Key Factors for Successful Protein Purification and Crystallization

Protein purification and crystallization problems have been noticed for many years. The strategies developed for protein solubility and crystallization have improved the protein production and provide high-resolution crystals for structural studies. The protein solubility is achieved by the Site-directed mutagenesis that generates the hydrophobic to hydrophilic mutations. However, the purity and rate of crystallization success still needs to be improved. In this review, the key factors such as the expression system, Affinity –Tags, solubility, reducing or oxidizing environment, denaturing agents, concentration of precipitant, concentration of protein, ionic strength, isoelectric point and pH, temperature, additives, ligands, presence of substrates, coenzymes, mutation, that affect both protein purification and crystallization are discussed in detail. The aim of this review is to have a profound discussion on these key factors and analyze them in relation to both aspects; purification and crystallization and provide a fruitful advice for boosting the production rate of protein and crystallization effectively.