PureCube Cu-NTA Agarose
Immobilized metal affinity chromatography, or IMAC, has been employed for many applications making use of its versatile interaction with aromatic nitrogens and phosphates. To this end, NTA matrices have been loaded with a broad range of transition metals, as optimized for the individual interaction. Cu-NTA Agarose can be used for the purification of his-tagged proteins. It provides high yields of protein, at lower specificity than e.g. Ni- or Co-IMAC. Cu-NTA Agarose has also been used for the enrichment of copper-binding proteins, in particular with plant extracts (1).
PureCube Cu-NTA Agarose provides:
Enrichment of copper-binding proteins
Purification of his-tagged proteins with different specificity
Fig. 1: Affinity and specificity of metal ions commonly used for IMAC. Loading an IMAC resin with different metal ions can adjust the affinity and specificity to optimize the purity and yield of a purified protein.
Different metal ions confer different binding affinity and specificity
Loading different metal ions to a resin results in differing affinity and specificity for a his-tagged protein. Generally, cobalt exhibits the higest binding specificity of commonly used IMAC metal ions, leading to relatively low yields but high purity. Copper, at the other end of the spectrum, has a high affinity leading to high yields but unspecific binding. In searching for the optimal resin to purify a protein, it is recommended to explore different chelating ligands (IDA or NTA) and different metal ions.
1. Kung. C.C. et al. Proteomic survey of copper-binding proteins in Arabidopsis roots by immobilized metal affinity chromatography and mass spectrometry. Proteomics (2006), 6(9)2746-58.