Recombinant protein purification by self-cleaving elastin-like polypeptide fusion tag

Area of Science:

• Biotechnology
• Protein Biochemistry
• Molecular Biology

Background:

• Recombinant protein purification from E. coli often requires complex chromatographic techniques.
• Existing methods may involve affinity resins or enzymatic tag cleavage, adding steps and potential contaminants.
• Developing simpler, efficient purification strategies is crucial for protein research and applications.

Purpose of the Study:

• To present a rapid, nonchromatographic method for purifying recombinant proteins expressed in E. coli.
• To demonstrate the utility of a thermally responsive elastin-like polypeptide (ELP) tag for protein purification.
• To provide a detailed protocol for cloning and purification using the ELP tag system.

Main Methods:

• Utilizing an elastin-like polypeptide (ELP) tag fused to the target recombinant protein.
• Employing a mild temperature shift to precipitate the ELP-tagged protein.
• Inducing self-cleavage of the ELP tag via a mild pH shift.
• Removing the cleaved ELP tag through a subsequent thermal precipitation step.

Main Results:

• Achieved rapid and simple nonchromatographic purification of recombinant proteins.
• Demonstrated successful removal of the ELP tag without the need for affinity chromatography or proteases.
• Obtained purified native protein targets free from the purification tag.
• Provided a comprehensive protocol for both cloning and purification.

Conclusions:

• The ELP tagging system offers an efficient and accessible alternative for recombinant protein purification.
• This method simplifies protein purification workflows, reducing time and resources.
• The protocol is adaptable for various target proteins expressed in E. coli.