申論題

1. A scientist uses the yeast expression system to over-express one recombinant protein, and which is also an enzyme. Based on the enzymatic activity of the recombinant protein, the scientist is able to purify the protein and makes the purification table. 

(5) When the protein is resolved on the sodium dodecył sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by Coomassie brilliant blue R250 (CBR) staining, only a protein band around 55 kDa is observed on the gel. Do you think the result match the predicted molecular weight of the protein from (4)? If not, please explain the possible reason for that. In addition, which experiment would confirm that?