Strep-tag® and His-tag are both widely used tools for affinity purification via a peptide tag. Choosing an appropriate affinity chromatography system for simple and efficient protein purification is a common question.
When it comes to purity and versatility in applications, some differences between both systems are obvious. The infographic on the right shows not only the time saving way of Strep-tag® protein purification but also the main key features of the Strep-tag® system at a glance.
Strep-tag® performs better than His-tag in purification of mammalian-expressed proteins
In combination with high density mammalian protein expression, the His-tag system can lead to poor purification results, if conditions are not optimized. In order to achieve pure proteins for downstream applications from the coupling of the His-tag system and high density mammalian systems, further adjustments like dialysis of the supernatant, lower media:resin ratios or the use of strip-resistant nickel resins become necessary. Such adaptions require additional optimization time and effort, however, these challenges can be avoided by using the Strep-tag® system.