His₆-fusion-tagged proteins can be recovered from affinity chromatography columns because the histidine tag tightly binds to beads coated with ________ ions. The elution buffer contains ________, which has stronger affinity for these ions.

Question

Quizplus · Accepted Answer

The histidine tag binds tightly to nickel ions, so nickel-coated beads can be used to capture the His₆-fusion-tagged protein. Imidazole has stronger affinity for nickel ions than histidine, so an elution buffer containing imidazole can be used to release the His₆-fusion-tagged protein from the nickel-coated beads.

His₆-Fusion-Tagged Proteins Can Be Recovered from Affinity Chromatography Columns Because