Figure 4. Variation in <σXG> and <σNG> as a Function of the Number of Excluded GNM Slow Modes, Averaged over All 64 Protein Pairs.
The abscissa indicates the number of modes taken into consideration. N′ refers to the complete set of nonzero modes; N′ – k refers to all modes except the slowest k modes. Note that the differences in average correlation coefficients as a function of the number of included modes included are statistically significant, with the exception of that between the N and N – 1 values for σXG, verified by paired Student’s t test.
(A) Excluding the contribution of the slowest GNM mode does not decrease the correlation <σXG>, whereas additional removal of slow modes from the computations reduces the correlation with X-ray results.
(B) Excluding the slowest GNM modes significantly decreases the correlation <σNG> with the NMR rmsd data.
