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Cyanocobalamin is a form of vitamin B 12 used to treat and prevent vitamin B 12 deficiency except in the presence of cyanide toxicity. [7] [8] [2] The deficiency may occur in pernicious anemia, following surgical removal of the stomach, with fish tapeworm, or due to bowel cancer.
The structure of vitamin B 12 was the first low-molecular weight natural product determined by x-ray analysis rather than by chemical degradation. Thus, while the structure of this novel type of complex biomolecule was established, its chemistry remained essentially unknown; exploration of this chemistry became one of the tasks of the vitamin's chemical synthesis.
Cyanocobalamin is a manufactured form of B 12. Bacterial fermentation creates AdoB 12 and MeB 12, which are converted to cyanocobalamin by the addition of potassium cyanide in the presence of sodium nitrite and heat. Once consumed, cyanocobalamin is converted to the biologically active AdoB 12 and MeB 12. [citation needed] The two bioactive ...
In enzymology, a cyanocobalamin reductase (cyanide-eliminating) (EC 1.16.1.6) is an enzyme that catalyzes the chemical reaction cob(I)alamin + cyanide + NADP + ⇌ {\displaystyle \rightleftharpoons } cyanocob(III)alamin + NADPH + H +
Vitamin B 12 deficiency; Other names: Hypocobalaminemia, cobalamin deficiency: Image of the cervical spinal cord in vitamin B 12 deficiency showing subacute combined degeneration. . (A) The midsagittal T2 weighted image shows linear hyperintensity in the posterior portion of the cervical tract of the spinal cord (black arrow
Vitamin B 12 (cyanocobalamin) Corrinoids are a group of compounds based on the skeleton of corrin, a cyclic system containing four pyrrole rings similar to porphyrins. [2] These include compounds based on octadehydrocorrin, which has the trivial name corrole. [3] The cobalamins (vitamin B 12) are the best known members of the group.
Hydroxocobalamin has a higher affinity to the TC II transport protein than cyanocobalamin, or adenosylcobalamin. From a biochemical point of view, two essential enzymatic reactions require vitamin B 12 (cobalamin). [21] [22] Intracellular vitamin B 12 is maintained in two active coenzymes, methylcobalamin and adenosylcobalamin.
Hydroxocobalamin, a form (or vitamer) of vitamin B 12 made by bacteria, and sometimes denoted vitamin B 12a, is used to bind cyanide to form the harmless cyanocobalamin form of vitamin B 12. 4-Dimethylaminophenol: 4-Dimethylaminophenol (4-DMAP) has been proposed [by whom?] in Germany as a more rapid antidote than nitrites with (reportedly ...