Cobalt(III) as a Stable and Inert Mediator Ion between NTA and His6-Tagged Proteins

摘要

The Nr~+-mediated interaction between the hexahistidine tag (His6-tag) and nitrilotriacetic acid (NTA) has been shown to be a flexible and reliable way to selectively bind recombinant proteins to NTA-functionalized molecules and materials. The small size of the tag, the site-specific interaction, and the very mild conditions for this interaction, which do not interfere with the native activity of the proteins make the system widely applicable and are the reason for the large library of existing His-tagged proteins. Though initially developed for the purification of recombinant proteins, this method has been extended to numerous other applications such as the specific immobilization of proteins on protein chips, the incorporation of active proteins in nanomaterials and on surfaces, the labeling of proteins with fluorophores, and the specific conjugation of biomolecules with proteins.