Symmetry matters for the electronic structure of core complexes from Rhodopseudomonas palustris and Rhodobacter sphaeroides PufX-.
Low-temperature (1.4 K), single-molecule fluorescence-excitation spectra have been recorded for individual reaction center-light-harvesting 1 complexes from Rhodopseudomonas palustris and the PufX(-) strain of Rhodobacter sphaeroides. More than 80% of the complexes from Rb. sphaeroides show only broad absorption bands, whereas nearly all of the complexes from Rps. palustris also have a narrow line at the low-energy end of their spectrum. We describe how the presence of this narrow feature indicates the presence of a gap in the electronic structure of the light-harvesting 1 complex from Rps. palustris, which provides strong support for the physical gap that was previously modeled in its x-ray crystal structure.
Richter
M F
MF
Experimental Physics IV and Bayreuth Institute of Macromolecular Research, University of Bayreuth, D-95440 Bayreuth, Germany.
Baier
J
J
Prem
T
T
Oellerich
S
S
Francia
F
F
Venturoli
G
G
Oesterhelt
D
D
Southall
J
J
Cogdell
R J
RJ
Köhler
J
J
D001426:Bacterial Proteins / Q000737:chemistry*; D045342:Light-Harvesting Protein Complexes / Q000737:chemistry*; D012242:Rhodobacter sphaeroides / Q000737:chemistry*; D012241:Rhodopseudomonas / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; C088749:PufX protein, Rhodobacter