|
rdf:type |
|
|
lifeskim:mentions |
umls-concept:C0035495,
umls-concept:C0037812,
umls-concept:C0181904,
umls-concept:C0282183,
umls-concept:C0332514,
umls-concept:C0596972,
umls-concept:C0728873,
umls-concept:C0812406,
umls-concept:C1167622,
umls-concept:C1521743,
umls-concept:C1704646,
umls-concept:C2755839
|
|
pubmed:issue |
23
|
|
pubmed:dateCreated |
1995-1-9
|
|
pubmed:abstractText |
Using 1-, 2-, 3- and 4-13C site-specifically labelled ubiquinone-10, reconstituted at the QA site of Rhodobacter sphaeroides R26 reaction centres, the infra-red bands dominated by the 1- and 4-C = O vibration of QA are assigned in the QA(-)-QA difference spectra. The mode dominated by the 4-C = O vibration is drastically downshifted in the reaction centres as compared with its absorption frequency in free ubiquinone-10. In contrast, the mode dominated by the 1-C = O vibration absorbs at similar frequencies in the free and the bound forms. The frequency shift of the 4-C = O vibration is due to a large decrease in bond order and indicates a strong interaction with the protein microenvironment in the ground state. In the charge-separated state the mode dominated by the semiquinone 4-C = O vibration is characteristic of strong hydrogen bonding to the microenvironment, whereas the mode dominated by the 1-C = O vibration indicates a weaker interaction. The asymmetric binding of the 1- and 4-C = O groups to the protein might contribute to the factors governing different redox reactions of ubiquinone-10 at the QA site as compared with its reactions at the QB site.
|
|
pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-1081231,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-11607443,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-1610825,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-16453681,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-1736990,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-1879543,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-1899390,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-2036404,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-2194478,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-2365070,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-2676514,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-3054889,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-4409276,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-8161557,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-8298022,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-8464908,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-8485130,
http://linkedlifedata.com/resource/pubmed/commentcorrection/7988549-8490022
|
|
pubmed:language |
eng
|
|
pubmed:journal |
|
|
pubmed:citationSubset |
IM
|
|
pubmed:chemical |
|
|
pubmed:status |
MEDLINE
|
|
pubmed:month |
Dec
|
|
pubmed:issn |
0261-4189
|
|
pubmed:author |
|
|
pubmed:issnType |
Print
|
|
pubmed:day |
1
|
|
pubmed:volume |
13
|
|
pubmed:owner |
NLM
|
|
pubmed:authorsComplete |
Y
|
|
pubmed:pagination |
5523-30
|
|
pubmed:dateRevised |
2010-9-10
|
|
pubmed:meshHeading |
|
|
pubmed:year |
1994
|
|
pubmed:articleTitle |
Asymmetric binding of the 1- and 4-C=O groups of QA in Rhodobacter sphaeroides R26 reaction centres monitored by Fourier transform infra-red spectroscopy using site-specific isotopically labelled ubiquinone-10.
|
|
pubmed:affiliation |
Institut für Biophysik, Ruhr-Universität Bochum.
|
|
pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|
