Cell-free expression feasibility

Each protein requires specific conditions for expression, particularly in cell-free environments.

Protéus offers a unique service to test the feasibility of expressing your protein in cell-free conditions using Phenomics™, and to identify the optimal conditions for your proteins.

Starting from the gene, Protéus will test in parallel the expression of your protein in four different cell-free systems (E.coli, Pseudomonas, Bacillus and Trichoderma) and more than 30 expression conditions. Since the expression is focused on the protein to express, ³⁵S labelling can be used. The relative expression levels are then compared by SDS-PAGE and autoradiography.

This expression profiling will allow identifying which PheMix™ (translation reagents) and conditions best express your protein for subsequently scaling up the expression.

• Test the feasibility of cell-free expression for your protein
• Rapid determination of optimal cell-free expression conditions
• Design of customised Phenomics™ cell-free expression kits

• A unique range of prokaryotic and eukaryotic systems
• A complete panel of over 30 cell-free expression conditions
• Parallel evaluation allowing to rapidly focus on successful conditions
• Development of customised expression conditions adapted to your protein

Please provide:

• Your cDNA cloned in a standard vector. We strongly recommend to send purified plasmids (10 µg in 40 µl TE buffer).
• Corresponding electronic maps and sequences

Protéus can also prepare synthetic genes (wild-type or codon optimised) starting from your electronic sequences (Cf gene synthesis option).
Tags and cleavage sites may be added on your demand to ease purification and downstream processing.

We deliver microtiter plates containing your protein expressed under the different conditions and including negative controls. Each plate comes with a map which gives a summary description of the conditions used. In this case, the proteins are not radiolabelled.

Optionally, Protéus also provides an assessment of expression yields, measured by SDS-PAGE Electrophoresis. In this case, the protein is radiolabelled and we deliver the images of the autoradiographies in order to define the best expression system from the expression yield.