Light-harvesting systems of brown algae and diatoms. Isolation and characterization of chlorophyll a/c and chlorophyll a/fucoxanthin pigment-protein complexes.
The present study examined the protein associations and energy transfer characteristics of chlorophyll c and fucoxanthin which are the major light-harvesting pigments in the brown and diatomaceous algae. It was demonstrated that sodium dodecyl sulfate (SDS)-solubilized photosynthetic membranes of these species when subjected to SDS polyacrylamide gel electrophoresis yielded three spectrally distinct pigment-protein complexes. The slowest migrating zone was identical to complex I, the SDS-altered form of the P-700 chlorophyll a-protein. The zone of intermediate mobility contained chlorophyll c and chlorophyll a in a molar ratio of 2 : 1, possessed no fucoxanthin, and showed efficient energy transfer from chlorophyll c to chlorophyll a. The fastest migrating pigment-protein zone contained fucoxanthin and chlorophyll a, possessed no chlorophyll c, and showed efficient energy transfer from fucoxanthin to chlorophyll a. It is demonstrated that the chlorophyll a/c-protein and the chlorophyll a/fucoxanthin-protein complexes are common to the brown algae and diatoms examined, and likely share similar roles in the photosynthetic units of these species.
D002338:Carotenoids / Q000031:analogs & derivatives* / Q000378:metabolism; D002734:Chlorophyll / Q000302:isolation & purification*; D003580:Cytochromes / Q000302:isolation & purification*; D004591:Electrophoresis, Polyacrylamide Gel; D056890:Eukaryota / Q000378:metabolism*; D008027:Light; D045342:Light-Harvesting Protein Complexes; D000459:Phaeophyceae / Q000378:metabolism*; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins / Q000302:isolation & purification*; D013045:Species Specificity; D013053:Spectrophotometry; D024341:Xanthophylls
D003580:Cytochromes; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D010940:Plant Proteins; D024341:Xanthophylls; C025164:fucoxanthin; D002734:Chlorophyll; D002338:Carotenoids