2024-03-29T00:09:39Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1363852020-05-21T11:04:14Zcom_10261_115com_10261_3col_10261_368
Dynamics of amorphous and partially crystallized proline solutions
Saiz, Luciana M.
Cerveny, Silvina
Eusko Jaurlaritza
Ministerio de Educación (España)
Dielectric spectroscopy
Proline
Amino acid
Water dynamics
Dynamics of water in the hydration shells of proteins in the no man's land temperature region is a currently debated topic. Previously [1], we proposed the use of lysine aqueous solutions as a model system to study the dynamics of water in a genuine biological solution at any temperature. We found that lysine can be completely dissolved in water without crystallization, making it possible to access the dynamics of amorphous water in a biological environment. By contrast, in this work we studied proline aqueous solutions, which partially crystallize upon cooling. We found similar results in the two systems: the presence of three water relaxations where the two slowest processes (processes 2 and 3) resemble the behavior of normal glasses. Moreover, we observed the change of a cooperative (α-like) water relaxation to a more local β-like water relaxation with decreasing temperature whereas a faster water relaxation process is also present. In addition, we studied amorphous samples in a restricted temperature interval, and also found three different dynamics (processes 3, 4 and 5). As in the case of the hydrated protein powders, the two faster dynamics (3 and 4) are coupled or slaved.
We acknowledge funding from the Basque Government (SAIOTEK Program No. S-PE13IV001 and ETORTEK program), and the Spanish Ministry of Education (project MAT2012-31088). LMS acknowledges the Bunge y Born Foundation.
Peer Reviewed
2016-09-06T09:38:38Z
2016-09-06T09:38:38Z
2015
2016-09-06T09:38:38Z
artículo
http://purl.org/coar/resource_type/c_6501
doi: 10.1016/j.jnoncrysol.2014.08.049
issn: 0022-3093
e-issn: 1873-4812
Journal of Non-Crystalline Solids 407: 486-493 (2015)
http://hdl.handle.net/10261/136385
10.1016/j.jnoncrysol.2014.08.049
http://dx.doi.org/10.13039/501100003086
Sí
none
Elsevier