For some recombinant proteins, purification characteristics on Strep-Tactin® MarcoPrep® differ from those on Strep-Tactin® Sepharose®
The Coomassie stained SDS gel shows the purification of a recombinant protein which exhibits exceptionally high non-specific protein binding. In this case, we have been able to remove the contaminants nearly quantitatively using the Strep-Tactin® MacroPrep® resin while the contaminants co-eluted with the recombinant protein after the same purification protocol using the Strep-Tactin® Sepharose® resin. (Please note: normally behaving recombinant proteins can be purified in a single step to homogeneity using Strep-Tactin® Sepharose®). This example shows that it may be reasonable to change the resin if non-specific protein binding occurs.
MacroPrep® is particularly advantageous, e.g. for plant proteins, where purification with MacroPrep® leads to better protein yields