Product Name

Choline Oxidase from Arthrobacter globiformis

Synonym

Choline: oxygen 1-oxidoreductase

Assay

8-20 units/mg solid

CAS Number

9028-67-5

MDL number

MFCD00130787

Suitability

BioReagent

l Physical and Chemical Information

Appearance

lyophilized powder

l Biological Information

Biochem/Physiol Actions

Choline oxidase catalyzes the four-electron oxidation of choline to glycine-betaine, with betaine-aldehyde as intermediate and molecular oxygen as primary electron acceptor. The enzyme can also accept betaine-aldehyde as a substrate. This allows the investigation of the reaction mechanism for the conversion of choline to the aldehyde intermediate and of betaine-aldehyde to glycine-betaine. The enzyme is a flavoprotein with a molecular weight of approximately 83,000 Da according to gel filtration or approximately 71,000 Da according to SDS gel electrophoresis. The optimum pH is found to be around pH 7.5 and the isoelectric point (pI) around pH 4.5.

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.

Preparation Note

Solutions of choline oxidase may be prepared in 10 mM Trizma^®-HCl, pH 8.0, with 2.0 mM EDTA and 134 mM KCl.9 Choline oxidase solutions may also be prepared in 200mM Trizma^® -HCl, pH 8.0.6 Another publication cites preparation of 2 mg/mL stock solutions of choline oxidase in carbonate buffer, pH 9.0.

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.

l Storage

Storage temp.

-20℃

l Precautions and Disclaimer

This product is for R&D use only, not for drug, household, or other uses.

l References

1. http://www.drugbank.ca

2. https://ncit.nci.nih.gov

3. https://www.ncbi.nlm.nih.gov