Disease relevance of CYB_0575

• A terminal energy acceptor of the phycobilisome: the 75,000-dalton polypeptide of Synechococcus 6301 phycobilisomes--a new biliprotein [1].
• In cyanobacteria, light energy is mainly harvested by the phycobiliproteins that form the phycobilisome rods, and funneled to the photosynthetic reaction centers through the core components [2].
• Differences in the absorption properties and cellular costs between chlorophyll a(2)/b(2) and phycobilisome antennas in extant Prochlorococcus and Synechococcus appear to play a role in differentiating their ecological niches in the ocean environment [3].
• The linker and anchor subunits from the morphologically different phycobilisome of Synechocystis sp. strain PCC6714 were also shown to be concanavalin A reactive [4].
• Phycobilisome degradation is an ordered proteolytic process, visible by a color change of the cyanobacterial cell from blue-green to yellow-green (chlorosis) [5].

High impact information on CYB_0575

• 3) Changing the lipid composition of the thylakoid membrane has a dramatic effect on phycobilisome mobility [6].
• Diffusion of phycobilisomes on the thylakoid membranes of the cyanobacterium Synechococcus 7942. Effects of phycobilisome size, temperature, and membrane lipid composition [6].
• Rod structure of a phycoerythrin II-containing phycobilisome. I. Organization and sequence of the gene cluster encoding the major phycobiliprotein rod components in the genome of marine Synechococcus sp. WH8020 [7].
• Degradation of the cyanobacterial light harvesting complex, the phycobilisome, is a general acclimation response occurring under various stress conditions [8].
• The structure of the phycocyanin operons of the phycobilisome mutant strains AN112 and AN135 was compared to that of wild-type Synechococcus 6301 [9].

Biological context of CYB_0575

• The results support the conclusion that the site-specific methylation of phycobiliproteins contributes significantly to the efficiency of directional energy transfer in the phycobilisome [10].
• We suggest that this iron stress-induced glycoprotein is associated with the glycogen deposits on the thylakoid surface and that the glycosylation of phycobilisome linker and anchor subunits is involved in the physiological regulation of phycobilisome assembly and degradation [4].
• Our results contradict proposed models for the state transition, which require phosphorylation of, and an active role for, the phycobilisome [11].

Associations of CYB_0575 with chemical compounds

• Four phycobilisome-associated proteins were found to be specifically reactive with the lectin concanavalin A after subunits of isolated Anacystis nidulans R 2 phycobilisomes were separated on polyacrylamide gels and transferred onto nitrocellulose [12].
• Chemical analysis of the total isolated phycobilisome material indicated the presence of glucose (approx. 1.5% by wt) and N-acetylgalactosamine (0.15% by wt), consistent with our proposal that the concanavalin A-reactive polypeptides contain covalently linked, glucose-containing polysaccharides [12].
• Phycobilisome polypeptides separated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate were subjected to various glycoprotein-specific staining procedures [13].
• Structurally, the linker polypeptide should disrupt the C3 symmetry in the central cavity of the associated phycobiliprotein and this asymmetric interaction should serve to guide the transfer of excitation energy along PBS rods toward the core elements [14].

Analytical, diagnostic and therapeutic context of CYB_0575

• Spectroscopic studies that phycocyanin is in the hexamer form, (alpha beta)6, in intact phycobilisomes, and that the circular dichroism and absorbance of this aggregate are little affected by incorporation into the phycobilisome structure [15].
• Southern blot analysis showed that the genetic organization of the phycobilisome rod operon is very similar in the two strains [16].

References