Discrete breathers in protein structures Export

@article{citeulike:2745050, abstract = {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 of large protein structures. In the present study, using an analytical approach, we extend our previous results to low-energy discrete breathers as well as to smaller proteins. We confirm and further scrutinize the striking site selectiveness of energy localization in the presence of spatial disorder. In particular, we find that, as a sheer consequence of disorder, a non-zero energy gap for exciting a DB at a given site either exists or not. Remarkably, in the former case, the gaps arise as a result of the impossibility of exciting small-amplitude modes in the first place. In contrast, in the latter case, a small subset of linear edge modes acts as accumulation points, whereby DBs can be continued to arbitrary small energies, while unavoidably approaching one of such normal modes. In particular, the case of the edge mode seems peculiar, its dispersion relation being simple and little system dependent. Concerning the structure-dynamics relationship, we find that the regions of protein structures where DBs form easily (zero or small gaps) are unfailingly the most highly connected ones, also characterized by weak local clustering. Remarkably, a systematic analysis on a large database of enzyme structures reveals that amino-acid residues involved in catalysis tend to be located in such regions. This finding reinforces the idea that localized modes of nonlinear origin may play an important biological role, e.g., by providing a ready channel for energy storage and/or contributing to lower energy barriers of chemical reactions.}, author = {Piazza, Francesco and Sanejouand, Yves-Henri}, citeulike-article-id = {2745050}, citeulike-linkout-0 = {http://dx.doi.org/10.1088/1478-3975/5/2/026001}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/18451466}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=18451466}, day = {21}, doi = {10.1088/1478-3975/5/2/026001}, issn = {1478-3975}, journal = {Physical Biology}, keywords = {active\_site, allostery, discrete\_breathers, gnm, networks}, month = {June}, number = {2}, pages = {026001+}, posted-at = {2009-09-17 18:17:02}, priority = {2}, publisher = {Institute of Physics Publishing}, title = {Discrete breathers in protein structures}, url = {http://dx.doi.org/10.1088/1478-3975/5/2/026001}, volume = {5}, year = {2008} }

TY - JOUR ID - citeulike:2745050 L3 - citeulike-article-id:2745050 N2 - 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 of large protein structures. In the present study, using an analytical approach, we extend our previous results to low-energy discrete breathers as well as to smaller proteins. We confirm and further scrutinize the striking site selectiveness of energy localization in the presence of spatial disorder. In particular, we find that, as a sheer consequence of disorder, a non-zero energy gap for exciting a DB at a given site either exists or not. Remarkably, in the former case, the gaps arise as a result of the impossibility of exciting small-amplitude modes in the first place. In contrast, in the latter case, a small subset of linear edge modes acts as accumulation points, whereby DBs can be continued to arbitrary small energies, while unavoidably approaching one of such normal modes. In particular, the case of the edge mode seems peculiar, its dispersion relation being simple and little system dependent. Concerning the structure-dynamics relationship, we find that the regions of protein structures where DBs form easily (zero or small gaps) are unfailingly the most highly connected ones, also characterized by weak local clustering. Remarkably, a systematic analysis on a large database of enzyme structures reveals that amino-acid residues involved in catalysis tend to be located in such regions. This finding reinforces the idea that localized modes of nonlinear origin may play an important biological role, e.g., by providing a ready channel for energy storage and/or contributing to lower energy barriers of chemical reactions. IS - 2 JF - Physical Biology SN - 1478-3975 TI - Discrete breathers in protein structures PB - Institute of Physics Publishing VL - 5 SP - 026001 KW - active_site KW - allostery KW - discrete_breathers KW - gnm KW - networks AU - Piazza, Francesco AU - Sanejouand, Yves-Henri PY - 2008/06/21/ UR - http://dx.doi.org/10.1088/1478-3975/5/2/026001 ER -