{"doi":"10.1104/pp.111.192849","title":"Photosynthetic Pigment Localization and Thylakoid Membrane Morphology Are Altered in Synechocystis 6803 Phycobilisome Mutants\n \n ","abstract":"Abstract\n Cyanobacteria are oxygenic photosynthetic prokaryotes that are the progenitors of the chloroplasts of algae and plants. These organisms harvest light using large membrane-extrinsic phycobilisome antenna in addition to membrane-bound chlorophyll-containing proteins. Similar to eukaryotic photosynthetic organisms, cyanobacteria possess thylakoid membranes that house photosystem (PS) I and PSII, which drive the oxidation of water and the reduction of NADP+, respectively. While thylakoid morphology has been studied in some strains of cyanobacteria, the global distribution of PSI and PSII within the thylakoid membrane and the corresponding location of the light-harvesting phycobilisomes are not known in detail, and such information is required to understand the functioning of cyanobacterial photosynthesis on a larger scale. Here, we have addressed this question using a combination of electron microscopy and hyperspectral confocal fluorescence microscopy in wild-type Synechocystis species PCC 6803 and a series of mutants in which phycobilisomes are progressively truncated. We show that as the phycobilisome antenna is diminished, large-scale changes in thylakoid morphology are observed, accompanied by increased physical segregation of the two photosystems. Finally, we quantified the emission intensities originating from the two photosystems in vivo on a per cell basis to show that the PSI:PSII ratio is progressively decreased in the mutants. This results from both an increase in the amount of photosystem II and a decrease in the photosystem I concentration. We propose that these changes are an adaptive strategy that allows cells to balance the light absorption capabilities of photosystems I and II under light-limiting conditions.","journal":"Plant Physiology","year":2012,"id":674242,"datarank":0.637274286307404,"base_score":4.248495242049359,"endowment":4.248495242049359,"self_citation_contribution":0.637274286307404,"citation_network_contribution":0.0,"self_endowment_contribution":0.637274286307404,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":69,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1761617,"name":"Michelle Liberton","orcid":null,"position":1,"is_corresponding":false},{"id":1761619,"name":"Howland D.T. Jones","orcid":null,"position":2,"is_corresponding":false},{"id":1761622,"name":"Omar F. Garcia","orcid":null,"position":3,"is_corresponding":false},{"id":580490,"name":"Himadri B. Pakrasi","orcid":"0000-0001-8240-2123","position":4,"is_corresponding":false},{"id":1548705,"name":"Jerilyn A. Timlin","orcid":null,"position":5,"is_corresponding":false},{"id":1761616,"name":"Aaron M. Collins","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"resolved":true,"title":"Photosynthetic Pigment Localization and Thylakoid Membrane Morphology Are Altered in Synechocystis 6803 Phycobilisome Mutants\n \n ","abstract":"Abstract\n Cyanobacteria are oxygenic photosynthetic prokaryotes that are the progenitors of the chloroplasts of algae and plants. These organisms harvest light using large membrane-extrinsic phycobilisome antenna in addition to membrane-bound chlorophyll-containing proteins. Similar to eukaryotic photosynthetic organisms, cyanobacteria possess thylakoid membranes that house photosystem (PS) I and PSII, which drive the oxidation of water and the reduction of NADP+, respectively. While thylakoid morphology has been studied in some strains of cyanobacteria, the global distribution of PSI and PSII within the thylakoid membrane and the corresponding location of the light-harvesting phycobilisomes are not known in detail, and such information is required to understand the functioning of cyanobacterial photosynthesis on a larger scale. Here, we have addressed this question using a combination of electron microscopy and hyperspectral confocal fluorescence microscopy in wild-type Synechocystis species PCC 6803 and a series of mutants in which phycobilisomes are progressively truncated. We show that as the phycobilisome antenna is diminished, large-scale changes in thylakoid morphology are observed, accompanied by increased physical segregation of the two photosystems. Finally, we quantified the emission intensities originating from the two photosystems in vivo on a per cell basis to show that the PSI:PSII ratio is progressively decreased in the mutants. This results from both an increase in the amount of photosystem II and a decrease in the photosystem I concentration. We propose that these changes are an adaptive strategy that allows cells to balance the light absorption capabilities of photosystems I and II under light-limiting conditions.","is_dataset_classified":null,"base_score":4.248495242049359,"endowment":4.248495242049359,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"22331410","pmcid":null,"openalex_id":"https://openalex.org/W2095882744","authors":[],"funders":[],"total_grants":0,"fwci":3.3133,"citation_percentile":0.93204038,"influential_citations":0,"citation_trend":[{"year":2012,"count":7},{"year":2013,"count":7},{"year":2014,"count":10},{"year":2015,"count":3},{"year":2016,"count":4},{"year":2017,"count":6},{"year":2018,"count":2},{"year":2019,"count":6},{"year":2020,"count":5},{"year":2021,"count":6},{"year":2022,"count":4},{"year":2024,"count":3},{"year":2025,"count":3},{"year":2026,"count":3}],"oa_status":"green","license":"https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model","oa_locations":[{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/3320172","host_type":"repository"},{"url":"https://www.ncbi.nlm.nih.gov/pmc/articles/3320172","host_type":"repository"},{"url":"http://academic.oup.com/plphys/article-pdf/158/4/1600/38111556/plphys_v158_4_1600.pdf","host_type":"publisher"},{"url":"https://doi.org/10.1104/pp.111.192849","host_type":"journal"},{"url":"https://pubmed.ncbi.nlm.nih.gov/22331410","host_type":"repository"}],"fields_of_study":["Photosynthetic Processes and Mechanisms","Algal biology and biofuel production","Metal-Catalyzed Oxygenation Mechanisms","Multivariate Analysis","Mutation","Phenylalanine Ammonia-Lyase","Photosynthesis","Photosynthetic Reaction Center Complex Proteins","Phycobilisomes","Phycocyanin","Spectrum Analysis","Synechocystis","Thylakoids"],"mesh_terms":["Mutation","Phenylalanine Ammonia-Lyase","Photosynthesis","Phycocyanin","Spectrum Analysis","Multivariate Analysis","Thylakoids","Photosynthetic Reaction Center Complex Proteins","Phycobilisomes","Synechocystis"],"keywords":["Phycobilisome","Thylakoid","Photosystem","Photosystem II","Photosystem I","Biology","Photosynthesis","Biophysics","Chloroplast","Synechocystis","Cyanobacteria","Botany","Biochemistry"],"sdg_mappings":[{"sdg_number":0,"sdg_label":"Clean water and sanitation"}],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-08-16T16:10:10.950640Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}