Monoclonal Anti-His Tag

A polyhistidine-tag is an amino acid motif in proteins that consists of at least five histidine (His) residues, often at the N- or C-terminus of the protein. It is also known as hexa histidine-tag, 6xHis-tag. Polyhistidine-tags are often used for affinity purification of polyhistidine-tagged recombinant proteins expressed in Escherichia coli and other prokaryotic expression systems. Affinity purification using a polyhistidine-tag usually results in relatively pure protein when the recombinant protein is expressed in prokaryotic organisms. Depending on downstream applications including the purification of protein complexes to study protein interactions, purification from higher organisms such as yeasts or other eukaryotes may require a tandem affinity purification using two tags to yield higher purity. The most common polyhistidine tags are formed of six histidine (6xHis tag) residues - preceded by Methionine - which are added at the C-terminal or N-terminal of the protein of interest.

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