Table 1.

Identification of the PC and ANM modes that dominate experimentally observed conformational changes^a

^aPDB codes for 24 pairs of homologous NMR and X-ray structures are listed in the column ‘NMR/X-ray’. M and N are the available number of NMR models and the number of residues for a given protein respectively. Δ is the RMSD (Å) between the average NMR structure and the corresponding X-ray structure. The m_Pmax is the index of the PC mode that shows maximal correlation with Δ{Φ}, and α_P,max is the corresponding correlation (Equation 7 with k=m_Pmax). δ_PC is the cumulative contribution of all PC modes, δ_PC=(∑α_P,i²)^1/2(1≤i≤M). The δ_PC10 is the counterpart of δ_PC based on the first 10 modes (1≤i≤10). The m_Amax is the index of the ANM mode that shows the highest correlation with Δ{Φ}. The corresponding correlation is α_A,max. Bold-faced m_pmax/m_Amax values correspond to the 20 cases where robust modes describe most of observed conformational changes (see main text). δ_ANM is the ANM counterpart of δ_PC. The highest and second highest correlations observed between pairs of PC- and ANM-modes are α_PA1 and α_PA2 respectively. The corresponding pairs of mode numbers are m_PA1 and m_PA2, respectively.