Flavin adenine dinucleotide and

Coemymes effecting transfer of hydrogen. These include the pyridine nucleotides, nicotinamide-adenine dinucleolide and nicotinamide-adenine dinucleolide phosphate the flavin nucleotides such as flavin-adenine dinucleotide and lipoic acid. 

Selected entries from Methods in Enzymology [vol, page(s)] Determination of FMN and FAD by fluorescence titration with apoflavodoxin, 66, 217 purification of flavin-adenine dinucleotide and coenzyme A on p-acetoxymercurianiline-agarose, 66, 221 a convenient biosynthetic method for the preparation of radioactive flavin nucleotides using Clostridium kluyveri, 66, 227 isolation, chemical synthesis, and properties of roseoflavin, 66, 235 isolation, synthesis, and properties of 8-hydroxyflavins, 66, 241 structure, properties and determination of covalently bound flavins, 66, 253 a two-step chemical synthesis of lumiflavin, 66, 265 syntheses of 5-deazaflavins, 66, 267 preparation, characterization, and coenzymic properties of 5-carba-5-deaza and 1-... 

Ochoa reported that malic enzyme from L. plantarum was NAD and not NADP specific. The malic enzyme of cauliflower bud mitochondria (31) is NAD and NADP specific, with NAD being the preferred cofactor. Both the malo-lactic activity and NADH producing activity of the Leuconostoc oenos system (6,7, 8) was strictly NAD specific. Nicotinamide-adenine dinucleotide phosphate, flavin adenine dinucleotide, and flavin mononucleotide could not substitute in either of these activities. 

Flavin adenine diphosphate (FAD, flavin adenine dinucleotide) and riboflavin 5 -monophosphate (FMN, flavin mononucleotide), whose structures are shown in Fig. 15-7, are perhaps the most versatile of all... 

Sevrioukova, I., Truan, G., and Peterson, J. A. 1996. The flavoprotein domain of P450BM-3 Expression, purification, and properties of the flavin adenine dinucleotide and flavin mononucleotide-binding subdomains. Biochemistry, 35,7528-7535. 

Vitamin B complex is the collective term for a number of water-soluble vitamins found particularly in dairy products, cereals and liver.Vitamin B (thiamine) is used by mouth for dietary supplement purposes and by injection in emergency treatment of Wernicke-Korsakoff syndrome. Vitamin B2 (riboflavin) is a constituent of the coenzyme FAD (flavine adenine dinucleotide) and FMN (flavine mononucleotide) and is therefore important in cellular respiration. Vitamin Be (pyridoxine) is a coenzyme for decarboxylases and transamination, and is concerned with many metabolic processes. Overdose causes peripheral neuropathy. It may be used medically for vomiting and radiation sickness and for premenstrual tension. Pyridoxine has a negative interaction with the therapeutic use of levodopa in parkinsonism by enhancing levodopa decarboxylation to dopamine in the periphery, which does not then reach the brain. The antitubercular drug isoniazid interferes with pyridoxine, and causes a deficiency leading to peripheral neuritis that may need to be corrected with dietary supplements. Vitamin B ... 

If the two wavelengths. A,- and Aj, and the two chromophores are very close, however, the denominator of these two terms, R and Rjt, becomes quite small and these terms can dominate in the summations for Rj and Rj. This has been demonstrated in a number of dinucleotide prosthetic groups of enzymes, such as flavin-adenine dinucleotide and nicotinamide-adenine dinucleotide. An example is given below for the adenine and nicotinate chromophores. 

The model system that was used to demonstrate the reciprocal relations was adenosine-5 -mononicotinate, which is given in the stacked or interacted conformation in Fig. 6. The temperature effect for this molecule as seen in the circular dichroism spectra is given in Fig. 7, where the reciprocal relations are beautifully apparent. This approach has been used to identify stacked conformations for flavin-adenine dinucleotide and for the oxidized and reduced forms of a- and /3-nicotinamide-adenine dinucleotide. ... 

Flavin Adenine Dinucleotide and Flavin Mononucleotide Vitamin B2... 

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. 

Several other analytical procedures are available for enzyme activity determination. Fluorescence, this is the ability of certain molecules to absorb light at a certain wavelength and emit it at another, is a property than can be used for enzymatic analysis. NADH, but also FAD (flavin adenine dinucleotide) and FMN (flavin mononucleotide) have this property that can be used for those enzyme requiring that molecules as coenzymes (Eschenbrenner et al. 1995). This method shares some of the good properties of spectrophotometry and can also be integrated into an HPLC system, but it is less flexible and the equipment not so common in a standard research laboratory. 

Description. Riboflavin is a water-soluble B-complex vitamin, also known as vitamin B2. In the body, riboflavin functions in the mitochondrial electron transport systan as the coenzymes, flavin adenine dinucleotide and flavin mononucleotide. ... 

Microsomal cytochromes P450 are membrane-bound. They accept electrons from a microsomal NADPH-cytochrome reductase, containing flavin adenine dinucleotide and flavin mononucleotide. All cytochromes P450 metaboUsing drugs and xeno-biotica isolated so far belong to this class. 

Xanthine oxidase can reduce nitrate to nitrite (Westerfield et al. 1959, Fridovich and Handler 1962). Xanthine oxidase and dissimilatory nitrate reductase share structural similarities. Both are molybdoenzymes and contain flavin adenine dinucleotide and Fe/S clusters (McCord 1985, Mitchell 1986, Payne et al. 1997). Zhang et al. (1998) reported that both purified bovine buttermilk xanthine oxidase and xanthine oxidase-containing inflamed human synovial tissue can generate NO by reducing nitrite in the presence of NADH. This nitrite reductase activity of xanthine oxidase may act as a supplement to the activity of nitric oxide synthase (NOS) to redistribute blood flow to ischaemic tissues when NOS activity is absent. 

Other molecules that can accept two electrons are flavins FAD (flavin adenine dinucleotide) and FMN (flavin mononucleotide). The former coenzyme is formed by adenine-ribose-diphosphate, followed by a linear sugar-type molecule and, finally, the aromatic ring (isoalloxazine) of Figure 11.7. FMN is missing adenine, ribose, and one of the phosphates at the beginning of the chain. Flavins are prosthetic groups in fiavoproteins involved in the ET chain of Complex 11. 

Scheme 14.9. A cartoon representation using a one-electron pathway (although a similar pathway using two electrons might be written) to convert dihydroorotidme to orotidine with reduced flavin adenine dinucleotide and oxygen. The other product is hydrogen peroxide (or its equivalent).

Both flavin adenine dinucleotide and the closely related flavin mononucleotide (FMN) contain riboflavin (page 163) as an essential component. Riboflavin, a member of the vitamin B complex, is a derivative of isoalloxazine to which is attached ribitol, a pentahydroxy alcohol related to ribose. FMN consists of riboflavin esterified with phosphate on C-5 of the ribitol. 

I Chibata, T Tosa, Y Matuo. Purification of flavin-adenine dinucleotide and coenzyme A on p-acetomercurianiline-agarose. Methods Enzymol 66 221-226, 1980. 

Flavin adenine dinucleotide and its reduced form Thiamine pyrophosphate Coenzyme A... 

Goran, J. M., Mantilla, S. M., and Stevenson, K. J. 2013. Influence of surface adsorption on the interfacial electron transfer of flavin adenine dinucleotide and glucose oxidase at carbon nanotube and nitrogen-doped carbon nanotube electrodes. Anal. Chem. 85 1571-1581. 

One important subgroup of the lyases are the decarboxylases. The decarboxylation of amino acids is assisted by pyridoxal phosphate as a prosthetic group, whereas in the decarboxylation of pyruvate to acetaldehyde, thiamine pyrophosphate (TPP) plays that role. Oxidative decarboxylation, lastly, depends on the cooperation of no fewer than five cofactors thiamine pyrophosphate, lipoic acid, coenzyme A, flavin-adenine dinucleotide, and nicotinamide-adenine dinucleotide. 

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