Interactions of anionic surfactants with methemoglobin
1Institute of Applied Radiation Chemistry, Faculty of Chemistry, Technical University of Lodz, Wroblewskiego 15, 93-590 Lodz, Poland. lgebicka@mitr.p.lodz.pl
Colloids and Surfaces. B, Biointerfaces
|December 7, 2010
Summary
Anionic surfactants sodium dodecyl sulphate (SDS) and sodium bis(2-ethylhexyl) sulfosuccinate (AOT) alter methemoglobin (metHb) structure and activity. Surfactant interactions reduce metHb peroxidase activity and increase heme susceptibility to oxidative damage.
Area of Science:
- Biochemistry
- Physical Chemistry
- Spectroscopy
Background:
- Methemoglobin (metHb) is a form of hemoglobin with oxidized iron, affecting oxygen transport.
- Anionic surfactants like SDS and AOT are widely used in various applications and can interact with proteins.
Purpose of the Study:
- To investigate the interactions between SDS and AOT with methemoglobin.
- To understand how these surfactants affect metHb's structure, activity, and heme environment.
Main Methods:
- Conventional and stopped-flow absorption spectroscopy.
- Fluorescence spectroscopy.
- Analysis of absorption spectra in AOT reverse micelles.
Main Results:
- Both SDS and AOT in monomeric form convert metHb to reversible hemichrome.
- Surfactant interactions diminish metHb's peroxidase-like activity and increase heme susceptibility to H2O2 damage.
- In micellar solutions and AOT reverse micelles, pentacoordinated ferric species of metHb is predominant.
Conclusions:
- Surfactant-induced conformational changes in metHb's heme environment occur independently of tertiary structure alterations.
- SDS and AOT significantly impact metHb's functional and structural properties.
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