An extensive range of pigments including phycobiliproteins are present in algae. C-phycocyanin (C-PC), a phycobiliprotein, is one of the key pigments of Spirulina, a microalgae used in many countries as a dietary supplement. Algal pigments have massive commercial value as natural colorants in nutraceutical, cosmetics, and pharmaceutical industries, besides their health benefits. At present, inc...

A new bilin lyase gene cpcU was cloned from Arthrospira platensis FACHB314 to study the assembly of the phycocyanin β-Subunit. Two recombinant plasmids, one contained the phycocyanobilin (PCB) producing genes (hoxI and pcyA), while the other contained the gene of the β-Subunit of phycobiliprotein (cpcB) and the lyase gene (cpcU, cpcS, or cpcU/S) were constructed and separately transferred into ...

The crystal structure of R-phycocyanin from Polysiphonia urceolata (R-PC-PU) at 2.4 A is reported. The R-PC-PU crystal belongs to space group P4(3)2(1)2 with cell parameters a = 135.1 A, c = 210.0 A, and alpha = beta = gamma = 90 degrees. The structure was determined by molecular replacement. The crystallographic R-factor of the refined model is 0.189 (R(free) = 0.239). Comparison of the microe...

The limited knowledge we have about red algal genomes comes from the highly specialized extremophiles, Cyanidiophyceae. Here, we describe the first genome sequence from a mesophilic, unicellular red alga, Porphyridium purpureum. The 8,355 predicted genes in P. purpureum, hundreds of which are likely to be implicated in a history of horizontal gene transfer, reside in a genome of 19.7 Mbp with 2...

The bilin prosthetic groups of the phytochrome photoreceptors and the light-harvesting phycobiliprotein antennae arise from the oxygen-dependent ring opening of heme. Two ferredoxin-dependent enzymes contribute to this conversion: a heme oxygenase and a bilin reductase with discrete double-bond specificity. Using a dual plasmid system, one expressing a truncated cyanobacterial apophytochrome 1,...

Phycoerythrin, a photosynthetic accessory pigment, was isolated from Porphyridium cruentum and examined by electron microscopy and disc gel electrophoresis. The absorption monomer, with maxima at 563, 545, and a shoulder at 500 nm, has a molecular weight of about 300,000. With phosphotungstic acid staining it appears as a tightly structured disc-shaped particle possessing a mean diameter of 101...