Alcohol oxidase has been detected in several strains of yeast, such as Candida, Pichia, and Hansenula, that utilize methanol as a sole carbon and energy source. Some of these enzymes have been isolated and partially characterized. Alcohol oxidase plays a major role in the metabolism of methanol resulting in the formation of formaldehyde. Primarily localized in the peroxisome, alcohol oxidase has also been found in the cytoplasm. Monomers are synthesized in the cytosol and assembled into octomers in the peroxisome. Octomerization is thought to be chaperone mediated. Alcohol oxidase is of interest for the study of protein translocation into peroxisomes. It catalyzes the oxidation of an alcohol to an aldehyde and hydrogen peroxide.
Alcohol oxidase is used for qualitative and quantitative determination of methanol or ethanol (blood alcohol) by colorimetric procedures. Unlike present ADH based assays for ethanol in biological specimens, no labile cofactors or trapping agents are required and considerably less enzyme is used per assay. Quantitative determination of alcohol using an oxygen electrode (enzyme electrode) is also possible. With or without catalase, alcohol oxidase can be used to remove alcohol or scavenge oxygen. Using dilute methanol, sensitive samples can be sterilized through release of the products formaldehyde and hydrogen peroxide. The enzyme can also be used to generate H2O2 in radio-iodine labelling procedures.
Alcohol oxidase catalyzes the oxidation of short-chain, primary, aliphatic alcohols to their respective aldehydes. It has the highest affinity for methanol. Alcohol oxidase is involved in the metabolism of methanol, which is important for yeasts that utilize methanol as their sole energy source. Alcohol oxidase is primarily found in the peroxisome but may be present in the cytoplasm as well.
Specific Activity: ≥10 u/mg Protein
Key Applications: Colorimetric determination of blood alcohol
Application Areas: Molecular Biology
Product Type: Proteins, Enzymes & Peptides
Presentation: Reddish Brown Frozen Liquid
Format: Frozen Liquid
Formulation: Supplied in 30% Sucrose, 0.1 M Potassium Phosphate Buffer at pH 8.0.
pH: Optimum pH is 7.2 (optional working range is pH 5.5 to 9).(Lit.)
NOTES:
Inactivation and Stability: Freezing does not inactivate the enzyme. Compared to other oxidases, it is relatively resistant to p-chloromercuribenzoate, heavy metals and hydrogen peroxide. Hydrogen peroxide does not inactivate the enzyme at concentrations many times higher than those reported to inactivate previously-described yeast alcohol oxidases (Hansenula, Candida). The temperature optimum is 45°C. Reaction: Alcohol + O2 -------> Aldehyde + H2O2
Specificity: The enzyme is specific for short-chain, linear aliphatic alcohols and oxidizes the following substrates with a relative velocity rate: methanol = ethanol > n-propanol > n-butanol. It also catalyzes the oxidation of allyl and propargyl alcohol, methyl and ethyl mercaptan and fromaldehyde at slower rates. Branched chain alcohols, C2-aldehydes or higher, ketones and organic acids are not substrates. However, some of these reagents can give false positive responses due to trace contamination with alcohol. Oxygen is the only known hydrogen acceptor. At air saturation, the apparent KM for alcohol oxidase is 0.7 mM using methanol and 9 mM using ethanol as the substrate. In oxygen saturated solutions the KM values are higher. The turnover number is 20,000 sec-1.
Storage & Handling: Store at -20°C.