Birmingham-based bioscience company, TriAltus (AL, USA) has announced the launch of a new activated immunity protein 7 (im7) affinity chromatography resin for the single-step cl7/im7 protein purification system. Compared with the original resin, the new resin increases the binding capacity from 15–20 mg/ml to 35–40 mg/ml.
The cl7/im7 protein purification system exploits the ultrahigh-affinity interaction between cl7 (the inactive variant of colicin E7 DNase) and its inhibitor, im7. The cl7 domain is tagged to the protein of interest, while the im7 inhibitor is covalently crosslinked to agarose beads.
By inserting the cl7 tag into the genes of eukaryotic or prokaryotic proteins, the cl7 tag can then be transferred to an expression vector or expressed in native cells. An engineered protease site then releases the target protein from the cl7 tag. Following the action of the protease, the cl7 tag can be removed from the column and the im7 chromatography resin reused.
TriAltus claim that, unlike most published purification processes for challenging proteins, this system enables one-step purification with high yield, high purity and high activity – reaching purity levels of 97–100%.
The new activated im7 chromatography resin has undergone proprietary chemical modifications that make it capable of binding to more im7 protein and concomitantly more cl7-tagged protein. Available in bulk and also packed into TriAltus gravity flow columns and fast protein liquid chromatography columns, the new resin aims to improve the efficiency of proteomics, interactomics and in vitro drug screening research.
Robert Shufflebarger, co-founder and CEO of TriAltus, explained: “Combined with our previously established affinity and salt loading advantages, the cl7/im7 system demonstrates clear superiority over His-tag and other commercial affinity tag systems. The result is the most efficient and universal tool available for simple, cost-effective, ultrahigh-affinity purification of complex proteins, which is essential for advanced structural and industrial applications as well as gene therapy research.”