Abstract

This report involves the extraction, the purification and a general characterization of the phycobiliproteins present in the red algae Gracilaria chilensis (Bird, McLachlan y Oliveira). Three phycobiliproteins were purified, R-phycoerythrin (PE) (?max = 566 nm, 540 nm); phycocyanin (PC) (?max = 621 nm and 550 nm); and allophycocyanin (APC) (?max = 651 nm and a shoulder at 620 nm). The ? and ? structura subunits of each protein, have molecular weights 18 kD, 16 kD and 15 kD, respectively. A spectroscopic method to determine the amount of each type of phycobiliprotein in a mixture is proposed. This method was used to make a comparison among the phycobiliprotein composition in phycobilisomes isolated from pigmentation variants of the same specie (green, dark green and brown reddish). The molar ratio, APC: PC : PE was 10:4:2 for green variant, 10 : 3 : 6 for the dark green variant and 10 : 2 : 10 for the brown reddish variant.