tBOOH acts as a suicide substrate for catalase.
The effects of t-butyl hydroperoxide (tBOOH) on bovine liver catalase were investigated. tBOOH is accepted as a substrate of catalase and in the absence of hydrogen donors leads to a destruction of the enzyme via compound II formation. During the decomposition of this enzyme-substrate complex catalase serves as internal hydrogen donor which results in destruction of the enzyme. Evidence for this destruction is given by: a decrease of the Soret band in the uv/vis spectrum, iron release from the enzyme, decrease of the catalatic activity of the enzyme measured by oxygen release from hydrogen peroxide. Hydrogen donors like NADH and o-dianisidine have been found to protect the enzyme from destruction by tBOOH but lead to a structural alteration of the enzyme, shown by alteration of the electrophoretic mobility. In the presence of the hydrogen donor tBOOH is completely reduced to t-butanol, which is thought to proceed in a peroxidase-like reaction.
Pichorner
H
H
Institut für Chemie, Universität für Bodenkultur, Vienna, Austria.
Jessner
G
G
Ebermann
R
R
D002374:Catalase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007501:Iron / Q000032:analysis / Q000378:metabolism; D007700:Kinetics; D009243:NAD / Q000494:pharmacology; D016877:Oxidants / Q000378:metabolism* / Q000494:pharmacology; D010545:Peroxides / Q000378:metabolism* / Q000494:pharmacology; D013053:Spectrophotometry; D013379:Substrate Specificity; D020122:tert-Butylhydroperoxide
D016877:Oxidants; D010545:Peroxides; D009243:NAD; D020122:tert-Butylhydroperoxide; D007501:Iron; D002374:Catalase