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Updated: Jun 28, 2026
10:49
Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
[Interaction between 5-lipoxygenase and allosteric effector--sodium dodecyl sulfate]
Ukrains'Kyi Biokhimichnyi Zhurnal (1999 )
|October 31, 2008
Summary
Sodium dodecyl sulfate (SDS) alters potato 5-lipoxygenase activity by affecting radical intermediate dissociation. This allosteric effector influences enzyme inhibition and thermoinactivation, impacting lipid peroxidation.
Area of Science:
- Biochemistry
- Enzymology
Context:
- Investigates the role of sodium dodecyl sulfate (SDS) as an allosteric effector in lipoxygenase catalysis within a micellar system.
- Examines the impact of hydrophobic bis-nitroxides on the oxidation of linoleic acid and linoleic alcohol by potato 5-lipoxygenase.
Purpose:
- To elucidate the mechanism by which SDS influences 5-lipoxygenase activity and stability.
- To determine the effect of SDS concentration and substrate type on enzyme inhibition by nitroxide compounds.
Summary:
- The study reveals that SDS concentration modulates the inhibitory effect of nitroxide compounds on 5-lipoxygenase, with inhibition varying based on substrate and effector presence.
- SDS did not significantly alter the pKa values of the enzyme's ionogenic groups.
- Thermodynamic analysis showed that SDS and the micellar system increase the rate constants and activation energy for 5-lipoxygenase thermoinactivation.
Impact:
- Findings suggest that SDS interaction with 5-lipoxygenase enhances the dissociation of radical intermediates from the active site.
- These results hold physiological significance, particularly concerning the involvement of lipoxygenases in membrane lipid peroxidation.
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