Description
General description
Research Area: Cell Signaling
Catalase from bovine liver is a tetramer consisting of 4 equal subunits each with a 60 kDa molecular weight. Each of these subunits contains iron bound to a protoheme IX group. The enzyme will also strongly bind to NADP, where NADP and the heme group are within 13.7 angstroms.
Application
Catalase acts as a natural antioxidant to study the roles of reactive oxygen species in gene expression and apoptosis. It has also been used to protect against oxidative damage to proteins, lipids, and nucleic acids. Industrially, catalzes have been used to remove hydrogen peroxide added to milk and cheese, in textile bleaching, and to examine its positive effects on the viability of DNA-repair mutants of E. coli.
Catalase from bovine liver may be used:
to prepare H₂O₂-O₂ based biocathode for applications in glucose biofuel cells
to study the kinetic properties and storage stability of catalase immobilized on to florisil
in glutathione-mediated superoxide generation in an aqueous solution
Biochem/physiol Actions
Catalase, an antioxidant enzyme found in all aerobic organisms, catalyzes the degradation of hydrogen peroxide, a byproduct of metabolic processes, into less harmful water and oxygen. It can also react with alkylhydrogen peroxides, such as methylperoxide and ethylperoxide and the second H₂O₂ molecule can be replaced by methanol, ethanol, propanol, formate and nitrate as a hydrogen donor. Catalase enzyme uses either iron (Fe) or manganese (Mn) as cofactor, and are classified as Fe-CAT or Mn-CAT.
Preparation Note
This product is offered as a catalase suspension in water containing 0.1% (w/v) thymol with activity of 40,000-60,000 units/mg protein. To remove the thymol preservative, the catalase crystals may be pelleted by centrifugation, the supernatant, discarded, the pellet resuspended in water, and then pelleted again. The enzyme is soluble in 50 mM potassium phosphate buffer at 1 mg/mL and pH 7.0.
Other Notes
One unit will decompose 1.0 μmole of H₂O₂ per min at pH 7.0 at 25 °C, while the H₂O₂ concentration falls from 10.3 to 9.2 mM, measured by the rate of decrease of A₂₄₀.
Disclaimer
Solutions of catalse should not be frozen. Frozen solution will result in a 50-70% loss of activity.
