Tricetin 3',4',5'-O-trimethyltransferase explained

Tricetin 3',4',5'-O-trimethyltransferase
Ec Number:	2.1.1.169

Tricetin 3',4',5'-O-trimethyltransferase (FOMT, TaOMT1, TaCOMT1, TaOMT2) is an enzyme with systematic name S-adenosyl-L-methionine:tricetin 3',4',5'-O-trimethyltransferase.^{[1] [2] [3]} This enzyme catalyses the following chemical reaction

\rightleftharpoons 3 S-adenosyl-L-homocysteine + 3',4',5'-O-trimethyltricetin (overall reaction)

(1a) S-adenosyl-L-methionine + tricetin

\rightleftharpoons S-adenosyl-L-homocysteine + 3'-O-methyltricetin

(1b) S-adenosyl-L-methionine + 3'-O-methyltricetin

\rightleftharpoons S-adenosyl-L-homocysteine + 3',5'-O-dimethyltricetin

(1c) S-adenosyl-L-methionine + 3',5'-O-dimethyltricetin

\rightleftharpoons S-adenosyl-L-homocysteine + 3',4',5'-O-trimethyltricetin

The enzyme from Triticum aestivum catalyses the sequential O-methylation of tricetin via 3'-O-methyltricetin, 3',5'-O-methyltricetin to 3',4',5'-O-trimethyltricetin.

Notes and References

1. Kornblatt JA, Zhou JM, Ibrahim RK . Structure-activity relationships of wheat flavone O-methyltransferase: a homodimer of convenience . The FEBS Journal . 275 . 9 . 2255–66 . May 2008 . 18397325 . 10.1111/j.1742-4658.2008.06377.x . free .
2. Zhou JM, Gold ND, Martin VJ, Wollenweber E, Ibrahim RK . Sequential O-methylation of tricetin by a single gene product in wheat . Biochimica et Biophysica Acta (BBA) - General Subjects . 1760 . 7 . 1115–24 . July 2006 . 16730127 . 10.1016/j.bbagen.2006.02.008 .
3. Zhou JM, Seo YW, Ibrahim RK . Biochemical characterization of a putative wheat caffeic acid O-methyltransferase . Plant Physiology and Biochemistry . 47 . 4 . 322–6 . April 2009 . 19211254 . 10.1016/j.plaphy.2008.11.011 .