The intramolecular kinetic deuterium isotope effects (k(H)/k(D) =4.6-4.9) determined in the H2O2-induced oxidation of the racemic and enantiomeric forms of alpha -monodeuterated veratryl alcohol catalysed by lignin peroxidase (UP) are very similar to those determined in the-oxidation of racemic alpha -monodeuterated veratryl alcohol promoted either by a LiP model compound (a water soluble iron porphyrin using m-chloroperbenzoic acid as the oxidant) (k(H)/k(D) = 4.2) or by potassium 12-tungstocobalt(III) ate, a genuine-one-electron oxidant (k(H)/k(D) = 4.5). These results indicate that very likely veratryl alcohol radical cation, once generated by the LiP-H2O2 system, is released from the enzyme and is deprotonated by the medium.
Kinetic deuterium isotope effect in the oxidation of veratryl alcohol promoted by lignin peroxidase and chemical oxidants / Baciocchi, Enrico; Gerini, Maria Francesca; Patricia J., Harvey; Lanzalunga, Osvaldo; Alma, Prosperi. - In: JOURNAL OF THE CHEMICAL SOCIETY. PERKIN TRANSACTIONS 2. - ISSN 1472-779X. - 9(2001), pp. 1512-1515. [10.1039/b104467m]
Kinetic deuterium isotope effect in the oxidation of veratryl alcohol promoted by lignin peroxidase and chemical oxidants
BACIOCCHI, Enrico;GERINI, Maria Francesca;LANZALUNGA, Osvaldo;
2001
Abstract
The intramolecular kinetic deuterium isotope effects (k(H)/k(D) =4.6-4.9) determined in the H2O2-induced oxidation of the racemic and enantiomeric forms of alpha -monodeuterated veratryl alcohol catalysed by lignin peroxidase (UP) are very similar to those determined in the-oxidation of racemic alpha -monodeuterated veratryl alcohol promoted either by a LiP model compound (a water soluble iron porphyrin using m-chloroperbenzoic acid as the oxidant) (k(H)/k(D) = 4.2) or by potassium 12-tungstocobalt(III) ate, a genuine-one-electron oxidant (k(H)/k(D) = 4.5). These results indicate that very likely veratryl alcohol radical cation, once generated by the LiP-H2O2 system, is released from the enzyme and is deprotonated by the medium.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.