Open AccessThe reaction of hemin with H 2 O 2
Author(s) -
KREMER Mordechai L.
Publication year - 1989
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1989.tb15162.x
Subject(s) - hemin , absorbance , chemistry , kinetics , decomposition , catalysis , absorption (acoustics) , reaction rate constant , photochemistry , ion , absorption spectroscopy , inorganic chemistry , analytical chemistry (journal) , heme , materials science , chromatography , organic chemistry , quantum mechanics , composite material , enzyme , physics
The kinetics of formation of the dominant intermediate (C II ) formed between hemin and H 2 O 2 has been studied by the stopped‐flow method. C II is preceded by a precursor (C I ) for which a steady state is established at an early stage of the reaction. The formation of C I from hemin and H 2 O 2 causes only a marginal change in the optical absorbance ( A ). The transition C I °C II is accompanied by a substantial decrease of A in the Soret region. Relevant rate constants (or combinations of them) and the molar absorption coefficients of the intermediates at 400 nm have been determined. The absorption spectrum of C II in the Soret region has been evaluated. Aspects of the catalysis of decomposition of H 2 O 2 by hemin in relation to the Fe 3+ ion and catalase are discussed.