Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary extracted from

  • Quaye, O.; Nguyen, T.; Gannavaram, S.; Pennati, A.; Gadda, G.
    Rescuing of the hydride transfer reaction in the Glu312Asp variant of choline oxidase by a substrate analogue (2010), Arch. Biochem. Biophys., 499, 1-5.
    View publication on PubMed

Protein Variants

EC Number Protein Variants Comment Organism
1.1.3.17 E312D site-directed mutagenesis, the mutant enzyme shows a 260fold decrease in the rate constant for the hydride transfer reaction and did not transfer the hydride ion in a full quantum mechanical tunneling fashion. The overall turnover of the Glu312Asp enzyme at saturating concentrations of 3-hydroxypropyl-trimethylamine and oxygen is predominantly controlled by the hydride transfer reaction that results in the reduction of the enzyme-bound flavin. The kred value with 3-hydroxypropyl-trimethylamine is 20times higher than the value determined with choline as substrate for the Glu312Asp enzyme. The reductive half-reaction can be effectively, but not completely,rescued upon introducing on the substrate the methylenethat is missing from the side chain of residue 312 Arthrobacter globiformis

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
1.1.3.17 additional information
-
 additional information stopped-flow and steady-state kinetics, and sequential steady-state kinetic mechanism, overview Arthrobacter globiformis

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
1.1.3.17 choline + 2 O2 + H2O2 Arthrobacter globiformis
-
 betaine + 2 H2O2
-
 ?

Organism

EC Number Organism UniProt Comment Textmining
1.1.3.17 Arthrobacter globiformis Q7X2H8
-
-

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
1.1.3.17 3-hydroxypropyl-trimethylamine + 2 O2 + H2O2
-
 Arthrobacter globiformis ?
-
 ?
1.1.3.17 choline + 2 O2 + H2O2
-
 Arthrobacter globiformis betaine + 2 H2O2
-
 ?
1.1.3.17 choline + 2 O2 + H2O2 choline oxidase catalyzes the flavin-mediated, two-step oxidation of choline to glycine betaine with formation of betaine aldehyde as intermediate. Both the oxidation of the alcohol substrate and the aldehyde intermediate require molecular oxygen to accept electrons from the reduced flavin. The reaction of hydride transfer of choline oxidation is rate limiting for the overall turnover of the wild-type and the Glu312Asp enzymes with choline as substrate Arthrobacter globiformis betaine + 2 H2O2
-
 ?

Synonyms

EC Number Synonyms Comment Organism
1.1.3.17 choline-oxygen 1-oxidoreductase
-
 Arthrobacter globiformis

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
1.1.3.17 25
-
 assay at Arthrobacter globiformis

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
1.1.3.17 10
-
 assay at Arthrobacter globiformis

Cofactor

EC Number Cofactor Comment Organism Structure
1.1.3.17 FAD
-
 Arthrobacter globiformis

General Information

EC Number General Information Comment Organism
1.1.3.17 additional information in the active site of choline oxidase, Glu312 participates in binding the trimethylammonium group of choline, thereby positioning the alcohol substrate properly for efficient hydride transfer to the enzyme-bound flavin. Glu312 is the only negatively charged residue in the active site of the enzyme Arthrobacter globiformis
1.1.3.17 physiological function the reaction catalyzed by choline oxidase is of importance due to the trigger of glycine betaine accumulation in the cytoplasm of a number of plants and pathogenic bacteria in response to hyperosmotic and adverse temperature conditions to prevent dehydration and eventual cell death Arthrobacter globiformis