Linked Life Data

16218623

Source:http://linkedlifedata.com/resource/pubmed/id/16218623

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
41
pubmed:dateCreated
2005-10-12
pubmed:abstractText
Photochemically induced dynamic nuclear polarization (photo-CIDNP) is observed in frozen and quinone depleted photosynthetic reaction centers of the purple bacteria Rhodobacter sphaeroides wild type (WT) by (13)C solid-state NMR at three different magnetic fields. All light-induced signals appear to be emissive at all three fields. At 4.7 T (200 MHz proton frequency), the strongest enhancement of NMR signals is observed, which is more than 10 000 above the Boltzmann polarization. At higher fields, the enhancement factor decreases. At 17.6 T, the enhancement factor is about 60. The field dependence of the enhancement appears to be the same for all nuclei. The observed field dependence is in line with simulations that assume two competing mechanisms of polarization transfer from electrons to nuclei, three-spin mixing (TSM) and differential decay (DD). These simulations indicate a ratio of the electron spin density on the special pair cofactors is 3:2 in favor of the L-BChl during the radical cation state. The good agreement of simulations with the experiments raises expectations that artificial solid reaction centers can be tuned to show photo-CIDNP in the near future.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-7863
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
127
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14290-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Magnetic field dependence of photo-CIDNP MAS NMR on photosynthetic reaction centers of Rhodobacter sphaeroides WT.
pubmed:affiliation
Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't