Abstract
Abstract Superoxide dismutase catalyzes the decay of O2-, generated by pulse radiolysis. The enzymatic reaction was first order with respect to enzyme and to O2- and the rate constant, which was 2.3 x 109 m-1 s-1 at pH 7.0 and 20–25°, was not much affected by pH, in the range 4.8 → 9.5. Boiling the enzyme or reversibly removing its copper prosthetic group caused loss of catalytic activity. EDTA had no effect on the enzyme-catalyzed dismutation of superoxide radicals, but did eliminate catalysis by Cu++.
Keywords
RadiolysisSuperoxide dismutaseChemistryCatalysisPulse (music)SuperoxidePhotochemistryAction spectrumRadicalBiochemistryEnzymePhysics
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Publication Info
- Year
- 1972
- Type
- article
- Volume
- 247
- Issue
- 15
- Pages
- 4839-4842
- Citations
- 491
- Access
- Closed
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Cite This
Dina Klug,
Joseph Rabani,
Irwin Fridovich
(1972).
A Direct Demonstration of the Catalytic Action of Superoxide Dismutase through the Use of Pulse Radiolysis.
Journal of Biological Chemistry
, 247
(15)
, 4839-4842.
https://doi.org/10.1016/s0021-9258(19)44987-9
Identifiers
- DOI
- 10.1016/s0021-9258(19)44987-9