CHOLINE OXIDASE FROM ARTHROBACTER SP.

Application

Choline oxidase from Sigma has been used in the enzymatic determination of choline in milk using a flow injection analysis (FIA) system with potentiometric detection.†

Biochem/physiol Actions

Choline oxidase from Arthrobacter sp. is a flavoprotein, which is a member of the GMC-oxidoreductase family. The enzyme catalyzes the four-electron-oxidation of choline to glycine betaine via the intermediate betaine aldehyde, in two sequential FAD-dependent reaction steps. The enzyme is useful for enzymatic determination of phosphatidylcholine by coupling with phospholipase D or determination of sphingomyelin by coupling with sphingomyelinase and for cholinesterase activity assays.Choline oxidase, isolated from the soil bacterium Arthrobacter globiformis helps to transform choline to glycinebetaine (N-trimethylglycine).

General description

The codA gene encodes the choline oxidase enzyme.

Preparation Note

It is recommended to reconstitute choline oxidase in phosphate buffer at pH 7.5 supplemented with 10mM EDTA. Reconstituted material can be stored at 2-8 °C for at least 2 weeks.

Unit Definition

One unit will form 1 µmole of H₂O₂ with oxidation of 1 µmole of choline to betaine aldehyde per min at pH 8.0 at 37 °C. Note: During the conversion of choline to betaine by choline oxidase, 2 µmoles of H₂O₂ are produced for every µmole of choline.