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Interaction and complex formation between catalase and cationic polyelectrolytes: chitosan and Eudragit E100
Valeria Boeris1, Diana Romanini, Beatriz Farruggia
1Bioseparation Lab. Chemical-Physics Department, Faculty of Biochemical and Pharmaceutical Sciences, CONICET, FonCyT and CIUNR, National University of Rosario, Suipacha 570 (S2002RLK) Rosario, Argentina.
International Journal of Biological Macromolecules
|April 29, 2009
Summary
Catalase interactions with chitosan and Eudragit E100 were studied. These cationic polyelectrolytes can effectively precipitate and isolate catalase without altering its structure or activity.
Area of Science:
- Biochemistry
- Polymer Science
- Protein Chemistry
Background:
- Catalase enzyme is crucial in cellular defense against oxidative stress.
- Cationic polyelectrolytes like chitosan and Eudragit E100 have diverse applications.
- Understanding protein-polyelectrolyte interactions is vital for biomaterial development and protein purification.
Purpose of the Study:
- To investigate the interactions between catalase and two cationic polyelectrolytes: chitosan and Eudragit E100.
- To characterize the resulting polymer-protein complexes and their stability.
- To evaluate the potential of these polyelectrolytes for catalase isolation and purification.
Main Methods:
- Turbidimetry
- Circular dichroism spectroscopy
- Fluorescence spectroscopy
- Evaluation of pH, ionic strength, and anion effects on complex formation.
Main Results:
- Catalase conformation remained largely unchanged during interactions with chitosan and Eudragit E100.
- Complex formation is primarily driven by net coulombic interactions, sensitive to ionic strength.
- Both polyelectrolytes effectively precipitated approximately 80% of catalase from solution.
- Dissolved precipitates retained catalase's tertiary, secondary structure, and enzymatic activity.
Conclusions:
- Chitosan and Eudragit E100 are effective in precipitating catalase without compromising its structural integrity or enzymatic function.
- These polyelectrolytes provide a viable framework for isolating catalase and other proteins with slightly acidic isoelectric points.
- The study highlights a promising method for protein purification using specific polymer-protein interactions.
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