Purification of the N-HEAT_81-1643_Additional Heparin step

Previously, I purified the HTT N-HEAT_81-1643 domain and showed that the HTT N-HEAT_81-1643 domain also elutes early from a Superose 6 column 10/300 (https://zenodo.org/record/3462496#.XY4limYpA2x). One hypothesis we proposed that could explain the early elution volume is that the construct HTT N-HEAT_81-1643 forms a complex with nucleic acid material.  Here we added an additional purification step with heparin resin to remove nucleic acid material from the sample. This strategy was successful for full length HTT+HAP40 samples in removing nucleic acid and other impurities from the samples (https://zenodo.org/record/2628064#.XYTL7WYpDcs) (performed by Dr. Rachel Harding).

Purified HTT N-HEAT_81-1643 domain sample was used to perform a buffer screen and biophysical characterization with DSLS, DSF and DLS.