Flavin adenine dinucleotide oxidase with

Rgure 2 Structural formulae of two enzyme cofactors (A) nicotinamide adenine dinucleotide (NAD) and (B) flavin adenine dinucleotide (FAD) with the corresponding redox transformations in dehydrogenases and oxidases catalyzed reaction, respectively. NAD is a soluble cofactor and it has to be added to the reaction mixture. As shown in Figure 1, FAD is bound to the flavoprotein. 

Glucose oxidase (GOD) is a typical flavin enzyme with flavin adenine dinucleotide (FAD) as redox prosthetic group. Its biological function is to catalyze glucose to form gluconolaction, while the enzyme itself is turned from GOD(FAD) to GOD(FADH2). GOD was used to prepare biosensors in extensive fields. Many materials that can be used to immobilize other proteins can be suitable for GOD. GOD adsorbed on CdS nanoparticles maintained its bioactivity and structure, and could electrocatalyze... 

Figure 9.6 Sequence of electron carriers in the electron transfer chain. The positions of entry into the chain from metabolism of glucose, glutamine, fatty acyl-CoA, glycerol 3-phosphate and others that are oxidised by the Krebs cycle are shown. The chain is usually considered to start with NADH and finish with cytochrome oxidase. FMN is flavin mononucleotide FAD is flavin adenine dinucleotide.

Au NPs (1.2 nm) that include a single /V-hydroxysuccinimide-active ester functionality were modified with 2-amino-ethyl-flavin adenine dinucleotide, (5), and apo-glucose oxidase was reconstituted on the FAD cofactor units to yield the Au NP-GOx hybrid (Fig. 12.6a). The resulting hybrids were linked to the Au surface by different dithiol bridging units (8), (9), and (10). The resulting NP-functionalized glucose oxidase, GOx, exhibited electrical contact with the electrode surface, and the Au NPs... 

Conditions for cytosolic incubations depend on the aim of the assay e.g. to cover specific enzymatic activity present in the cytosol. For this purpose it is essential to fortify the incubation medium with the specific cofactor for the reaction-if needed (Ekins 1999). (J> -Nicotinamide adenine dinucleotide (NAD) is needed for alcohol and aldehyde dehydrogenases, flavin adenine dinucleotide (FAD) for polyamine oxidase, P-nicotinamide adenine dinucleotide phosphate (NADPH) for Dihydropyrimidine dehydrogenase. Phase II reactions depend on PAPS (sulfotransferases,... 

Aldehyde oxidase purified from maize coleoptiles is a multicomponent enzyme that contains a molybdenum cofactor, nonheme iron, and flavin adenine dinucleotide (FAD) as prosthetic groups.111 When substrate specificity of the aldehyde oxidase was tested, good activity was detected with IAAld, indole-3-aldehyde, and benzaldehyde among others. The addition of NADP and NADPH did not change the activity. In contrast, in maize endosperm, tryptophan-dependent IAA biosynthesis was dependent on an NADP/NADPH redox system, which may mean that the two tissues of maize are utilizing different pathways or different redox systems for IAA biosynthesis.112... 

In 1998, we reported the real-time observation of enzymatic turnovers of a single-molecule cholesterol oxidase, a flavoenz3mie that catalyzes oxidation of cholesterol by oxygen [15] (Fig. 22.lA). The active site of the enz3une, flavin adenine dinucleotide (FAD), (Fig. 22.IB), is naturally fluorescent in its oxidized form but not in its reduced form. With excess amounts of cholesterol... 

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