What are the features and benefits of the QIAexpress 6xHis Tag System?
FEATURES | BENEFITS |
The interaction of the 6xHis tag with Ni-NTA matrices is conformation independent | One-step purification can be carried out under native or denaturing conditions |
Mild elution conditions can be used | Binding, washing, and elution are highly reproducible, and have no effect on protein structure. Pure protein products are ready for direct use in downstream applications |
The 6xHis tag is much smaller than other commonly used tags | 6xHis tags can be used in any expression system. The Tag does not interfere with the structure and function of the recombinant protein |
The 6xHis tag is uncharged at physiological pH | The 6xHis tag does not interfere with secretion |
The 6xHis tag is poorly immunogenic | The recombinant protein can be used without prior removal of the tag as an antigen to generate antibodies against the protein of interest |
Using Factor Xa Protease, 6xHis tag can be easily and efficiently removed | The detagged protein can be used for crystallographical or NMR studies where removal of the 6xHis tag may be preferred |
Some QIAexpress vectors feature a 6xHis-dihydrofolate reductase tag (6xHis-DHFR tag) | Small peptides fused to the 6xHis DHFR tag are stabilized while being expressed. The 6xHis-DHFR tag is not highly immunogenic in mouse and rat, so that peptides fused to the tag can be used directly for immunizations or epitope mapping |