Question

A mutation causes Ala-26 in a protein’s sequence to be replaced by Leu-26. This makes the protein inactive and results in a disease. However, a double mutant occurs in some healthy people that still has Leu-26 but also contains a second mutation changing Phe-132 to Val-132 which allows the protein to regain its activity. Give a convincing explanation for why the double mutant regains activity. Use your knowledge of protein folding, NCI’s and protein secondary and tertiary structures in your answer. Explain whether you think it is an effect on secondary OR tertiary structure and why you favor one idea and why the other is ruled out!! You may use a picture if it helps your explanation.  

Answer 1