ABSTRACT
The phycobilisomes of the cyanobacteria and red algae are the sites of biliproteins. Tandeau de Marsac and Cohen-Bazire discovered several bands in sodium dodecyl sulfate gel electrophoresis experiments of phycobilisomes that do not correspond to the molecular weights of the biliprotein subunits. An UV mutant of this cyanobacterium was also defective in phycobilisome structure. The core and C-phycoerythrin rods appeared normal, but the rods did not attach to the cores. Phycoerythrocyanin was present in two cyanobacteria whose phycobilisomes have been studied, Anabaena variabilis and Mastigocladus laminosus. Phycoerythrocyanin has a higher energy absorption than C-phycocyanin and was therefore likely to function like phycoerythin by transferring excitation energy to C-phycocyanin. Chromatic adaptation has been used as mentioned above to study linker function in several cyanobacteria. Bryant et al. have used this technique to show that the variations in phycobilisome size and pigment composition were produced by variations in rod length and composition.
