Proline [updated] May 2026

Proline can adopt both cis and trans conformations. The interconversion between these isomers is a slow process that often acts as a rate-limiting step in protein folding.

is one of the most distinctive of the 20 proteinogenic amino acids, characterized by its unique cyclic structure where the side chain is fused to the amino group, forming a secondary amine (often called an imino acid ). This structural rigidity allows proline to play critical roles in protein folding, collagen synthesis, and stress response across diverse biological kingdoms. Chemical and Structural Profile proline

Because of its role in collagen, proline is vital for skin repair and wound healing. 2. Plant Stress Tolerance Proline can adopt both cis and trans conformations