The HIS tag is a commonly used protein tag that consists of multiple amino acids with histidine residues (HIS). His tag has the following characteristics:
1.Affinity: His tag has a high affinity for metal ions such as nickel and copper. This affinity allows the His-tag to bind to metal ions to form stable complexes, enabling specific capture and purification of proteins.
2.Small size: The HIS tag is relatively small and typically consists of 6-10 histidine residues. This small size makes the HIS tag important for protein structure and functionThe impact is smaller, which is able to maintain the natural properties of the target protein to a large extent.
3.Reversibility: The binding of the HIS tag to metal ions is reversible and can be dissociated by changing buffer conditions, adding chelating agents, etc. This reversibility allows the His-tag to be easily removed after purification, resulting in a pure protein of interest.
4.Quantitative: Since the binding of the HIS tag to metal ions is controllable, the presence and concentration of the protein of interest can be quantified by measuring the concentration of the metal ion or the activity of the labeled enzyme.
5.Versatility: The HIS tag is a universal tag that is suitable for a variety of expression systems and purification methods. Whether it is a prokaryotic expression system, a eukaryotic expression system, or an in vitro transcription translation system, His-tags can be used for protein expression and purification.
6.Reliability: The HIS tag is a widely validated and applied tag with high reliability and stability. In terms of protein expression, purification and detection, His tags have been widely used and have achieved good results.
In summary, the HIS tag has the characteristics of high affinity, small size, reversibility, quantification, versatility and reliability, making it one of the commonly used protein tags and widely used in research fields such as protein expression, purification and detection.