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Updated: Jul 10, 2026

High Precision FRET at Single-molecule Level for Biomolecule Structure Determination
Published on: May 13, 2017
Spectral diffusion of the lowest exciton component in the core complex from Rhodopseudomonas palustris studied by
Martin F Richter1, Jürgen Baier, June Southall
1Experimental Physics IV and Bayreuth Institute of Macromolecular Research (BIMF), University of Bayreuth, 95440, Bayreuth, Germany.
Abstract:
We have recorded fluorescence-excitation spectra from individual RC-LH1 complexes from Rhodopseudomonas palustris. The spectra feature a few broad bands accompanied by a sharp line at the low-energy side of the spectrum which is ascribed to the lowest exciton state of the BChl a assembly. Recording several fluorescence-excitation spectra from the same individual complex in rapid succession reveals that the linewidth of the lowest exciton transition is determined by spectral diffusion which increases for higher excitation energies.
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