How do the pK_avalues of an ionizable side chain compare when the amino acid is free versus when it is in a polypeptide chain? A) The pK_aof the side chain is independent of whether the amino acid is in a polypeptide chain or is free. B) The pK_aof the side chain is always lower for the free amino acid. C) The pK_aof the side chain may be lower or higher in a polypeptide chain due to weaker inductive effects and differences in their microenvironments. D) The pK_aof the side chain is usually higher in a polypeptide chain due to stabilization from nearby residues in the three-dimensional structure.

Question

Quizplus · Accepted Answer

The pKa of an ionizable side chain can vary when the amino acid is part of a polypeptide chain due to changes in the local environment and interactions with nearby residues, which can either stabilize or destabilize the ionized form.

How Do the PKa values of an Ionizable Side Chain

How Do the PK_avalues of an Ionizable Side Chain