Pigment compositions, spectral properties, and energy transfer efficiencies between the xanthophylls and chlorophylls in the major and minor pigment-protein complexes of photosystem II.
Absorption, fluorescence, and fluorescence excitation spectra have been measured from CP26, CP29, and monomeric and trimeric LHCIIb light-harvesting complexes isolated from Photosystem II subchloroplast particles from spinach. The complexes were purified using a combination of isoelectric focusing and sucrose gradient ultracentrifugation. The chlorophyll (Chl) and xanthophyll pigment compositions were measured using high-performance liquid chromatography (HPLC). Using the pigment compositions from the HPLC analysis as a starting point, the absorption spectral profiles of the complexes have been reconstructed from the individual absorption spectra obtained for each of the pigments. Also, the fluorescence excitation spectra of the complexes have been deconvoluted. The data reveal the energy transfer efficiencies between Chl b and Chl a and between specific xanthophylls and Chl a in the complexes. The spectral analyses reveal the underlying features of the highly congested spectral profiles associated with the complexes and are expected to be beneficial to researchers employing spectroscopic methods to investigate the mechanisms of energy transfer between the pigments bound in these complexes.
Das
Somes Kumar
SK
Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, USA.
Frank
Harry A
HA
D002734:Chlorophyll / Q000737:chemistry*; D000077194:Chlorophyll A; D061146:Chlorophyll Binding Proteins; D002851:Chromatography, High Pressure Liquid; D031541:Fluorescence Resonance Energy Transfer; D045342:Light-Harvesting Protein Complexes; D046911:Macromolecular Substances; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D018724:Spinacia oleracea; D024341:Xanthophylls / Q000737:chemistry*
C069660:CP29 light harvesting complex; D061146:Chlorophyll Binding Proteins; D045342:Light-Harvesting Protein Complexes; D046911:Macromolecular Substances; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D024341:Xanthophylls; D002734:Chlorophyll; C037184:chlorophyll b; D000077194:Chlorophyll A