Each protein has a specific behavior and many parameters can vary (Stevens 2000). Protein'eXpert 1 has developed an expertise to determine optimal production conditions for recombinant proteins, and it provides several products and services in this field. One of these services is called the feasibility study which is a complete and standardized protein production study including cloning, expression and solubility tests, cell fractionation, purification, refolding assay (when necessary), quality control and delivery of 1-10 mg of soluble proteins. .