Sulfhydryl groups catalase

Plant amine oxidase from Euphorbia characias is not sensitive to hydrogen peroxide in the absence of substrate [128]. In the presence of substrate and in absence of catalase, however, either hydrogen peroxide formed by the reaction or more rapidly the hydrogen peroxide added before initiating the enzymatic reaction causes total inactivation. The inactivation is considered to be related to the sulfhydryl group... 

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