Discrete breathers in protein structures

摘要: Recently, using a numerical surface cooling approach, we have shown that highly energetic discrete breathers (DBs) can form in the stiffest parts of nonlinear network models large protein structures. In present study, an analytical extend our previous results to low-energy as well smaller proteins. We confirm and further scrutinize striking site selectiveness energy localization presence spatial disorder. particular, find that, sheer consequence disorder, non-zero gap for exciting DB at given either exists or not. Remarkably, former case, gaps arise result impossibility small-amplitude modes first place. contrast, latter small subset linear edge acts accumulation points, whereby DBs be continued arbitrary energies, while unavoidably approaching one such normal modes. case mode seems peculiar, its dispersion relation being simple little system dependent. Concerning structure–dynamics relationship, regions structures where easily (zero gaps) are unfailingly most connected ones, also characterized by weak local clustering. systematic analysis on database enzyme reveals amino-acid residues involved catalysis tend located regions. This finding reinforces idea localized origin may play important biological role, e.g., providing ready channel storage and/or contributing lower barriers chemical reactions.