Fig. 3.
Tensor analysis of individual domains. (A) Trends of measured angles on the small subunit for this study (connected points), those obtained by Fu et al. (32) (NR, IRS1, IRS2, RS) and those by X-ray crystallography (PDB codes indicated). The values plotted, b/pl, Htilt, Hoc, and Hsw, are as defined in Tables S2 and S3. (B) Progression of the L1 stalk closing. (L1α and L1β correspond to the same angle in an oblique plane). (C, D, E) Progression of tRNA and L1 movements. (F) Free-energy landscape along the intersubunit rotation coordinate, computed from occupancies of states in equilibrium. The numbers describe the relative stabilities of the various ground states. Dotted line represents the largely unknown topology of the energy landscape between the sample points obtained by cryo-EM. It includes a peak at 20 kcal/mol, going off scale in our diagram, indicating the barrier separating MS I and MS II as calculated from tRNA-tRNA smFRET measurements.