This system uses six tandem histidine
residues to tag proteins for detection and purification, but safely so
that neither their structure nor their function is altered. The tagged
proteins are immobilized on a resin that contains divalent nickel
cations. The proteins bind here because the 6x-His tag is attracted
to the nickel embedded within the resin.
This procedure lasts only two or three hours. It consists of four basic steps:
1. Prepare lysate containing 6x-His tagged protein
2. Add the lysate to the resin
3. Wash off any unbound lysate
4. Elute the 6x-His tagged protein
For a more elaborate description of this procedure click here and enter product name ProBondTM.
The XpressTM system is easier
and faster than other techniques for protein purification. Chromatography
techniques require up to two days to obtain results. With these techniques
detailed knowledge about the protein of interest's structure is required.
The XpressTM system only needs the 6x-His tag.