Primary light harvesting system: phycobilisomes and associated membranes. Progress report, January 1, 1977--December 31, 1977

Technical Report · Sat Jan 01 04:00:00 EST 1977

OSTI ID:5340968

Gantt, E

Phycobilisomes attached to photosynthetic membranes function as the major light harvesting system in red and blue-green algae. It represents one of the most efficient energy transfer systems in photosynthetic organisms. Allophycocyanin is the terminal pigment in the transfer chain funnelling energy to chlorophyll in all intact phycobilisomes isolated from numerous algal species (Porphyridium cruentum, P. aerugineum, P. sordidum, Rhodosorus marinus, Griffithsia pacifica, Anacystis nidulans, Agmanellum quadruplicatum, Anabaena variabilis, Nostoc sp., Fremyella diplosiphon). Of the several forms of allophycocyanin which exist in dissociated phycobilisomes, the long wavelength form with a fluorescence emission of 675 nm (23/sup 0/C) and 685 (-196/sup 0/C) is considered to be the bridging pigment between the phycobilisome and chlorophyll. In Nostoc sp. this form comprises as much as 20 percent of the total allophycocyanin content. Some interconversion between allophycocyanin forms has been observed, which suggests that the same molecule can exist in various conformational or aggregational states. A medium was devised in which energetically active phycobilisome-photosynthetic vesicles were obtained. This is the first step necessary for effective recombination studies of phycobilisomes with membranes and for future exploration of the phycobilisome-membrane binding site.

• Research Organization: Smithsonian Institution, Rockville, Md. (USA). Radiation Biology Lab.
• DOE Contract Number: EY-76-S-05-4310
• OSTI ID: 5340968
• Report Number(s): ORO-4310-12
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ALGAE
BIOCHEMISTRY
BIOMASS
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CHEMICAL REACTIONS
CHEMISTRY
CHLOROPHYLL
ENERGY SOURCES
ENERGY TRANSFER
FLUORESCENCE
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
LUMINESCENCE
MEMBRANES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PHYCOCYANIN
PHYTOCHROMES
PIGMENTS
PLANTS
PORPHYRINS
RENEWABLE ENERGY SOURCES
SYNTHESIS