Abstract��
veratryl alcohol,as a non phenolic lignin model compound,has a high redox potential.Soybean hull peroxidase(SHP) is unable to oxidize veratryl alcohol in its normal peroxidatic circle,but has been shown to catalyze the oxidation of veratryl alcohol to veratraldehyde in the presence of reduced glutathione,Mn 2+ ,and an organic acid metal chelator such as lactate.The optimum pH of the reaction is 4.2.The kinetic profiles indicate a reaction mechanism of the compulsory order type wherein a specific substrate must react with SHP to form an activated complex that will react with a second substrate.An apparent K M for veratryl alcohol of 4.3 mmol/L at optimum glutathione concentration and an apparent K M for glutathione of 4.8 mmol/L at optimum veratryl alcohol were obtained.In addition to glutathione,dithiothreitol,mercaptoethanol and L cysteine are capable of promoting veratryl alcohol oxidation.Non thiol reductants,such as ascorbate,do not support oxidation of veratryl alcohol.
.Study on the Thiol and Mn~(2+)-mediated Oxidation of Veratryl Alcohol by Soybean Hull Peroxidase [J] Chinese Journal of Biochemistry and Molecular Biol, 1999,V15(05 ): 808-808
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