Suzhou protein purification system: protein purification methods and their advantages and disadvantages (4)
Below is a small series of SCG protein purification system to introduce the hydrophobic effect of protein purification methods.
Chromatographic proteins are composed of hydrophobic and hydrophilic amino acids. Hydrophobic amino acids are located in the center of protein spatial structure, away from water molecules on the surface. Hydrophilic amino acid residues are located on the surface of the protein. Since hydrophilic amino acids attract many water molecules, the entire protein molecule is usually surrounded by water molecules, and hydrophobic amino acids are not exposed. In the environment of high salt concentration, the hydrophobic region of the protein will be exposed and bind to the hydrophobic ligand on the surface of the hydrophobic medium. Different proteins have different hydrophobicity, and the magnitude of the hydrophobic force is different. By gradually reducing the salt concentration in the buffer solution to wash the column, when the salt concentration is very low, the protein returns to its natural state, and the weakened hydrophobic force is eluted.
The selectivity of the hydrophobic resin is determined by the structure of the hydrophobic ligand. Commonly used linear ligands are alkyl ligands and arylligands. Strong. The choice of the ideal resin type should be determined according to the chemical properties of the target protein. The resin with too strong binding force cannot be selected, and the resin with too strong binding force will be difficult to elute. . To make it easier to choose the right medium, Amersham Biosciences has launched a hydrophobic interaction resin selection kit, which includes 5 different resins for comparison. Hydrophobic chromatography is very suitable as the next step in ion exchange purification, because hydrophobic interaction chromatography is applied at high salt concentration, and the product obtained from ion exchange can be used without changing the buffer. The protein is eluted in the low-salt buffer, and the step of replacing the buffer before the next purification is omitted, which not only saves time but also reduces protein loss.
The above is the hydrophobic effect of protein purification method. If you want to know more about SCG protein purification system, please pay attention to Suzhou Saipu Instrument Co., Ltd.