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arXiv · 1103.0706

Anharmonic transitions in nearly dry L-cysteine I

T. A. Lima·E. T. Sato·E. T. Martins·P. Homem-de-Mello·A. F. Lago·M. D. Coutinho-Neto·F. F. Ferreira·C. Giles·M. O. C. Pires·H. Martinho
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Abstract

Two special dynamical transitions of universal character have been recently observed in macromolecules at $T_{D}\sim 180 - 220$ K and $T^{*}\sim 100$ K. Despite their relevance, a complete understanding of the nature of these transitions and their consequences for the bio-activity of the macromolecule is still lacking. Our results and analysis concerning the temperature dependence of structural, vibrational and thermodynamical properties of the orthorhombic polymorph of the amino acid L-cysteine (at a hydration level of 3.5%) indicated that the two referred temperatures define the triggering of very simple and specific events that govern all the biochemical interactions of the biomolecule: activation of rigid rotors ($T T_{D}$).

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T. A. Lima, E. T. Sato, E. T. Martins, P. Homem-de-Mello, A. F. Lago, M. D. Coutinho-Neto, F. F. Ferreira, C. Giles, M. O. C. Pires, H. Martinho. 2011-03-03. Anharmonic transitions in nearly dry L-cysteine I. https://doi.org/10.1088/0953-8984%2F24%2F19%2F195104

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