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07:19
Affinity Purification of a 6X-His-Tagged Protein using a Fast Protein Liquid Chromatography System
Published on: April 26, 2024
Metal-chelate affinity precipitation of proteins using responsive polymers
Bo Mattiasson1, Ashok Kumar, Alexander E Ivanov
1Department of Biotechnology, Center for Chemistry and Chemical Engineering, Lund University, SE-22100 Lund, Sweden. Bo.Mattiasson@biotek.lu.se
Nature Protocols
|April 3, 2007
Summary
This study introduces responsive polymers for simpler, cost-effective protein purification via affinity precipitation. This method achieves high yields for recombinant His-tag proteins and naturally binding proteins.
Area of Science:
- Biochemistry
- Polymer Chemistry
- Biotechnology
Background:
- Affinity precipitation offers a simpler alternative to traditional protein purification methods like chromatography.
- Responsive polymers enable tunable precipitation based on environmental stimuli such as temperature or pH.
Purpose of the Study:
- To develop and present protocols for synthesizing specific responsive polymers.
- To demonstrate the efficacy of these polymers in protein purification through affinity precipitation.
Main Methods:
- Synthesis of thermoresponsive 1-vinylimidazole:N-isopropylacrylamide copolymers.
- Application of metal chelate affinity precipitation for purifying recombinant His-tag proteins and proteins with natural metal binding groups.
Main Results:
- Successful synthesis of responsive polymers with specific protein affinity.
- Achieved protein purification yields of 80% and higher.
- Demonstrated a purification process time of 2-3 hours.
Conclusions:
- Affinity precipitation using synthesized responsive polymers is a simpler and more cost-effective protein purification strategy.
- The method is efficient for various protein types, including recombinant His-tag proteins.
- Optimization of polymer composition and chelating ions enhances target protein recovery.
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