Linked Life Data

18808201

Source:http://linkedlifedata.com/resource/pubmed/id/18808201

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2008-9-23
pubmed:abstractText
Valine 160 on beta-sheet-2 (S2) of mouse prion (moPrPC) has been previously identified as the most highly pH-sensitive site on moPrPC by ESR spectroscopy using site-directed spin labeling (SDSL) technique. However, no further theoretical analysis to reveal the molecular dynamics reported on the experimental ESR spectra is available. The X-band ESR spectra of R1 nitroxide spin label at V160 and four other sites are carefully analyzed over large pH and temperature ranges using a spectral simulation method based upon stochastic Liouville equation (SLE). The results clearly reveal the dynamics and ordering of the local environment of V160R1 showing that (i) molecular mobility of V160R1 on S2 gradually increases with a decrease of pH from 7.5 to 4.5; (ii) two distinctly different spectral components are simultaneously present in all spectra of V160R1 studied. The spectral components are, respectively, denoted as immobile (Im), characterized by lower molecular mobility and higher ordering, and mobile (Mb) component of high mobility and low ordering. The population ratio (Im/Mb) increases with increasing pH, while Im remains dominant in all V160R1 spectra. It suggests a more mobile and disordered dynamic molecular structure for mouse PrPC, which is very likely correlated with increased beta-sheet content at low pH, as the environment changes from neutral to acidic pH. Together with the results of the SLE-based analyses on the spectra of other sites that appear pH-insensitive, we suggest that the simultaneous presence of the spectral components for V160R1 is strongly correlated with the coexistence of multiple protein conformations in local structure of PrPC over the varied pH range. It demonstrates that the combined approach of the SDSL technique and the SLE-based analysis leads to a powerful method for unraveling the complexity of protein dynamics.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0739-1102
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
355-66
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Dynamics and local ordering of spin-labeled prion protein: an ESR simulation study of a highly PH-sensitive site.
pubmed:affiliation
Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan. ywchiang@mx.nthu.edu.tw
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't