ACID-UNFOLDING OF APOMYOGLOBIN

Conjectured pathway of apomyogobin folding

The simulated unfolding trajectory has at least four common points with the experemental re-folding pathway: the compeletly acid-ufolded state, the early kinetic intermediate (compact core involving helices AHG), late intermediate (compact core involving helices AHGB), and, of course, the native state. The predicted and measured average characteristics of these states, such as radius of gyration, helical content, etc. are very close. Experimentally is also known that the equilibrium molten globule I-state and the late re-folding intermediate are the same. These facts lead us to conjecture that the folding pathway of apomyoglobin may look like its acid-unfolding trajectory, going backwards in time.

Apomyoglobin folding pathway. Movie

Helical regions A,B,...H are represented by colors from red to violet.