Alcohol oxidase

Several other biosensors have been developed usiag this oxygen-quenched fluorescence approach. Target species iaclude ethanol [64-17-5] hydrogen peroxide [7722-84-17, H2O2, lactate, and xanthine [69-89-6] C H4N402, usiag alcohol oxidase, catalase [9001-05-2] lactate oxidase, and xanthine oxidase, respectively. An additional technique for biocatalytic biosensors iavolves the firefly chemiluminescent reaction (17) ... 

On the base of alcohol oxidase and flavocytochrome b, the enzymatic kits for selective assay of ethanol, methanol, formaldehyde and L-lactate were developed. 

NADH. Immobilized redox mediators, such as the phenoxazine Meldola Blue or phenothiazine compoimds, have been particularly useful for this purpose (20) (see also Figure 4-12). Such mediation should be useful for many other dehydrogenase-based biosensors. High sensitivity and speed are indicated from the flow-injection response of Figure 3-21. The challenges of NADH detection and the development of dehydrogenase biosensors have been reviewed (21). Alcohol biosensing can also be accomplished in the presence of alcohol oxidase, based on measurements of the liberated peroxide product. 

Fraaije MW, WJH van Berkel (1997) Catalytic mechanism of the oxidative demethylation of 4-(methoxymethyl)phenol by vanillyl-alcohol oxidase. Evidence for formation of a /7-quinone intermediate. /Sio/ Chem 272 18111-18116. 

Guillen F, AT Martinez, MJ Martinez (1992) Substrate specificity and properties of the aryl-alcohol oxidase from the ligninolytic fungus Pleurotus eryngii. Eur J Biochem 209 603-611. 

Muheim A, R Waldner, MSA Leisola, A Fiechter (1990) An extracellular aryl-alcohol oxidase from the vihite-rot ivmgm Bjerkandera adusta. Enzyme Microbiol Technol 12 204-209. 

Kumar, A.K. and Goswami, P. (2006) Functional characterization of alcohol oxidases from Aspergillus terreus MTCC 6324. Applied Microbiology and Biotechnology, 72, 906-911. 

Besides the standard vectors for constitutive and inducible expression of genes in P. pastoris, new expression vectors and promoters with new regulatory features allowing, for example, also methanol-free inducible high-level expression were discovered or developed by mutagenesis of the mostly used alcohol oxidase promoter Paoxi [87]. Thus, a new P. pastoris expression system became available, which is commercialized by the company VTU (AT). 

Ketoreductases catalyze the reversible reduction of ketones and oxidation of alcohols using cofactor NADH/NADPH as the reductant or NAD + /NADP+ as oxidant. Alcohol oxidases catalyze the oxidation of alcohols with dioxygen as the oxidant. Both categories of enzymes belong to the oxidoreductase family. In this chapter, the recent advances in the synthetic application of these two categories of enzymes are described. 

Aryl alcohol oxidase from the ligninolytic fungus Pleurotus eryngii had a strong preference for benzylic and allylic alcohols, showing activity on phenyl-substituted benzyl, cinnamyl, naphthyl and 2,4-hexadien-l-ol [103,104]. Another aryl alcohol oxidase, vanillyl alcohol oxidase (VAO) from the ascomycete Penicillium simplicissimum catalyzed the oxidation of vanillyl alcohol and the demethylation of 4-(methoxymethyl)phenol to vanillin and 4-hydro-xybenzaldehyde. In addition, VAO also catalyzed deamination of vanillyl amine to vanillin, and hydroxylation and dehydrogenation of 4-alkylphenols. For the oxidation of 4-alkylphenol, the ratio between the alcohol and alkene product depended on the length and bulkiness of the alkyl side-chain [105,106]. 4-Ethylphenol and 4-propylphenol, were mainly converted to (R)-l-(4 -hydroxyphenyl) alcohols, whereas medium-chain 4-alkylphenols such as 4-butylphenol were converted to l-(4 -hydroxyphenyl)alkenes. 

Secondary alcohol oxidases catalyze the oxidation of secondary alcohols to ketones using molecular oxygen as oxidant. A secondary alcohol oxidase from polyvinyl alcohol-degrading bacterium Pseudomonas vesicularis var. povalolyticus PH exhibited activity toward several... 

Compared with ketoreductases, the synthetic application of alcohol oxidases has been less explored. However, selective oxidation of primary alcohols to aldehydes is superior to the chemical methods in terms of conversion yields, selectivity, and environmental friendliness of reaction conditions. In addition, coupling of alcohol oxidase with other enzymes provides a tremendous opportunity to develop multi-enzyme processes for the production of complex molecules. Therefore, a growing impact of alcohol oxidases on synthetic organic chemistry is expected in the coming years. 

Weenen, H., Boog, R.L.G.M. and Apeldoorn, W. (1995) Aldehydes from alcohols using alcohol oxidases and dehydrogenases. Colloques - Institut National de la Recherche Agronomique, 75 (Bioflavour 95), 375-380. 

Dienys, G., Jarmalavicius, S., Budriene, S. et al. (2003) Alcohol oxidase from the yeast Pichia pastoris — a potential catalyst for organic synthesis. Journal of Molecular Catalysis B-Enzymatic, 21 (1-2), 47—49. 

Karra-Chaabouni, M., Pulvin, S., Meziani, A. et al. (2003) Biooxidation of n-hexanol by alcohol oxidase and catalase in biphasic and micellar systems without solvent. Biotechnology and Bioengineering, 81 (1), 27-32. 

Isobe, K. and Nishise, H. (1994) Enzymic production of glyoxal from ethylene glycol using alcohol oxidase from methanol yeast. Bioscience Biotechnology and Biochemistry, 58 (1), 170-173. 

Clark, D.S., Geresh, S. and DiCosimo, R. (1995) Enantioselective oxidation of 2-methyl-1-alkanols by alcohol oxidase from methylotrophic yeasts. Bioorganic Medicinal Chemistry Letters, 5 (13), 1383-1388. 

Siebum, A., van Wijk, A., Schoevaart, R. and Kieboom, T. (2006) Galactose oxidase and alcohol oxidase scope and limitations for the enzymatic synthesis of aldehydes. Journal of Molecular Catalysis B-Enzymatic, 41 (3-1), 141-145. 

Pezzotti, F. and Therisod, M. (2007) Enantioselective oxidation of thioanisole with an alcohol oxidase/ peroxidase bienzymatic system. Tetrahedron Asymmetry, 18 (6), 701-704. 

Varela, E., Guillen, F., Martinez, A.T. and Martinez, M.J. (2001) Expression of Pleurotus eryngii aryl-alcohol oxidase in Aspergillus nidulans purification and characterization of the recombinant enzyme. Biochimica et Biophysica Acta, Protein Structure and Molecular, Enzymology, 1546 (1), 107-113. 

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