Protein purification simply describes a variety of methods available to isolate a specific protein from a cell extract, which is a mixture of proteins. The goal of this is to isolate the target protein, without deactivating it. Deactivating a protein means that it is no longer functional- sometimes this can be revived but other times it cannot. We will go into greater detail of each of these techniques, but below is a handy overview of what each technique accomplishes. Ultimately, as a protein becomes more pure, its activity should increase.
It is important to note that many times, these techniques will be used in combination- by starting with one method and then using others until the protein can be as pure as possible.
Corresponding posts in this series:
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