Linked Life Data

9711298

Source:http://linkedlifedata.com/resource/pubmed/id/9711298

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-9-3
pubmed:abstractText
Oxygen transport in thylakoid membranes of spinach chloroplasts (Spinacia oleracea) has been studied by observing the collisions of molecular oxygen with spin labels, using line broadening electron paramagnetic resonance (EPR) spectroscopy. Stearic acid spin labels were used to probe the local oxygen diffusion-concentration product. The free radical moiety was located at various distances from the membrane surface, and collision rates were estimated from linewidths of the EPR spectra measured in the presence and absence of molecular oxygen. The profile of the local oxygen diffusion-concentration product across the membrane determined at 20 degrees C demonstrates that this product, at all membrane locations, is higher than the value measured in water. From the profile of the oxygen diffusion-concentration product, the membrane oxygen permeability coefficient has been estimated using the procedure developed earlier (W.K. Subczynski, J.S. Hyde, A. Kusumi, Proc. Natl. Acad. Sci. USA 86 (1989) 4474-4478). At 20 degrees C, the oxygen permeability coefficient for the lipid portion of the thylakoid membrane was found to be 39.5 cm s-1. This value is 20% higher than the oxygen permeability coefficient of a water layer of the same thickness as the thylakoid membrane. The high permeability coefficient implies that the oxygen concentration difference across the thylakoid membrane generated under the illumination of the leaf by saturating actinic light is negligible, smaller than 1 microM.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
1365
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
453-63
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Oxygen permeability of thylakoid membranes: electron paramagnetic resonance spin labeling study.
pubmed:affiliation
Biophysics Department, Jagiellonian University, Krakow, Poland.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't