In the sequence Glu-Pro-Ile-Leu, which amino acid contains the N-terminal group?
A) proline
B) leucine
C) isoleucine
D) glutamic acid

Question

Quizplus · Accepted Answer

The N-terminus refers to the end of the polypeptide chain that has a free amino group (-NH2). In this sequence, Glutamic acid (Glu) is at the N-terminus because it has an amino group that has not yet reacted to form a peptide bond with the Proline residue. Therefore, the correct answer is D (Glutamic acid).

In the Sequence Glu-Pro-Ile-Leu, Which Amino Acid Contains the N-Terminal