Chromatography is frequently used to purify proteins from ce…

Chromatography is frequently used to purify proteins from cellular extracts. Scientists can use various strategies, depending on the tools and reagents available. You are interested in isolating additional proteins that interact with your protein target, but your lab mates have used all the purified protein stocks.   What are the limitations to the method you described in part B that would not be a concern if you could use the purified protein directly?  

Attempting to define the protein domains of protein X, you t…

Attempting to define the protein domains of protein X, you treat it with a protease and use polyacrylamide gel electrophoresis to analyze the peptides produced. In the past, you have used chymotrypsin to perform this experiment, but the stock of this enzyme has been used up. You find a stock of elastase and decide to use it instead of waiting for a new stock of chymotrypsin to arrive.   Give two reasons why elastase is a good substitute for chymotrypsin in this assay.