My first exposure to visibly fluorescent proteins (FPs) was near the end of my time as a faculty member at the University of California, Berkeley. Professor Alexander Glazer, a friend and colleague there, was the world s expert on phycobiliproteins, the brilliantly colored and intensely fluorescent proteins that serve as light-harvesting antennae for the photosynthetic apparatus of blue-green a...

The morphology of the marine cyanobacterium DC-2 and two light-harvesting complexes from it have been characterized. DC-2 has an outer cell wall sheath not previously observed, the purified phycoerythrin shows many unusual properties that distinguish it from all phycoerythrins characterized to date, and isolated phycobilisomes have a single absorption band at 640 nm in the phycocyanin-allophyco...

DNA fragments encoding a red light-inducible phycocyanin gene and a green light-inducible phycoerythrin gene have been used to investigate the effect of red and green pulses on the accumulation of phycocyanin and phycoerythrin mRNA in subsequent darkness. A red pulse promotes phycocyanin and suppresses phycoerythrin mRNA accumulation while a green pulse has an opposite effect on both transcript...

The pathway for phycocyanobilin biosynthesis in Synechococcus sp. strain PCC 7002 comprises two enzymes: heme oxygenase and phycocyanobilin synthase (PcyA). The phycobilin content of cells can be modified by overexpressing genes encoding alternative enzymes for biliverdin reduction. Overexpression of the pebAB and HY2 genes, encoding alternative ferredoxin-dependent biliverdin reductases, cause...

Cyanobacteria produce phycobilisomes, which are macromolecular light-harvesting complexes mostly assembled from phycobiliproteins. Phycobiliprotein beta subunits contain a highly conserved gamma-N-methylasparagine residue, which results from the posttranslational modification of Asn71/72. Through comparative genomic analyses, we identified a gene, denoted cpcM, that (i) encodes a protein with s...

In dark-adapted plants and algae, chlorophyll a fluorescence induction peaks within 1s after irradiation due to well documented photochemical and non-photochemical processes. Here we show that the much slower fluorescence rise in cyanobacteria (the so-called "S to M rise" in tens of seconds) is due to state 2 to state 1 transition. This has been demonstrated in particular for Synechocystis PCC6...