Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen into the other donor
The spinach enzyme, which is located in the chloroplast, contains a Rieske-type [2Fe-2S] cluster, and probably also a mononuclear Fe centre. Requires Mg2+. Catalyses the first step of glycine betaine synthesis. In many bacteria, plants and animals, betaine is synthesized in two steps: (1) choline to betaine aldehyde and (2) betaine aldehyde to betaine. Different enzymes are involved in the first reaction. In plants, the reaction is catalysed by this enzyme whereas in animals and many bacteria it is catalysed by either membrane-bound EC 1.1.99.1 (choline dehydrogenase) or soluble EC 1.1.3.17 (choline oxidase) [7]. The enzyme involved in the second step, EC 1.2.1.8 (betaine-aldehyde dehydrogenase), appears to be the same in plants, animals and bacteria. In some bacteria, betaine is synthesized from glycine through the actions of EC 2.1.1.156 (glycine/sarcosine N-methyltransferase) and EC 2.1.1.157 (sarcosine/dimethylglycine N-methyltransferase).
History
EC 1.14.15.7 created 2001, modified 2002 (EC 1.14.14.4 created 2000, incorporated 2002), modified 2005, modified 2011
Rathinasabapathi B, Burnet M, Russell BL, Gage DA, Liao PC, Nye GJ, Scott P, Golbeck JH, Hanson AD
Title
Choline monooxygenase, an unusual iron-sulfur enzyme catalyzing the first step of glycine betaine synthesis in plants: prosthetic group characterization and cDNA cloning.
Waditee R, Tanaka Y, Aoki K, Hibino T, Jikuya H, Takano J, Takabe T, Takabe T
Title
Isolation and functional characterization of N-methyltransferases that catalyze betaine synthesis from glycine in a halotolerant photosynthetic organism Aphanothece halophytica.
