Levinthal's paradox

Levinthal's paradox highlights that, if a protein randomly searched all possible shapes, it would take an astronomically long time to fold into its proper form—far longer than it actually does in nature. Yet, proteins fold quickly and reliably. This suggests that proteins don't search randomly; instead, they follow specific pathways guided by their chemistry and structure, enabling them to fold efficiently. The paradox emphasizes how biological systems are optimized to avoid endless trial-and-error, ensuring rapid and reliable formation of functional proteins.