  Covariance matrices of amino acid displacements, commonly used to
characterize the large-scale movements of proteins, are investigated through
the prism of Random Matrix Theory. Bulk universality is detected in the local
spacing statistics of noise-dressed eigenmodes, which is well described by a
Brody distribution with parameter $\beta\simeq 0.8$. This finding, supported by
other consistent indicators, implies a novel quantitative criterion to single
out the collective degrees of freedom of the protein from the majority of
high-energy, localized vibrations.
