Peroxidase activity of hemoproteins. III. Activation of methemoglobin and catalase by formamide and guanidine.

摘要: Abstract Methemoglobin and catalase are highly activated as peroxidase when treated with formamide or guanidine. As the reagent concentration increases, activation proceeds stepwise through a few stationary levels of activity. The in earlier steps is due to splitting native molecules into successively smaller subunits, accompanied by spectral changes heme groups bound subunits. In later steps, group forms complex(es) either on subunits or, being detached from them, highest activity obtained. Absolute rate constants, k 1 4 were determined for hematin complexes at their optimum conditions. values (rate constant reaction hydrogen donor) comparable order value horseradish peroxidase, whereas H 2 O ) much than horse-radish peroxidase. role apoproteins common peroxidases discussed view results obtained denatured hemoproteins.