X-ray crystal structures of the isolated phycobiliprotein components of the phycobilisome have provided high resolution details to the description of this light harvesting complex at different levels of complexity and detail. The linker-independent assembly of trimers into hexamers in crystal lattices of previously determined structures has been observed in almost all of the phycocyanin (PC) an...

Abstract Phycocyanin, a phycobiliprotein, is one of the few natural blue pigments available as food colourant, and it largely used in industry. We have devised an innovative two-step extraction process which allowed to obtain bright phycocyanin crude extracts with high purity grade P (within 2.5 3.5) directly from fresh biomass Arthrospira platensis Gomont 1892 (commonly named Spirulina). found...

Abstract Green seaweed, red and brown seaweed are the three main kinds of seaweeds, which also categorized as macroalgae. The color represents chemical compounds known photosynthetic pigments (biopigments) including carotenoids, chlorophylls, phycobiliproteins. This review is focused on biopigments, such phycoerythrin (PE), fucoxanthin (FX), siphonaxanthin (SX), their potential application ingr...

Phycocyanin is a phycobiliprotein involved in light harvesting and conduction of light to the reaction centers in cyanobacteria and red algae. The structure of C-phycocyanin from Gracilaria chilensis was solved by X-ray crystallography at 2.0 A resolution in space group P2(1). An interaction model between two PC heterohexamers was built, followed by molecular dynamic refinement. The best model ...

The algae, Oscillatoria, is commonly found in prawn ponds and can lead to reduced productivity. We examined metabolites of the bacteria Brevibacillus laterosporus for algicidal qualities. To determine the possible algicidal mechanisms of these bioactive metabolites, different amounts of sterile filtrate of bacterial suspensions were added to cultures containing Oscillatoria. The dry weight, the...

Differentiation of the filamentous cyanobacteria Calothrix sp strains PCC 7601 and PCC 7504 is regulated by light spectral quality. Vegetative filaments differentiate motile, gas-vacuolated hormogonia after transfer to fresh medium and incubation under red light. Hormogonia are transient and give rise to vegetative filaments, or to heterocystous filaments if fixed nitrogen is lacking. If incuba...

Phycobiliproteins carry linear tetrapyrrole chromophores (bilins) thioether-linked to specific cysteine residues. The process of bilin attachment to apoprotein in vivo has been characterized for only one bilin attachment site on one phycobiliprotein, that on the alpha subunit of phycocyanin (alpha PC). In the cyanobacterium Synechococcus sp. PCC 7002, the addition of phycocyanobilin to apo-alph...

A method for stably purifying a functional dye, phycocyanin from Spirulina platensis was developed by freezing and thawing method. Among various buffers used for phycocyanin yield efficiency sodium phosphate buffer (pH 7 and 0.1 M) was found to be most suitable for highest yield. During comparison of various buffers, sodium phosphate buffer was found as best buffer with 146 ±0.265 mg/g phycobil...

We report here the use of plasmonic metal nanostructures in the form of silver island films (SiFs) to enhance the fluorescence emission of five different phycobiliproteins. Our findings clearly show that the phycobiliproteins display up to a 9-fold increase in fluorescence emission intensity, with a maximum 7-fold decrease in lifetime when they are assembled as a monolayer above SiFs, as compar...

Phycocyanin (Pc) is a phycobiliprotein that has been recently reported to exhibit a variety of pharmacological properties. In this regard, antioxidant, anti-inflammatory, neuroprotective and hepatoprotective effects have been experimentally attributed to Pc. When it was evaluated as an antioxidant in vitro, it was able to scavenge alkoxyl, hydroxyl and peroxyl radicals and to react with peroxin...