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. 2023 Jul;22(7):1561-1572.
doi: 10.1007/s43630-023-00397-2. Epub 2023 Mar 1.

The organization of the phycobilisome-photosystem I supercomplex depends on the ratio between two different phycobilisome linker proteins

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The organization of the phycobilisome-photosystem I supercomplex depends on the ratio between two different phycobilisome linker proteins

Mai Watanabe et al. Photochem Photobiol Sci. 2023 Jul.

Abstract

The phycobilisome (PBS) is an antenna protein complex in cyanobacteria, Glaucocystophytes, and red algae. In the standard PBS, the rod-core PBS, the rods are connected to the core by the rod-core linker protein CpcG. The rod-core PBS transfers the light energy mainly to photosystem (PS) II and to a lesser extent to PSI. Cyanobacteria assemble another type of PBS, the CpcL-PBS, which consists of only one rod. This rod-type PBS is connected to the thylakoid membrane by the linker protein CpcL and is a PSI-specific antenna. In the filamentous heterocyst-forming cyanobacterium Anabaena (Nostoc) sp. PCC 7120, the CpcL-PBS forms a complex with the tetrameric PSI (PBS-PSI supercomplex). The CpcL-PBS and the rod part of the rod-core PBS are identical except for the linker proteins CpcL and CpcG. How cells control the accumulation of the two different types of PBS is unknown. Here, we analyzed two mutant strains which either lack the major rod-core linker CpcG4 or overexpress the rod-membrane linker CpcL. In both mutant strains, more and larger PBS-PSI supercomplexes accumulated compared to the wild type. Our results suggest that CpcL and CpcG4 compete for the same phycobiliprotein pool, and therefore the CpcL/CpcG4 ratio determines the levels of PBS-PSI supercomplexes. We propose that the CpcL-PBS and the rod-core PBS fulfill distinct functions in light harvesting.

Keywords: CpcL-phycobilisome; Linker protein; Photosystem I-specific antenna; Phycobilisome.

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References

    1. Bryant, D. A., & Canniffe, D. P. (2018). How nature designs light-harvesting antenna systems: design principles and functional realization in chlorophototrophic prokaryotes. Journal of Physics B: Atomic, Molecular and Optical Physics, 51, 033001. https://doi.org/10.1088/1361-6455/aa9c3c - DOI
    1. Liu, L.-N., Chen, X.-L., Zhang, Y.-Z., & Zhou, B.-C. (2005). Characterization, structure and function of linker polypeptides in phycobilisomes of cyanobacteria and red algae: An overview. Biochimica et Biophysica Acta, 1708, 10. https://doi.org/10.1016/j.bbabio.2005.04.001 - DOI
    1. Watanabe, M., & Ikeuchi, M. (2013). Phycobilisome: architecture of a light-harvesting supercomplex. Photosynthesis Research, 12, 265–276. - DOI
    1. Adir, N. (2005). Elucidation of the molecular structures of components of the phycobilisome: Reconstructing a giant. Photosynthesis Research, 85, 15–32. https://doi.org/10.1007/s11120-004-2143-y - DOI - PubMed
    1. Liu, L.-N., Chen, X.-L., Zhang, X.-Y., Zhang, Y.-Z., & Zhou, B.-C. (2005). One-step chromatography method for efficient separation and purification of R-phycoerythrin from Polysiphonia urceolata. Journal of Biotechnology, 116, 91–100. https://doi.org/10.1016/j.jbiotec.2004.09.017 - DOI - PubMed

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