The enzyme-substrate compounds of bacterial catalase and peroxides

作者：B Chance, David E. Herbert · 发表于：Biochemical Journal · 年份：1950 · DOI：10.1042/bj0460402 · 被引用次数：162 · 研究领域：Enzyme-mediated dye degradation、Protein Interaction Studies and Fluorescence Analysis、Electrochemical Analysis and Applications

CHANCE I950catalase haematins are bound as complex II and at pH 3*6 nearly all are, under the particular experi- mental conditions.8. The formation of complex II is responsible for the decrease of catalase activity during the usual Kat.f. determination and for the rapid decrease of catalase activity in acid solutions.9. The steady-state concentration of hydrogen peroxide in the presence of catalase and the notatin system is very small.Under particular experimental conditions, the hydrogen peroxide concentration is calculated to be of the order of 10-9M.10.The very rapid reaction of catalase-bound methyl hydrogen peroxide I with hydrogen peroxide can be studied m greater detail when hydrogen per- oxide is continuously generated by the notatin system.The velocity constant for this reaction is of the same order as that ofcatalase-hydrogen peroxide I with hydrogen peroxide (3.5 x.107M-1 sec.-').In this reaction, hydrogen peroxide acts as an acceptor as in peroxidatic reactions of complex I with ethanol, but is about 30,000 times as active as ethanol.The author owes many thanks to Prof. D.