These regions are folded, unfolded, Intermediate I (I 1 ), and Intermediate II (I 2 ). The folded region is defined as RMSD ≤ 0.20 nm, while the unfolded region is defined as RMSD ≥ 0.55 nm. I 1 is defined to be 0.20 nm ≤ RMSD ≤ 0.30 nm and 0.425 nm ≤ R g ≤ 0.525 nm while I 2 is defined to be 0.60 nm ≤ RMSD ≤ 0.70 nm and 0.70 nm ≤ R g ≤ 0.80 nm.