Abstract:
:Orientation angles of five emitting dipoles of chlorophyll a in thylakoids were estimated from low temperature fluorescence polarization ratio spectra of magnetically oriented chloroplasts. A simple expression is given also for the evaluation of data from linear dichroism measurements. It is shown that the Qy dipoles of chlorophylls lie more in the plane of the membranes and span a larger angular interval than was previously thought. Values for the orientation factor are calculated using various models corresponding to different degrees of local order of the Qy dipoles of chlorophylls in the thylakoid. We show that the characteristic orientation pattern of the Qy dipoles of chlorophylls in the membrane, i.e., increasing dichroism toward longer wavelengths, may favour energy transfer between the antenna chlorophylls as well as funnel the excitation energy into the reaction centers.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Garab GI,Kiss JG,Mustárdy LA,Michel-Villaz Mdoi
10.1016/S0006-3495(81)84860-6subject
Has Abstractpub_date
1981-06-01 00:00:00pages
423-37issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(81)84860-6journal_volume
34pub_type
杂志文章abstract::An attempt was made to confirm previous reports of resonant-like dielectric absorption of plasmid DNA in aqueous solutions at 1-10 GHz. The dielectric properties of the sample were measured using an automatic network analyzer with two different techniques. One technique used an open-ended coaxial probe immersed in the...
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