Methods for the isolation of functional photosystem II core particles from the cyanobacterium Synechocystis sp. PCC 6803.

This chapter contains the description of several methods used for the isolation of functional photosystem II (PS II) core particles from wild type, photosystem I-less, and CP47 histidine-tagged cells of the cyanobacterium Synechocystis sp. PCC 6803. The presented protocols cover cultivation of photosystem I-containing and photosystem I-less cells, isolation of thylakoid membranes, purification of PS II core particles using a weak cation exchange or metal affinity column chromatography, and characterization of the final preparation.

Phycobilin/chlorophyll excitation equilibration upon carotenoid-induced non-photochemical fluorescence quenching in phycobilisomes of the cyanobacterium Synechocystis sp. PCC 6803.

To determine the mechanism of carotenoid-sensitized non-photochemical quenching in cyanobacteria, the kinetics of blue-light-induced quenching and fluorescence spectra were studied in the wild type and mutants of Synechocystis sp. PCC 6803 grown with or without iron. The blue-light-induced quenching was observed in the wild type as well as in mutants lacking PS II or IsiA confirming that neither IsiA nor PS II is required for carotenoid-triggered fluorescence quenching.

Isolation of functional photosystem II core particles from the Cyanobacterium synechocystis sp. PCC 6803.

This chapter contains the description of several methods used for the isolation of functional photosystem (PS)II core particles from wild-type (wt), PSI-less, and CP47 histidine-tagged cells of the cyanobacterium Synechocystis sp. PCC 6803. These protocols discuss the cultivation of PSI-containing and PSI-less cells, isolation of thylakoid membranes, purification of PSII core particles using a weak cation exchange or metal affinity column chromatography, and characterization of the final preparation.

Regulation of the tetrapyrrole biosynthetic pathway leading to heme and chlorophyll in plants and cyanobacteria.

Photosynthetic organisms synthesize chlorophylls, hemes, and bilin pigments via a common tetrapyrrole biosynthetic pathway. This review summarizes current knowledge about the regulation of this pathway in plants, algae, and cyanobacteria. Particular emphasis is placed on the regulation of glutamate-1-semialdehyde formation and on the channelling of protoporphyrin IX into the heme and chlorophyll branches.