Linked Life Data

7947845

Source:http://linkedlifedata.com/resource/pubmed/id/7947845

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
1994-12-28
pubmed:abstractText
Using low-temperature time-resolved spectroscopy, we have directly observed thermal back reaction of metarhodopsin I (meta I) to lumirhodopsin (lumi) and that of metarhodopsin II (meta II) to meta I in chicken rhodopsin to demonstrate the presence of thermal equilibria among lumi, meta I, and meta II. The back reaction from meta I to lumi was observed when the rhodopsin sample irradiated at -35 degrees C was warmed to -20 degrees C, while that from meta II to meta I was observed when the sample irradiated at -10 degrees C was cooled to -20 degrees C. Thermodynamic parameters of lumi, meta I, and meta II were calculated from the equilibrium constants estimated by analyzing the spectra of the equilibrium states at temperatures ranging from -30 to -10 degrees C. The results showed that meta I has an enthalpy and an entropy considerably smaller than those of lumi and meta II, while the difference in thermodynamic parameters between lumi and meta II is not so large. These results suggest that meta I is a crucial stage of conversion of the light energy captured by the chromophore into restricted conformations of the chromophore and/or protein, from which a large conformational change of the protein starts to form meta II.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14351-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Direct observation of the thermal equilibria among lumirhodopsin, metarhodopsin I, and metarhodopsin II in chicken rhodopsin.
pubmed:affiliation
Department of Biophysics, Faculty of Science, Kyoto University, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't