Examples of electron donor in the following topics:
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- Sulfate reduction requires the use of electron donors, such as the carbon compounds lactate and pyruvate (organotrophic reducers), or hydrogen gas (lithotrophic reducers).
- Some unusual autotrophic sulfate-reducing bacteria, such as Desulfotignum phosphitoxidans, can use phosphite (HPO3-) as an electron donor.
- Others, such as certain Desulfovibrio species, are capable of sulfur disproportionation (splitting one compound into an electron donor and an electron acceptor) using elemental sulfur (S0), sulfite (SO3−2), and thiosulfate (S2O32-) to produce both hydrogen sulfide (H2S) and sulfate (SO2−).
- Acetogenesis is a type of microbial metabolism that uses hydrogen (H2) as an electron donor and carbon dioxide (CO2) as an electron acceptor to produce acetate, the same electron donors and acceptors used in methanogenesis.
- Describe various types of electron acceptors and donors including: nitrate, sulfate, hydrgoen, carbon dioxide and ferric iron
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- In prokaryotes (bacteria and archaea there are several different electron donors and several different electron acceptors.
- In the present day biosphere, the most common electron donors are organic molecules.
- Inorganic electron donors include hydrogen, carbon monoxide, ammonia, nitrite, sulfur, sulfide, and ferrous iron.
- The use of inorganic electron donors as an energy source is of particular interest in the study of evolution.
- NADH is the electron donor and O2 is the electron acceptor.
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- Chemolithotrophs use electron donors oxidized in the cell, and channel electrons into respiratory chains, producing ATP.
- Chemotrophs are organisms that obtain energy through the oxidation of electron donors in their environments.
- In chemolithotrophs, the compounds - the electron donors - are oxidized in the cell, and the electrons are channeled into respiratory chains, ultimately producing ATP.
- The electron acceptor can be oxygen (in aerobic bacteria), but a variety of other electron acceptors, organic and inorganic, are also used by various species.
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- Carbon fixation is a redox reaction, so photosynthesis needs to supply both a source of energy to drive this process, and the electrons needed to convert carbon dioxide into a carbohydrate, which is a reduction reaction.
- However, the two processes take place through a different sequence of chemical reactions and in different cellular compartments.The general equation for photosynthesis is therefore:2n CO2 + 2n DH2 + photons → 2(CH2O)n + 2n DOCarbon dioxide + electron donor + light energy → carbohydrate + oxidized electron donor.In oxygenic photosynthesis water is the electron donor and, since its hydrolysis releases oxygen, the equation for this process is:2n CO2 + 4n H2O + photons → 2(CH2O)n + 2n O2 + 2n H2Ocarbon dioxide + water + light energy → carbohydrate + oxygen + waterOften 2n water molecules are cancelled on both sides, yielding:2n CO2 + 2n H2O + photons → 2(CH2O)n + 2n O2carbon dioxide + water + light energy → carbohydrate + oxygen
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- In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule to another.
- In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another the oxidant, also called the electron acceptor.
- In this example, A is the reductant (electron donor) and B is the oxidant (electron acceptor).
- In this reaction, NAD+ is the oxidant (electron acceptor) and glyceraldehyde-3-phosphate is the reductant (electron donor).
- Oxidoreductases can be further classified into 22 subclasses: EC 1.1 includes oxidoreductases that act on the CH-OH group of donors (alcohol oxidoreductases); EC 1.2 includes oxidoreductases that act on the aldehyde or oxo group of donors; EC 1.3 includes oxidoreductases that act on the CH-CH group of donors (CH-CH oxidoreductases); EC 1.4 includes oxidoreductases that act on the CH-NH2 group of donors (Amino acid oxidoreductases, Monoamine oxidase); EC 1.5 includes oxidoreductases that act on CH-NH group of donors; EC 1.6 includes oxidoreductases that act on NADH or NADPH; EC 1.7 includes oxidoreductases that act on other nitrogenous compounds as donors; EC 1.8 includes oxidoreductases that act on a sulfur group of donors; EC 1.9 includes oxidoreductases that act on a heme group of donors; EC 1.10 includes oxidoreductases that act on diphenols and related substances as donors; EC 1.11 includes oxidoreductases that act on peroxide as an acceptor (peroxidases); EC 1.12 includes oxidoreductases that act on hydrogen as donors; EC 1.13 includes oxidoreductases that act on single donors with incorporation of molecular oxygen (oxygenases); EC 1.14 includes oxidoreductases that act on paired donors with incorporation of molecular oxygen; EC 1.15 includes oxidoreductases that act on superoxide radicals as acceptors; EC 1.16 includes oxidoreductases that oxidize metal ions; EC 1.17 includes oxidoreductases that act on CH or CH2 groups; EC 1.18 includes oxidoreductases that act on iron-sulfur proteins as donors; EC 1.19 includes oxidoreductases that act on reduced flavodoxin as a donor; EC 1.20 includes oxidoreductases that act on phosphorus or arsenic in donors; EC 1.21 includes oxidoreductases that act on X-H and Y-H to form an X-Y bond; and EC 1.97 includes other oxidoreductases.
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- Sulfate reduction is a type of anaerobic respiration that utilizes sulfate as a terminal electron acceptor in the electron transport chain.
- Sulfate reduction is a type of anaerobic respiration that utilizes sulfate as a terminal electron acceptor in the electron transport chain.
- Many sulfate reducers are organotrophic, using carbon compounds, such as lactate and pyruvate (among many others) as electron donors, while others are lithotrophic, and use hydrogen gas (H2) as an electron donor.
- Some unusual autotrophic sulfate-reducing bacteria (e.g., Desulfotignum phosphitoxidans) can use phosphite (HPO3-) as an electron donor, whereas others (e.g., Desulfovibrio sulfodismutans, Desulfocapsa thiozymogenes, and Desulfocapsa sulfoexigens) are capable of sulfur disproportionation (splitting one compound into two different compounds, in this case an electron donor and an electron acceptor) using elemental sulfur (S0), sulfite (SO32−), and thiosulfate (S2O32−) to produce both hydrogen sulfide (H2S) and sulfate (SO42−).
- In organisms that use carbon compounds as electron donors, the ATP consumed is accounted for by fermentation of the carbon substrate.
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- Lewis bases are electron-pair donors, whereas Lewis acids are electron-pair acceptors.
- A Lewis acid is defined as an electron-pair acceptor, whereas a Lewis base is an electron-pair donor.
- Under this definition, we need not define an acid as a compound that is capable of donating a proton, because under the Lewis definition, H+ itself is the Lewis acid; this is because, with no electrons, H+ can accept an electron pair.
- A Lewis base, therefore, is any species that donates a pair of electrons to a Lewis acid.
- The "neutralization" reaction is one in which a covalent bond forms between an electron-rich species (the Lewis base) and an electron-poor species (the Lewis acid).
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- The electron affinity (Eea) of a neutral atom or molecule is defined as the amount of energy released when an electron is added to it to form a negative ion, as demonstrated by the following equation:
- Mulliken used a list of electron affinities to develop an electronegativity scale for atoms by finding the average of the electron affinity and ionization potential.
- A molecule or atom that has a more positive electron affinity value is often called an electron acceptor; one with a less positive electron affinity is called an electron donor.
- To use electron affinities properly, it is essential to keep track of the sign.
- Electron affinity follows the trend of electronegativity: fluorine (F) has a higher electron affinity than oxygen (O), and so on.
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- The atom within a ligand that is bonded to the central atom or ion is called the donor atom.
- A typical complex is bound to several donor atoms, which can be same or different elements.
- The central atoms or ion and the donor atoms comprise the first coordination sphere.
- There are two different mechanisms of electron transfer redox reactions: inner sphere or outer sphere electron transfer.
- The EDTA molecule has six different donor atoms that form the complex.
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- The energy of these bands is between the energy of the ground state and the free electron energy (the energy required for an electron to escape entirely from the material).
- In semiconductors, only a few electrons exist in the conduction band just above the valence band, and an insulator has almost no free electrons.
- For example, in III-V semiconductors such as gallium arsenide, silicon can be a donor when it substitutes for gallium or an acceptor when it replaces arsenic.
- Some donors have fewer valence electrons than the host, such as alkali metals, which are donors in most solids.
- This allows for easier electron flow.