Dehydrogenases formaldehyde dehydrogenase

Novel glycerol and formaldehyde selective sensors based on pEI-Sensitive Field Effect Transistors as transducers and Glycerol Dehydrogenase and Formaldehyde Dehydrogenase as biorecognition elements have been developed. The main analytical parameters of the sensors have been investigated and will be discussed. 

Liver alcohol dehydrogenase (ADH) is relatively nonspecific and will oxidize ethanol or other alcohols, including methanol. Methanol oxidation yields formaldehyde, which is quite toxic, causing, among other things, blindness. Mistaking it for the cheap... 

Conversion of methanol into formaldehyde by methanol dehydrogenase. A complex array of genes is involved in this oxidation and the dehydrogenase contains pyrroloquinoline quinone (PQQ) as a cofactor (references in Ramamoorthi and Lidstrom 1995). Details of its function must, however, differ from that of methylamine dehydrogenase that also contains a quinoprotein—tryptophan tryptophylquinone (TTQ). 

MARTINEZ, M.C., ACHKOR, H., PERSSON, B., FERNANDEZ, M.R., SHAFQAT, J., FARRES, J., JORNVALL, H., PARES, X., Arabidopsis formaldehyde dehydrogenase. Molecular properties of plant class III alcohol dehydrogenase provide further insights into the origins, structure and function of plant class P and liver class I alcohol dehydrogenases, Eur. J. Biochem., 1996,241, 849-857. 

BARBER, R.D., DONOHUE, T.J., Function of a glutathione-dependent formaldehyde dehydrogenase in Rhodobacter sphaeroides formaldehyde oxidation and assimilation, Biochemistry, 1998, 37, 530-537. 

The same authors proposed a complex system for the electrochemically driven enzymatic reduction of carbon dioxide to form methanol. In this case, methyl viologen or the cofactor PQQ were used as mediators for the electroenzymatic reduction of carbon dioxide to formic acid catalyzed by formate dehydrogenase followed by the electrochemically driven enzymatic reduction of formate to methanol catalyzed by a PQQ-dependent alcohol dehydrogenase. With methyl viologen as mediator, the reaction goes through the intermediate formation of formaldehyde while with PQQ, methanol is formed directly [77],... 

NAD(P)+ as Anode Mediator. A majority of redox enzymes require the cation nicotinamide adenine dinucleotide, possibly phosphorylated (NAD(P)+) as a cofactor. Of the oxidoreductases listed in Enzyme Nomenclature, over 60% have NAD(P)+ as a reactant or product.For example, methanol can be oxidized to form formaldehyde by methanol dehydrogenase (MDH, EC 1.1.1.244) according to... 

This release of formaldehyde can also be quantified by using formaldehyde dehydrogenase, as described above. An alternative way to determine demethylase activity by measuring the amounts of released formaldehyde is the use of the Nash reaction [68, 69]. This method is based on the formation of the colored 3,5-diacetyl-1,4-dihydropyridine by condensation of formaldehyde and acetylacetone in the... 

This enzyme [EC 1.2.1.46] converts formaldehyde and NAD and water into formate and NADH. A similarly named enzyme [EC 1.2.1.1] converts formaldehyde and glutathione in the presence of NAD into -formylgluta-thione plus NADH. See also Aldehyde Dehydrogenase... 

Methanol or methyl alcohol can become an alcoholic s main source of alcohol because it is cheaper. Methanol is frequently used as an additive for industrial ethanol to circumvent taxes. Methanol may be purposely adulterated to make it less palatable, but it is used nevertheless Methanol ingestion can be fatal due to its CNS depressant effects. In addition it is toxic because it is a substrate for alcohol dehydrogenase forming formic acid and formaldehyde which... 

There are some methods that are specific to HCHO. For example, the Hantzsch reaction of HCHO, collected with a diffusion scrubber, with ammonium acetate, acetic acid, and acetylacetone to form diacetyldihydrolutidine, which is measured using its fluorescence at 470 nm, has been applied to air measurements (Dasgupta et al., 1988, 1990 Kleindienst et al., 1988a,b Lawson et al., 1990 Khare et al., 1997). Reaction with 1,3-cyclohexanedione and ammonium acetate to form a dihydropyridine derivative that is measured by fluorescence has been used in conjunction with a diffusion scrubber (Fan and Dasgupta, 1994). Enzymatic methods have been used in which formaldehyde dehydrogenase catalyzes the oxidation of HCHO to HCOOH in the presence of -nicotinamide adenine dinucleotide, NAD+, which is reduced to NADH. The latter is measured by fluorescence at 450 nm (Lazrus et al., 1988 Ho and Richards, 1990). 

Methyl alcohol is only used to denature ethyl alcohol in 5 percent concentration. It is metabolised to formaldehyde and formic acid by alcohol and aldehyde dehydrogenases. Its absorption and distribution are similar to ethyl alcohol. 

Methanol is converted to the toxic metabolites formaldehyde and formate by alcohol dehydrogenase and aldehyde dehydrogenase. By inhibiting alcohol dehydrogenase, ethanol and fomepizole reduce the formation of toxic metabolites. 

Methyl alcohol is poisonous and is commonly used to denature ethyl alcohol. Methanol poisoning results from ingestion, inhalation of methanol vapors, or absorption through the skin. Methanol is transformed in the body to formaldehyde (H2CO) by the enzyme alcohol dehydrogenase. The formaldehyde is then metabolized to formic acid (HCOOH)... 

As well as these major application fields, biosensors and analytical techniques should also benefit from the technology. Some examples have already been described. The detection of formaldehyde by a formaldehyde dehydrogenase coated onto a piezoelectric crystal has been performed at the ppm level. Detection of pesticides and organophosphorus compounds at the ppb level has been rendered... 

TA medical therapy based on competition at the active site is used to treat patients who have ingested methanol, a solvent found in gas-line antifreeze. The liver enzyme alcohol dehydrogenase converts methanol to formaldehyde, which is damaging to many tissues. Blindness is a common result of methanol ingestion, because... 

In bacteria, which lack formate dehydrogenase, formaldehyde can be oxidized to C02 to provide energy beginning with the reactions of Eq. 17-51. The resulting fructose 6-P is isomerized to glucose 6-P, which is then dehydrogenated via Eq. 17-12 to form C02 and the regenerating substrate ribulose 5-phosphate. 

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