Selecting the ideal affinity tag for your protein production project

Proteos is an industry leader in the production of high-quality recombinant proteins for drug discovery research. What sets Proteos apart from the competition is our ability and willingness to customize every project to meet the specific needs of each client. Our team of highly skilled scientists have decades of experience in recombinant protein production and will work with you to design an optimized data-driven workflow.

Workflows for tackling challenging protein projects often utilize an affinity tag approach. Selection of the proper affinity tag prior to project initiation can be challenging yet critical to the ultimate success of the project.

Purity, yield, and cost are three, sometimes opposing, factors that need to be considered when selecting an affinity tag for protein purification. For example, the His-tag is a popular choice for recombinant proteins because purification by IMAC generates high yields at low costs. The drawback is that nonspecific interactions between endogenous proteins and the IMAC resin leads to some impurities. Alternatively, monoclonal anti-FLAG beads purify FLAG-tagged proteins with fewer contaminants than His/IMAC, but this specificity comes with lower yields and higher expenses. Prioritize purity, yield, and cost of protein purification in the order that is most suitable for the research project and downstream applications.

If specific buffer conditions are required for purification of the protein of interest, this simplifies the affinity tag selection process. Antibody-based purifications of epitope tags, like FLAG, are not compatible with reducing or denaturing agents. Denaturing conditions and low concentrations of reducing agents are tolerated during IMAC purification of His-tagged proteins, but metal chelators need to be avoided. Overall, having a purification strategy in mind during construct design facilitates selection of an affinity tag.

Our team will work with you to select the proper affinity tag and design a customized workflow to ensure that you project has the greatest likelihood of success. Contact us today to start the conversation.