{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T20:16:38Z","timestamp":1788466598535,"version":"build-2803163510"},"reference-count":46,"publisher":"American Chemical Society (ACS)","issue":"35","license":[{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T00:00:00Z","timestamp":1787529600000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP21H01898"],"award-info":[{"award-number":["JP21H01898"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001700","name":"Ministry of Education, Culture, Sports, Science and Technology","doi-asserted-by":"publisher","award":["JPMXS0120330644"],"award-info":[{"award-number":["JPMXS0120330644"]}],"id":[{"id":"10.13039\/501100001700","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100018790","name":"National Institutes for Quantum Science and Technology","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/501100018790","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Phycobiliproteins serve as highly efficient light-harvesting antennae in cyanobacteria, yet the molecular factors governing their ultrafast energy relaxation and coherence dynamics remain incompletely understood. In this study, we investigate the role of pigment arrangement and pigment\u2013protein interactions by combining recombinant protein engineering with two-dimensional electronic spectroscopy (2D-ES). In addition to wild-type allophycocyanin (APC) and C-phycocyanin (CPC), we artificially synthesized a \u03b2153 phycocyanobilin (PCB)-deficient CPC mutant, enabling direct experimental isolation of the contribution of this isolated pigment. The absorption and fluorescence spectra show that removal of the \u03b2153 pigment primarily eliminates its spectral contribution without significantly altering the excitonic coupling between the \u03b184 and \u03b284 pigments. Time-resolved 2D-ES reveals the close similarity between the dynamics of wild-type and \u03b2153-deficient CPCs, which demonstrates that the \u03b2153 pigment plays a minor role in ultrafast relaxation dynamics. Instead, the differences between APC and CPC arise primarily from pigment\u2013protein interactions that modulate pigment structure and vibronic states. These results highlight the critical importance of local protein environments in controlling energy relaxation and coherence in photosynthetic light-harvesting proteins<\/jats:p>","DOI":"10.1021\/acs.jpcb.6c03553","type":"journal-article","created":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T12:42:39Z","timestamp":1788093759000},"page":"8815-8829","source":"Crossref","is-referenced-by-count":0,"title":["Roles of Individual\nPigments in Ultrafast Excitation\nDynamics of Light-Harvesting Phycobiliproteins Revealed by Recombinant\nTechniques and Two-Dimensional Electronic Spectroscopy"],"prefix":"10.1021","volume":"130","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1158-0867","authenticated-orcid":true,"given":"Masaaki","family":"Tsubouchi","sequence":"first","affiliation":[{"name":"National Institutes for Quantum Science and Technology (QST) , , 8-1-7 Umemidai , , ,","place":["Kizugawa, Kyoto, Japan, 619-0215"]},{"name":"National Institutes for Quantum Science and Technology (QST) , , 4-9-1 Anagawa , Inage, ,","place":["Chiba, Japan, 263-8555"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1504-2249","authenticated-orcid":true,"given":"Takatoshi","family":"Fujita","sequence":"additional","affiliation":[{"name":"National Institutes for Quantum Science and Technology (QST) , , 4-9-1 Anagawa , Inage, ,","place":["Chiba, Japan, 263-8555"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2353-880X","authenticated-orcid":true,"given":"Motoyasu","family":"Adachi","sequence":"additional","affiliation":[{"name":"National Institutes for Quantum Science and Technology (QST) , , 4-9-1 Anagawa , Inage, ,","place":["Chiba, Japan, 263-8555"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryuji","family":"Itakura","sequence":"additional","affiliation":[{"name":"National Institutes for Quantum Science and Technology (QST) , , 8-1-7 Umemidai , , ,","place":["Kizugawa, Kyoto, Japan, 619-0215"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,8,24]]},"reference":[{"key":"2026090315294692500_cit1","doi-asserted-by":"publisher","first-page":"781","DOI":"10.2307\/1297221","article-title":"Phycobilisomes:\nlight-harvesting pigment complexes","volume":"25","author":"Gantt","year":"1975","journal-title":"Bioscience"},{"key":"2026090315294692500_cit2","volume-title":"Molecular\nmechanisms of photosynthesis","author":"Blankenship","year":"2021"},{"key":"2026090315294692500_cit3","doi-asserted-by":"publisher","first-page":"5497","DOI":"10.1038\/s41467-021-25813-y","article-title":"Structural insight into the mechanism\nof energy transfer in cyanobacterial phycobilisomes","volume":"12","author":"Zheng","year":"2021","journal-title":"Nat. Commun."},{"key":"2026090315294692500_cit4","doi-asserted-by":"publisher","first-page":"146","DOI":"10.1038\/s41586-020-2020-7","article-title":"Structural\nbasis of energy transfer in porphyridium purpureum phycobilisome","volume":"579","author":"Ma","year":"2020","journal-title":"Nature"},{"key":"2026090315294692500_cit5","doi-asserted-by":"publisher","first-page":"835","DOI":"10.1038\/s41586-022-05156-4","article-title":"Structures of a phycobilisome in\nlight-harvesting and\nphotoprotected states","volume":"609","author":"Domi\u0301nguez-Marti\u0301n","year":"2022","journal-title":"Nature"},{"key":"2026090315294692500_cit6","doi-asserted-by":"publisher","first-page":"3389","DOI":"10.1038\/s41467-022-30962-9","article-title":"Core and rod structures of a thermophilic\ncyanobacterial light-harvesting phycobilisome","volume":"13","author":"Kawakami","year":"2022","journal-title":"Nat. Commun."},{"key":"2026090315294692500_cit7","doi-asserted-by":"publisher","first-page":"1286","DOI":"10.1038\/s41557-022-01026-8","article-title":"Excitation energy transfer and vibronic\ncoherence in\nintact phycobilisomes","volume":"14","author":"Sil","year":"2022","journal-title":"Nat. Chem."},{"key":"2026090315294692500_cit8","doi-asserted-by":"publisher","first-page":"11659","DOI":"10.1021\/jacs.3c01799","article-title":"Phycobilisome\u2019s exciton transfer\nefficiency\nrelies on an energetic funnel driven by chromophore\u2013linker\nprotein interactions","volume":"145","author":"Sohoni","year":"2023","journal-title":"J. Am. Chem. Soc."},{"key":"2026090315294692500_cit9","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1021\/acs.jpcb.1c06509","article-title":"Annihilation\nof\nexcess excitations along phycocyanin rods precedes downhill flow to\nallophycocyanin cores in the phycobilisome of synechococcus elongatus\nPCC 7942","volume":"126","author":"Navotnaya","year":"2022","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit10","doi-asserted-by":"publisher","first-page":"181","DOI":"10.1007\/s11120-021-00844-0","article-title":"Ultrafast energy transfer\ndynamics of phycobilisome\nfrom thermosynechococcus vulcanus, as revealed by ps fluorescence\nand fs pump-probe spectroscopies","volume":"148","author":"Hirota","year":"2021","journal-title":"Photosynth.\nRes."},{"key":"2026090315294692500_cit11","doi-asserted-by":"publisher","first-page":"424","DOI":"10.1006\/jmbi.1995.0307","article-title":"Isolation,\ncrystallization, crystal structure analysis and refinement of allophycocyanin\nfrom the cyanobacterium Spirulina platensis at 2.3 \u00c5 resolution","volume":"249","author":"Brejc","year":"1995","journal-title":"J. Mol. Biol."},{"key":"2026090315294692500_cit12","doi-asserted-by":"publisher","first-page":"15771","DOI":"10.1021\/jp908093x","article-title":"Nature of excited states and relaxation mechanisms\nin C-phycocyanin","volume":"113","author":"Womick","year":"2009","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit13","doi-asserted-by":"publisher","first-page":"15699","DOI":"10.1021\/j100043a001","article-title":"Evidence\nfor coherent energy transfer\nin allophycocyanin trimers","volume":"99","author":"Edington","year":"1995","journal-title":"J. Phys. Chem."},{"key":"2026090315294692500_cit14","doi-asserted-by":"publisher","first-page":"14206","DOI":"10.1021\/jp960454b","article-title":"Interexciton-state\nrelaxation and\nexciton localization in allophycocyanin trimers","volume":"100","author":"Edington","year":"1996","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit15","doi-asserted-by":"publisher","first-page":"4473","DOI":"10.1021\/jp970424o","article-title":"Femtosecond transient hole-burning\ndetection of interexciton-state radiationless decay in allophycocyanin\ntrimers","volume":"101","author":"Edington","year":"1997","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit16","doi-asserted-by":"publisher","first-page":"3044","DOI":"10.1021\/jp972782x","article-title":"Stimulated photon-echo\nand transient-grating studies of protein-matrix solvation dynamics\nand interexciton-state radiationless decay in \u03b1 phycocyanin\nand allophycocyanin","volume":"102","author":"Homoelle","year":"1998","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit17","doi-asserted-by":"publisher","first-page":"8878","DOI":"10.1021\/jp011266a","article-title":"Investigations\nof ultrafast exciton\ndynamics in allophycocyanin trimer","volume":"105","author":"Zhang","year":"2001","journal-title":"J. Phys.\nChem. A"},{"key":"2026090315294692500_cit18","doi-asserted-by":"publisher","first-page":"15747","DOI":"10.1021\/jp907644h","article-title":"Exciton\ncoherence and energy transport in the light-harvesting\ndimers of allophycocyanin","volume":"113","author":"Womick","year":"2009","journal-title":"J. Phys. Chem. B"},{"key":"2026090315294692500_cit19","doi-asserted-by":"publisher","first-page":"024507","DOI":"10.1063\/1.3457378","article-title":"Toward\nthe origin of exciton electronic\nstructure in phycobiliproteins","volume":"133","author":"Womick","year":"2010","journal-title":"J. Chem. Phys."},{"key":"2026090315294692500_cit20","doi-asserted-by":"publisher","first-page":"1347","DOI":"10.1021\/jp106713q","article-title":"Vibronic enhancement of exciton sizes and energy transport\nin photosynthetic complexes","volume":"115","author":"Womick","year":"2011","journal-title":"J. Phys. 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Lett."},{"key":"2026090315294692500_cit27","doi-asserted-by":"publisher","first-page":"145102","DOI":"10.1063\/5.0260776","article-title":"Dependence\nof energy relaxation and vibrational coherence on the location of\nlight-harvesting chromoproteins in photosynthetic antenna protein\ncomplexes","volume":"162","author":"Tsubouchi","year":"2025","journal-title":"J. Chem. Phys."},{"key":"2026090315294692500_cit28","doi-asserted-by":"publisher","first-page":"3343","DOI":"10.1021\/jacs.5c18051","article-title":"Biosynthesis\nof Minimal C-Phycocyanin Chromophore Assemblies\nin E. coli Provides a Platform to Dissect\nProtein-Mediated Tuning of Exciton Transfer","volume":"148","author":"Zhuang","year":"2026","journal-title":"J. Am. Chem. 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Signatures of coherent electronic motion\nand exciton population transfer in dimer two-dimensional spectra","volume":"124","author":"Pisliakov","year":"2006","journal-title":"J. Chem. Phys."},{"key":"2026090315294692500_cit35","doi-asserted-by":"publisher","first-page":"1904","DOI":"10.1021\/jz200811p","article-title":"Comparison of electronic\nand vibrational coherence measured by two-dimensional electronic spectroscopy","volume":"2","author":"Turner","year":"2011","journal-title":"J. Phys. Chem. Lett."},{"key":"2026090315294692500_cit36","doi-asserted-by":"publisher","first-page":"333","DOI":"10.1146\/annurev-conmatphys-020911-125126","article-title":"Quantum coherence in photosynthetic light harvesting","volume":"3","author":"Ishizaki","year":"2012","journal-title":"Annu. Rev. Condens. 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Instrum."},{"key":"2026090315294692500_cit44","doi-asserted-by":"crossref","first-page":"174201","DOI":"10.1063\/1.4966196","article-title":"Estimation\nof damped oscillation associated spectra from ultrafast transient\nabsorption spectra","volume":"145","author":"van Stokkum","year":"2016","journal-title":"J. Chem. Phys."},{"key":"2026090315294692500_cit45","doi-asserted-by":"crossref","first-page":"114113","DOI":"10.1063\/5.0060672","article-title":"Vibronic\ndynamics resolved by global and target analysis of ultrafast transient\nabsorption spectra","volume":"155","author":"van Stokkum","year":"2021","journal-title":"J. Chem. Phys."},{"key":"2026090315294692500_cit46","doi-asserted-by":"publisher","first-page":"2774","DOI":"10.1021\/jz100972z","article-title":"Two-Dimensional Electronic Spectroscopy of the D1-D2-cyt\nb559 Photosystem II Reaction Center Complex","volume":"1","author":"Myers","year":"2010","journal-title":"J. Phys. Chem. Lett."}],"container-title":["The Journal of Physical\nChemistry B"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acs.jpcb.6c03553","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/jpcbfk\/article-pdf\/130\/35\/8815\/67322341\/acs.jpcb.6c03553.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/jpcbfk\/article-pdf\/130\/35\/8815\/67322341\/acs.jpcb.6c03553.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T19:29:56Z","timestamp":1788463796000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/jpcbfk\/article\/130\/35\/8815\/5321180\/Roles-of-Individual-Pigments-in-Ultrafast"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,24]]},"references-count":46,"journal-issue":{"issue":"35","published-online":{"date-parts":[[2026,8,24]]},"published-print":{"date-parts":[[2026,9,3]]}},"URL":"https:\/\/doi.org\/10.1021\/acs.jpcb.6c03553","relation":{},"ISSN":["1520-6106","1520-5207"],"issn-type":[{"value":"1520-6106","type":"print"},{"value":"1520-5207","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,24]]}}}