Search results
Results from the WOW.Com Content Network
In biochemistry, denaturation is a process in which proteins or nucleic acids lose folded structure present in their native state due to various factors, including application of some external stress or compound, such as a strong acid or base, a concentrated inorganic salt, an organic solvent (e.g., alcohol or chloroform), agitation and radiation, or heat. [3]
Binding of ferredoxin to the enzyme causes the formation of a hydrogen bond between a glutamate residue (E312) and a serine residue (S96) in the active site. [4] The glutamate residue is highly conserved because it both stabilizes the semiquinone form of FAD and is a proton donor/acceptor in the reaction. [ 5 ]
For example, an enzyme that catalyzed this reaction would be an oxidoreductase: A – + B → A + B – In this example, A is the reductant (electron donor) and B is the oxidant (electron acceptor). In biochemical reactions, the redox reactions are sometimes more difficult to see, such as this reaction from glycolysis:
Oxidoreductases, enzymes that catalyze oxidation-reduction reactions, constitute Class EC 1 of the IUBMB classification of enzyme-catalyzed reactions. [2] Any of these may be called dehydrogenases, especially those in which NAD + is the electron acceptor (oxidant), but reductase is also used when the physiological emphasis on reduction of the substrate, and oxidase is used only when O 2 is the ...
Ribonucleotide reductase (RNR), also known as ribonucleoside diphosphate reductase, is an enzyme that catalyzes the formation of deoxyribonucleotides from ribonucleotides. [1] [2] It catalyzes this formation by removing the 2'-hydroxyl group of the ribose ring of nucleoside diphosphates (or triphosphates depending on the class of RNR).
In the less extensive technique of equilibrium unfolding, the fractions of folded and unfolded molecules (denoted as and , respectively) are measured as the solution conditions are gradually changed from those favoring the native state to those favoring the unfolded state, e.g., by adding a denaturant such as guanidinium hydrochloride or urea.
The active site of these enzymes is a molybdenum ion that is bound to the four thiolate functional groups of two pterin molecules. The coordination sphere of the molybdenum ion is completed by one amino-acid side chain and oxygen and/or sulfur ligands. In Nap, the molybdenum is covalently attached to the protein by a cysteine side chain, and an ...
Unlike denaturing methods, native gel electrophoresis does not use a charged denaturing agent. The molecules being separated (usually proteins or nucleic acids ) therefore differ not only in molecular mass and intrinsic charge, but also the cross-sectional area, and thus experience different electrophoretic forces dependent on the shape of the ...