Mitmekihilistes

Mitmekihilistes, also known as the "multihistidine tag," is a short peptide sequence consisting of six consecutive histidine residues (His6). It is commonly used in molecular biology and biochemistry for various applications, particularly in protein purification and characterization. The His6 tag is often fused to the C-terminus of a target protein during recombinant protein expression. This fusion allows for the specific binding of the tagged protein to a nickel-affinity resin, which contains immobilized nickel ions. The high affinity of histidine for nickel enables efficient purification of the target protein from a complex mixture of proteins.

The His6 tag is particularly useful in the purification of recombinant proteins expressed in bacterial systems, such as Escherichia coli. After induction of protein expression, the bacterial cells are lysed, and the cell lysate is passed through a nickel-affinity column. The His6-tagged protein binds to the column, while other proteins in the lysate pass through. The column is then washed to remove unbound proteins, and the His6-tagged protein is eluted using a buffer containing imidazole, a competitive ligand for nickel. The eluted protein can then be further purified and characterized.

In addition to protein purification, the His6 tag can also be used for protein immobilization and affinity chromatography. The His6 tag can be covalently attached to a solid support, such as a bead or a membrane, to create an affinity matrix. This matrix can be used to capture and purify target proteins from complex mixtures, or to study protein-protein interactions.

The His6 tag is a versatile and widely used tool in molecular biology and biochemistry. Its high affinity for nickel and its stability under a wide range of conditions make it an ideal choice for protein purification and characterization. However, it is important to note that the His6 tag can interfere with protein folding and function, and that its use should be carefully considered in the context of the specific application.