Flavin adenine dinucleotide synthetase

Mack, M., van Loon, A.P.G.M., and Hohmann, H.-P. (1998) Regulation of riboflavin biosynthesis in Bacillus suhtilis is affected by the activity of the flavokinase/flavin adenine dinucleotide synthetase encoded by ribC. 

Enzyme purification was the first application of bioaffinity chromatography [23] and remains an important use of this technique. In this type of separation, ligands, such as enzyme inhibitors, coenzymes, or cofactors, are used to purify and separate enzymes [25]. For instance, in 1968 and the first report of "modem" affinity chromatography, Cuatrecasas, Wilchek, and Anfinsen employed specific enzyme inhibitors to selectively isolate enzymes [1,4]. A more recent example was the use of a support containing flavin mononucleotides for the purification of flavin adenine dinucleotide synthetase [26]. Other examples have included the use of mono-, di-, and triphosphate nucleotides for the purification of kinases and the use of nicotinamide adenine dinucleotide for the isolation of dehydrogenases [26,27]. 

F26BP, fructose-2,6-bisphosphate FA, fatty acid FAD, fatty acid desaturase FADH2/FAD, reduced/oxidized flavin adenine dinucleotide F -ATPase, ATP synthetase F complex FGF, fibroblast growth factor FGF-RTK, fibroblast growth factor receptor tyrosine kinase Fmet, formylmethionine FMNH2/FMN, reduced/oxidized flavin mononucleotide... 

Methylene-Tetrahydrofolate Reductase The reduction of methylene-tetrahydrofolate to methyl-tetrahydrofolate, shown in Figure 10.7, is catalyzed hy methylene-tetrahydrofolate reductase, a flavin adenine dinucleotide-dependent enzyme during the reaction, the pteridine ring of the substrate is oxidized to dihydrofolate, then reduced to tetrahydrofolate by the flavin, which is reduced by nicotinamide adenine dinucleotide phosphate (NADPH Matthews and Daubner, 1982). The reaction is irreversible under physiological conditions, and methyl-tetrahydrofolate - which is the main form of folate taken up into tissues (Section 10.2.2) - can only be utilized after demethylation catalyzed by methionine synthetase (Section 10.3.4). 

Ann O Rexia has been malnourished for some time, and has developed subclinical deficiencies of many vitamins, including riboflavin. The coenzymes FAD (flavin adenine dinucleotide) and FMN (flavin mononucleotide) are synthesized from the vitamin riboflavin. Riboflavin is actively transported into cells, where the enzyme flavokinase adds a phosphate to form FMN. FAD synthetase then adds AMP to form FAD. FAD is the major coenzyme in tissues and is generally found tightly bound to proteins, with about 10% being covalently bound. Its turnover in the body is very slow, and people can live for long periods on low intakes without displaying any signs of a riboflavin deficiency. 

Other - Farnesylpyrophosphate synthetase has been used in asymmetric synthesis of isoprenoids. Potato acid phosphatase has been applied to mild hydrolysis of polyprenyl pyrophosphates. Sulfatase-catalyzed hydrolysis of /9-napthol sulfate has been used to separate a- and 8-napthols. NAD and flavin adenine dinucleotide have been made by enzymic coupling reactions. 

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