Figure 7. PCA Analysis of (𝛔2-𝛔4) - SnoaL2 correlated motions.PCA scatter plots (PC1 vs. PC2) representing the projections of the Cα displacements along the trajectory onto the first principal eigenvector, PC1 (x-axis), vs. the projections onto the second principal eigenvector, PC2 (y-axis), as derived from MD replicas of RpoE10 (A) wild-type, (B) Mut1, (C) Mut2(D) Del1 models. A larger subspace of B) RpoE10(Mut1) and D) RpoE10(Mut1) relative to the wild-type A) RpoE10 and B) RpoE10 (Mut2) suggested an association with the enhanced flexible behavior upon mutation in NPDKV or the deletion of the proximal SnoaL2 domain. E) Eigenvalues (variance) plotted against eigenvector indices constructed from PCA of the 200ns MD trajectories of backbone atoms for RpoE10 (a) wild-type, (b) Mut1, (c) Mut2 (d) Del1. The line represents the eigenvalues of the covariance matrix of the first 20 eigenvectors. The index with value 1 indicates the largest eigenvalue. An altered Eigenvalues shows the signals for critical transitions in the conformational changes of the protein. F, G, H and I: Essential dynamics analysis of Rpo10 and its mutant (Mut1 and Mut2. The superimposition of structural coordinates associated with the principal component 1 (PC1) of F) RpoE10 and mutant (RpoE10 (G) Mut1, H) Mut2 and I) Del1)) conformers are displaying global motion. The initial conformations are colored (σ2- red, σ4-blue, and SnoaL2- yellow), and the final and the intermediate ones are shown in grey. A circle marks the fluctuations in L3-loop connecting the α2 and α3. The orientations of correlated and anti-correlated motions are indicated with a red and blue double arrow at -10 promoter binding groove, respectively. The differential movement of motif residues was recorded with divergent displacements. The direction of displacement of the NPDKV (Cyan), DGGGR(Magenta), and WLPEP(Green) motifs are labeled and shown below the respective conformers (Magnitude is given in Supplemental Table S5). Red and Blue color balls represent initial and final conformation, respectively. The RpoE10 and its mutant forms are described in the tube model.