrate with molecular formula C5H10O5 and the linear-form composition H−−(CHOH)4−H.

Pentose Phosphate Pathway: begins with -glucose and includes -ribose 5-phosphate as an intermediate

Metabolically-important species that include phosphorylated ribose include ADP, ATP, coenzyme A, and NADH.

For example, nicotinamide adenine dinucleotide (NAD), flavin adenine dinucleotide (FAD), and nicotinamide adenine dinucleotide phosphate (NADP) all contain the -ribofuranose moiety.

The succinate dehydrogenase complex showing several cofactors, including flavin, iron–sulfur centers, and heme.

Cofactor (biochemistry)

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Non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst .

A simple [Fe2S2] cluster containing two iron atoms and two sulfur atoms, coordinated by four protein cysteine residues.

The redox reactions of nicotinamide adenine dinucleotide.

For example, the multienzyme complex pyruvate dehydrogenase at the junction of glycolysis and the citric acid cycle requires five organic cofactors and one metal ion: loosely bound thiamine pyrophosphate (TPP), covalently bound lipoamide and flavin adenine dinucleotide (FAD), cosubstrates nicotinamide adenine dinucleotide (NAD+) and coenzyme A (CoA), and a metal ion (Mg2+).

Many contain the nucleotide adenosine monophosphate (AMP) as part of their structures, such as ATP, coenzyme A, FAD, and NAD+.