Catalase

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MitoPedia

Catalase

Description

Catalase catalyzes the dismutation of hydrogen peroxide to water and oxygen. Perhaps all cells have catalase, but mitochondria of most cells lack catalase. Cardiac mitochondria are exceptional in having mt-catalase activity (rat heart mitochondria: Radi et al 1991; mouse heart mitochondria: Rindler et al 2013).

Abbreviation: Ctl

Reference: Radi 1991 J Biol Chem, Rindler 2013 J Biol Chem, MiPNet09.12



MitoPedia topics: Enzyme 

Communicated by Gnaiger E (2015-03-05).

Application in HRR

Clt: Catalase (from bovine liver, lyophilized powder; 2,000-5,000 U/mg protein); Sigma C 9322; store at -20 °C.

Catalase is included in the mitochondrial respiration medium MiR06 (MiR06 = MiR05 plus catalase), so as to allow for re-oxygenation of the respiration medium (without lifting the stopper and risking the introduction of air bubbles) by addition of a small volume of a 200 mM stock solution of H2O2.

Preparation of catalase stock solution

Stock solution: 112,000 U/mL (dissolved in MiR05)
Example: 'Catalase lypophilized powder; 2,800 U/mg solid and 3,500 units/mg protein'
1) Use 'units/mg solid' for your calculations
2) Result: 40 mg catalase powder (2,800 U/mg) are dissolved in 1 mL MiR05 to obtain a catalase stock solution with 112,000 U/mL.
3) Divide into 0.2 mL portions.
4) Store frozen at -20 °C.


Unit definition: * Units of enzymatic activity (U) in µmol/min; assay used by Sigma Aldrich: ' 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. '


Oxygraph-2k manual titrations MiPNet09.12 O2k-Titrations

  • Titration volume: 5 µL Ctl using a 25 µL syringe (2 mL O2k-chamber).
  • Final concentration: 280 U/mL.