When diving into the literature for the 7-HCAR enzyme we discovered something shocking about its purification. 7-HCAR was previously unable to be purified through the use of a histidine tag. The inability to use histidine tag purification would introduce additional costs to enable our use of the protein. In an attempt to better understand the phenomena hindering the purification we ventured into electrostatics interaction modelling. The electrostatics modelling showed that due to charge differences between the core of the protein and the hist tag may cause unforeseen consequences. To address these consequences we sought to develop a new spacer that would be able to fight these forces.

Using the electrostatics interactions model we generated an “ideal” spacer that would be able to fold into such that it can be used for purification. Using a feedback loop of structural models and estimation a final spacer with the desired folding was developed. This spacer is now known as the ICARUS spacer. The ICARUS spacer has been successfully implemented for the purification of the 7-HCAR protein it was designed for. Along with its use with 7-HCAR ICARUS has been successfully used on the protein pheophytinase. Along with this structural models have indicated that it maintains the desired folding as well.