Fluorescence of native and carotenoid-depleted LH2 from Chromatium minutissimum, originating from simultaneous two-photon absorption in the spectral range of the presumed (optically 'dark') S(1) state of carotenoids.
Native and carotenoid-depleted peripheral purple bacterial light-harvesting complex (LH2) were investigated by simultaneous two-photon excited (between 1300-1500 nm) fluorescence (TPF). TPF results from direct bacteriochlorophyll excitation in both samples. The spectral position of the 2A(g)(-) state of rhodopin [corrected] is indicated by a diminuition of the bacteriochlorophyll TPF in native LH2. In conclusion, comparison to carotenoid-depleted samples is a conditio sine qua non for unambiguous interpretation of similar experiments.
Krikunova
M
M
Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2a, D-12489 Berlin, Germany.
Kummrow
A
A
Voigt
B
B
Rini
M
M
Lokstein
H
H
Moskalenko
A
A
Scheer
H
H
Razjivin
A
A
Leupold
D
D
D001429:Bacteriochlorophylls / Q000737:chemistry; D002338:Carotenoids / Q000737:chemistry* / Q000302:isolation & purification; D002844:Chromatium / Q000737:chemistry*; D004735:Energy Transfer; D045342:Light-Harvesting Protein Complexes; D017785:Photons; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*; D012243:Rhodopsin / Q000737:chemistry; D013050:Spectrometry, Fluorescence
D001429:Bacteriochlorophylls; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D002338:Carotenoids; D012243:Rhodopsin