Difference between revisions of "Part:BBa K243022"

Revision as of 19:52, 21 October 2009

DsbA-Strep-DigA-Split Linker-Fok_a

This combination uses the benefits of an Streptavidin-tag for purification. It is also linked with a DigoxigenineA-tag DigA. The Split Linker connects the parts and adds additional space between them to guarantee the independent function of DigA-tag and the protein domain Fok_a.The DsbA tag is used to transfer the produced protein into the periplasm.

Usage and Biology

We applied the Streptavidine-tag to enable a simultaneous purification of constructs with a His-tag. Strep-tag shows also a higher affinity towards Strep-Tactin than His-tag. For that the purification with Strep-tag is more specific. The used DigoxigeninA-tag allows the coupling to an flurescein linked oligo. Emanating from our 3D modeling this combination of DigA tagged oligos and the construct containing the protein domain Fok_a is more efficiently than the use of a combination of DigA tagged oligos with a construct containing Fok_i. To avoid interactions between the DigA-tag with the connected protein domain Fok_a we applied the Split Linker. The Linker itself has no influence of the connected parts. We decided to use the Split Linker for this construct to get a longer distance between DigA-tag and Fok_a to guarantee the independent function of both parts. This Linker is an improved part of the team Freiburg08 and it is a suitable linker for fusion proteins. The properties of the split linker are an good compromise between the stability and the distance for the connection between protein domain Fok_a and the anticalin tag. The additional linkage of the construct wit DsbA allows the export of the protein into the periplasm. The accumulation of the expressed protein in the periplasm can be used for the purification of the protein.

Sequence and Features