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11:13
Covalent Immobilization of Proteins for the Single Molecule Force Spectroscopy
Published on: August 20, 2018
Hydrophobic interactions are the prevalent force in bromelain:Fab' complex
P Gupta1, M Saleemuddin, R H Khan
1Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh 202002, India. pawan_g75@hotmail.com
Biochemistry. Biokhimiia
|February 21, 2006
Summary
This study investigated the stability of the bromelain:Fab complex. Hydrophobic interactions are crucial for binding, while electrostatic interactions play a lesser role in complex stability.
Area of Science:
- Biochemistry
- Protein-protein interactions
- Immunology
Background:
- Polyclonal antibodies against stem bromelain were generated in rabbits.
- Fab monomers were isolated from immune sera, forming a 1:1 complex with bromelain.
Purpose of the Study:
- To investigate the stability of the bromelain:Fab complex.
- To elucidate the role of hydrophobic and electrostatic interactions in complex formation.
Main Methods:
- Far and near-UV Circular Dichroism (CD) spectroscopy.
- Fluorescence spectroscopy.
- Gel filtration chromatography.
Main Results:
- The bromelain:Fab complex remained stable with up to 1.8 M NaCl, indicating minimal electrostatic contribution.
- Complex dissociation was observed in the presence of 5% (v/v) methanol.
- Spectral data and gel filtration suggest hydrophobic interactions are critical for binding.
Conclusions:
- Hydrophobic interactions play a significant role in the binding of Fab monomers to bromelain.
- Electrostatic interactions are less critical for the stability of this protein complex.
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