title: Kinetics of the H2O2-dependent ligninase-catalyzed oxidation of veratryl alcohol in the presence of cationic surfactant studied by spectrophotometric technique.
abstract: The kinetics of ligninase-catalyzed oxidation of veratryl alcohol (VA) by H(2)O(2) in the aqueous medium containing cationic surfactant cetyltrimethylammonium bromide (CTAB) has been investigated using spectrophotometric technique. Steady-state kinetic studies at different concentrations of CTAB indicate that the reaction follows a ping pong mechanism and the mechanism always holds but the kinetic parameters vary with CTAB concentrations. CTAB is a weak inhibitor for ligninase; it lowers the maximum initial velocity. CTAB also causes the Michaelis constant of H(2)O(2) to decrease dramatically and that of VA to increase markedly. Based on the changes in kinetic parameters of the enzyme-catalyzed reaction at different CTAB concentrations (lower than, near to and larger than its critical micelle concentration) and the effects of the CTAB monomer and the micelles on the spectra of VA and its corresponding aldehyde, a conclusion could be made that modification of the enzymatic protein by the surfactant monomer should be responsible for the above-mentioned results.
authors.affiliation: Key Lab for Colloid and Interface Chemistry of the Education Ministry of China, Shandong University, Jinan 250100, People's Republic of China.
authors.forename: Airong
authors.initials: A
authors.lastname: Liu
authors.forename: Xirong
authors.initials: X
authors.lastname: Huang
authors.forename: Shaofang
authors.initials: S
authors.lastname: Song
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Xuemei
authors.initials: X
authors.lastname: Lu
authors.forename: Yinbo
authors.initials: Y
authors.lastname: Qu
authors.forename: Peiji
authors.initials: P
authors.lastname: Gao
mesh_terms: D001592:Benzyl Alcohols / Q000737:chemistry / Q000378:metabolism*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007700:Kinetics; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000378:metabolism*; D013053:Spectrophotometry; D013501:Surface-Active Agents / Q000378:metabolism
chemical_list: D001592:Benzyl Alcohols; D002593:Cetrimonium Compounds; D013501:Surface-Active Agents; D006861:Hydrogen Peroxide; D010105:Oxygenases; C044391:ligninase; C042197:veratryl alcohol; D000077286:Cetrimonium