Protein purification refers to a series of processes whose
intent is to isolate either one or a few proteins from a mixture. The
importance of this process is that it is needed in order to properly characterize
aspects of the protein in interest – its function, interactions with other
material, and its structure 1. Protein purification can be used to
separate proteins from non-proteins in a mixture or to separate proteins from
other proteins in a mixture. In this case, the process used for protein
purification was a resin column with the element Nickel bound in the middle of
the column to obtain only the proteins and remove non-protein elements of the
mixture. This would result in any substance without histidine, which is an ?-amino acid used for
protein biosynthesis
2, not binding to the Nickel and flowing through the column. In
order to remove the protein from the column, it would require another step in
protein purification that would have to bind even tighter to the histidine than
Nickel; this would be Imidazole, our elution buffer. Imidazole has its ring
structure incorporated into histidine and is therefore able to compete with it
for binding sites on Nickel, allowing this solution to elute the protein from
the column 3. In this experiment, the sample loaded into the
column was a green fluorescent protein (GFP) without a linker 3.