Linked Life Data

1316181

Source:http://linkedlifedata.com/resource/pubmed/id/1316181

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1992-6-18
pubmed:abstractText
The saturation transfer electron spin resonance (STESR) spectra of 10 different positional isomers of phosphatidylcholine spin-labeled in the sn-2 chain have been investigated in the low temperature phases of dipalmitoyl phosphatidylcholine (DPPC) bilayers. The results of continuous wave saturation and of saturation recovery measurements on the conventional ESR spectra were used to define the saturation properties necessary for interpreting the STESR results in terms of the chain dynamics. Spin labels with the nitroxide group located in the center of the chain tended to segregate preferentially from the DPPC host lipids in the more ordered phases, causing spin-spin interactions which produced spectral broadening and had a very pronounced effect on the saturation characteristics of the labels. This was accompanied by a large decrease in the STESR spectral intensities and diagnostic line height ratios relative to those of spin labels that exhibited a higher degree of saturation at the same microwave power. The temperature dependence of the STESR spectra of the different spin label isomers revealed a sharp increase in the rate of rotation about the long axis of the lipid chains at approximately 25 degrees C, correlating with the pretransition of gel phase DPPC bilayers, and a progressive increase in the segmental motion towards the terminal methyl end of the chains in all phases. Prolonged incubation at low temperatures led to an increase in the diagnostic STESR line height ratios in all regions of the spectrum, reflecting the decrease in chain mobility accompanying formation of the subgel phase. Continuous recording of the central diagnostic peak height of the STESR spectra while scanning the temperature revealed a discontinuity at approximately 14-17 degrees C, corresponding to the DPPC subtransition which occurred only on the initial upward temperature scan, in addition to the discontinuity at 29-31 degrees C corresponding to the pretransition which displayed hysteresis on the downward temperature scan.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-2166598, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-2539207, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-263690, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-3026503, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-3029766, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-492310, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-5541516, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6246929, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6248052, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6269609, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6283533, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6871183, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6895317, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6933546, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-6952236, http://linkedlifedata.com/resource/pubmed/commentcorrection/1316181-7150553
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-3495
pubmed:author
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
879-91
pubmed:dateRevised
2010-9-7
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Saturation transfer, continuous wave saturation, and saturation recovery electron spin resonance studies of chain-spin labeled phosphatidylcholines in the low temperature phases of dipalmitoyl phosphatidylcholine bilayers. Effects of rotational dynamics and spin-spin interactions.
pubmed:affiliation
Max-Planck-Institut für biophysikalische Chemie, Abteilung Spektroskopie, Göttingen, Germany.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't