ENZYME entry: EC 18.104.22.168
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- 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol + H(2)O(2) <=> 3,4-dimethoxybenzaldehyde + 2-methoxyphenol + glycolaldehyde + H(2)O
- 2 (3,4-dimethoxyphenyl)methanol + H(2)O(2) <=> 2 (3,4-dimethoxyphenyl)methanol radical + 2 H(2)O
- Involved in the oxidative breakdown of lignin by white-rot
- The reaction involves an initial oxidation of the heme iron by
hydrogen peroxide, forming compound I (Fe(IV)=O radical cation) at
the active site.
- A single one-electron reduction of compound I by an electron derived
from a substrate molecule yields compound II (Fe(IV)=O non-radical
cation), followed by a second one-electron transfer that returns the
enzyme to the ferric oxidation state.
- The electron transfer events convert the substrate molecule into a
transient cation radical intermediate that fragments spontaneously.
- The enzyme can act on a wide range of aromatic compounds, including
methoxybenzenes and nonphenolic beta-O-4 linked arylglycerol beta-
aryl ethers, but cannot act directly on the lignin molecule, which is
too large to fit into the active site.
- However larger lignin molecules can be degraded in the presence of
- It has been suggested that the free radical that is formed when the
enzyme acts on veratryl alcohol can diffuse into the lignified cell
wall, where it oxidizes lignin and other organic substrates.
- In the presence of high concentration of hydrogen peroxide and lack
of substrate, the enzyme forms a catalytically inactive form
- This form can be rescued by interaction with two molecules of the
free radical products.
- In the case of veratryl alcohol, such an interaction yields two
molecules of veratryl aldehyde.
|PRIAM enzyme-specific profiles||22.214.171.124|
|KEGG Ligand Database for Enzyme Nomenclature||126.96.36.199|
|IUBMB Enzyme Nomenclature||188.8.131.52|
|MEDLINE||Find literature relating to 184.108.40.206|
|Rhea expert-curated reactions||220.127.116.11|
|P49012, LIG2_PHACH; ||P21764, LIG3_PHACH; ||P11542, LIG4_PHACH; |
|P11543, LIG5_PHACH; ||P50622, LIG6_PHACH; ||P06181, LIG8_PHACH; |
|P31837, LIGA_PHACH; ||P20011, LIGA_TRAVE; ||P31838, LIGB_PHACH; |
|P20012, LIGB_TRAVE; ||P20013, LIGC_TRAVE; ||P20010, LIG_PHLRA; |
entries corresponding to 1.11.1.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.11.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.-.-.-