Possible Explanation of Destabilization of Asn to Ala Mutants
| possible reasons | explanation | effect on mutant | support observed destab. of mutant? |
| residue conformational entropy | Ala in bigger hole: more freedom motion, favored entropically | stabilize mutant | opposite observed. |
|
free energy excess cavity formation |
energy penalty to make an unoccupied cavity approx. 0. 8 kcal/mol
|
destabilize |
support observed but not size of observed effect (2.9 kcal/mol |
| free energy change for protein conformational changes | rearrange protein to fill cavity | stabilize mutant | opposite observed |