Linked Life Data

20668739

Source:http://linkedlifedata.com/resource/pubmed/id/20668739

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
35
pubmed:dateCreated
2010-8-27
pubmed:abstractText
Two main onsets of anharmonicity are present in protein dynamics. Neutron scattering on protein hydrated powders revealed a first onset at about 150 K and a second one at about 230 K (the so called dynamical transition). In order to assess the molecular origin of protein anharmonicity, we study different homomeric polypeptides by incoherent elastic neutron scattering, thus disentangling the contribution of different molecular groups in proteins. We show that methyl group rotations are the main contributors to the low temperature onset. Concerning the dynamical transition, we show that it also occurs in absence of side chains; however, the presence and mobility of side chains substantially increases the fluctuations amplitude without influencing the transition temperature. We also investigate the role of hydration on the anharmonic contributions. Our study shows that methyl group rotations are unaffected by hydration and confirms that the dynamical transition is suppressed in dry samples. In hydrated samples, while the pure backbone contribution does not depend on the hydration h at h > or = 0.2, in the presence of side chains the anharmonic fluctuations involved in the dynamical transition are enhanced by increasing the water content.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1463-9084
pubmed:author
pubmed:issnType
Electronic
pubmed:day
21
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10215-20
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Molecular origin and hydration dependence of protein anharmonicity: an elastic neutron scattering study.
pubmed:affiliation
Department of Physical and Astronomical Sciences, University of Palermo, via Archirafi 36, I-90123, Palermo, Italy. giorgio.schiro@fisica.unipa.it
pubmed:publicationType
Journal Article