EC Number |
Reaction |
Reference |
---|
1.13.11.3 | 3,4-dihydroxybenzoate + O2 = 3-carboxy-cis,cis-muconate |
examining a distorted trigonal-bipyramidal geometry observed for the non-heme iron center in protocatechuate 3,4-dioxygenase by utilizing a sterically hindered iron salen complex gives following results: the extent of a structural change of the iron center from a preferred square-pyramidal to a distorted trigonal-bipyramidal geometry varies with the external ligand that is bound in the order Cl <
674004 |
|
1.13.11.3 | 3,4-dihydroxybenzoate + O2 = 3-carboxy-cis,cis-muconate |
proposed mechanism based on Mössbauer, EPR and inhibition kinetic data |
439486 |
1.13.11.3 | 3,4-dihydroxybenzoate + O2 = 3-carboxy-cis,cis-muconate |
proposed reaction mechanism |
439506 |
1.13.11.3 | 3,4-dihydroxybenzoate + O2 = 3-carboxy-cis,cis-muconate |
the computational (hybrid density functional method B3LYP) results of the catalytic cycle of the intradiol dioxygenases suggest: (1)binging of the substrate as a dianion (2) binding of dioxygen to the metal aided by an electron transfer from the substrate to O2 (3) formation of a bridging peroxo intermediate and its conformational change, which opens the coordination site trans to His462, (4) binding of a neutral XOH ligand (H2O or Tyr447) at the open site, (5) proton transfer from XOH to the neighboring peroxo ligand yielding the hydroperoxo intermediate, (6) a Criegee rearrangment leading to the anhydride intermediate (the criegee mechanism requires an in-plane oriantation of the involved two oxygen and two carbon atoms. Under some conditions homolytic O-O bond cleavage might compete with the Criegee rearangment.) and (7) hydrolysis of the anhydride to the final acyclic product. |
674180 |