Displacements from closed βI domains
| Conformation | Cα root mean square deviation | ||
| β1-α1 loop | α1 helix | α1′ helix | |
| Å | Å | Å | |
| Cocked β2 | 1.5 | 2.4 | 2.9 |
| Uncocked β2 | 1.2 | 0.9 | 0.6 |
| Intermediate β1 | 1.3 | 0.7 | 0.2 |
| Intermediate β3 | 1.9 | 1.5 | 1.5 |
| Intermediate state 6 β3 | 1.6 | 0.8 | 0.4 |
| Intermediate state 7 β3 | 1.6 | 3.5 | 1.3 |
| Final state 8 β3 | 2.1 | 4.4 | 3.8 |
| Open β3 | 2.1 | 4.3 | 4.0 |
| Conformation | Cα root mean square deviation | ||
| β1-α1 loop | α1 helix | α1′ helix | |
| Å | Å | Å | |
| Cocked β2 | 1.5 | 2.4 | 2.9 |
| Uncocked β2 | 1.2 | 0.9 | 0.6 |
| Intermediate β1 | 1.3 | 0.7 | 0.2 |
| Intermediate β3 | 1.9 | 1.5 | 1.5 |
| Intermediate state 6 β3 | 1.6 | 0.8 | 0.4 |
| Intermediate state 7 β3 | 1.6 | 3.5 | 1.3 |
| Final state 8 β3 | 2.1 | 4.4 | 3.8 |
| Open β3 | 2.1 | 4.3 | 4.0 |
β1, β2, and β3 βI domains were superimposed on their closed counterparts. Differences in position were determined for β2 residues Y115–M117 (β1-α1 loop), D120–V124 (α1 helix), and G128–I138 (α1′ helix) and their equivalents in other β subunits. Structures use the following PDB ID numbers: intermediate β1 (3VI4) and its closed counterpart (3VI3); intermediate β3 (1L5G) and its closed counterpart (1JV2); β3 intermediate state 6 (3ZE2; chain B), state 7 (3ZDZ; chain B), final state 8 (3ZE2; chain D), and open β3 (2VDR) and their closed counterpart (3T3P).