{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:39:37Z","timestamp":1786117177719,"version":"build-2736575974"},"reference-count":38,"publisher":"American Chemical Society (ACS)","issue":"31","license":[{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Large Stokes shift fluorescent protein (LSS FP) is a promising tool for biological research that is compatible with a broad range of advanced microscopy techniques. Here, we have investigated the ground-state heterogeneity and dynamics of two LSS FPs, LSSmOrange and mKeima, by two-dimensional fluorescence lifetime correlation spectroscopy. Both LSS FPs were found to have two states with distinct mean fluorescence lifetimes. From the pH-dependent change of relative populations, the states with short and long fluorescence lifetimes were assigned to the cis- and trans- forms of the chromophore, respectively. These states showed interconversion on two distinct time scales, submicroseconds to a few microseconds and submilliseconds to milliseconds. Excitation-power dependence and the symmetry of cross-correlations indicated that while the microsecond dynamics is thermally induced, the slow submillisecond dynamics is an irreversible photoinduced process. The knowledge obtained is expected to be helpful in the spectroscopic and imaging applications of LSS FPs.<\/jats:p>","DOI":"10.1021\/acs.jpclett.6c01414","type":"journal-article","created":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T19:55:28Z","timestamp":1784836528000},"page":"8798-8805","source":"Crossref","is-referenced-by-count":0,"title":["Intrinsic Fluorescence\nFluctuations of Large Stokes\nShift Fluorescent Proteins: LSSmOrange and mKeima Studied by Two-Dimensional\nFluorescence Lifetime Correlation Spectroscopy"],"prefix":"10.1021","volume":"17","author":[{"given":"Sandeep","family":"Yadav","sequence":"first","affiliation":[{"name":"RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5023-7581","authenticated-orcid":true,"given":"Bidyut","family":"Sarkar","sequence":"additional","affiliation":[{"name":"RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]},{"name":"Shiv Nadar Institution of Eminence , , ,","place":["Gautam Buddha Nagar, India, 201314"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuna","family":"Kinoshita","sequence":"additional","affiliation":[{"name":"Toho University , , 2-2-1 Miyama , ,","place":["Funabashi, Japan, 274-8510"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2316-5492","authenticated-orcid":true,"given":"Haruko","family":"Hosoi","sequence":"additional","affiliation":[{"name":"Toho University , , 2-2-1 Miyama , ,","place":["Funabashi, Japan, 274-8510"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6983-5255","authenticated-orcid":true,"given":"Hideaki","family":"Mizuno","sequence":"additional","affiliation":[{"name":"KU Leuven , , Celestijnenlaan 200G, bus 2403 , ,","place":["Leuven, Belgium, 3001"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5714-5997","authenticated-orcid":true,"given":"Kunihiko","family":"Ishii","sequence":"additional","affiliation":[{"name":"RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]},{"name":"RIKEN Center for Advanced Photonics (RAP), RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6340-8535","authenticated-orcid":true,"given":"Tahei","family":"Tahara","sequence":"additional","affiliation":[{"name":"RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]},{"name":"RIKEN Center for Advanced Photonics (RAP), RIKEN , , 2-1 Hirosawa , ,","place":["Wako, Japan, 351-0198"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,23]]},"reference":[{"issue":"24","key":"2026080609083307000_cit1","doi-asserted-by":"publisher","first-page":"4247","DOI":"10.1242\/jcs.005801","article-title":"Advances in fluorescent protein technology","volume":"120","author":"Shaner","year":"2007","journal-title":"J. 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U.S.A."},{"issue":"6","key":"2026080609083307000_cit34","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0099136","article-title":"Orange\nfluorescent proteins: structural studies of LSSmOrange, PSmOrange\nand PSmOrange2","volume":"9","author":"Pletnev","year":"2014","journal-title":"PLoS One"},{"issue":"1","key":"2026080609083307000_cit35","doi-asserted-by":"publisher","first-page":"35","DOI":"10.1016\/S0014-5793(03)00761-0","article-title":"Ground\nstate isomerization of a model\ngreen fluorescent protein chromophore","volume":"549","author":"He","year":"2003","journal-title":"FEBS\nLett."},{"issue":"2","key":"2026080609083307000_cit36","doi-asserted-by":"publisher","first-page":"167","DOI":"10.1002\/1439-7641(20020215)3:2&lt;167::AID-CPHC167&gt;3.0.CO;2-G","article-title":"Density functional\nstudies of the ground- and excited-state potential-energy curves of\nstilbene cis-trans isomerization","volume":"3","author":"Han","year":"2002","journal-title":"ChemPhysChem"},{"issue":"3","key":"2026080609083307000_cit37","doi-asserted-by":"publisher","first-page":"415","DOI":"10.1016\/S0006-3495(85)83933-3","article-title":"The effect\nof protonation and electrical\ninteractions on the stereochemistry of retinal Shiff bases","volume":"47","author":"Tavan","year":"1985","journal-title":"Biophys. 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Chem.\nSoc."}],"container-title":["The Journal of Physical\nChemistry Letters"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acs.jpclett.6c01414","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article-pdf\/17\/31\/8798\/66239902\/acs.jpclett.6c01414.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article-pdf\/17\/31\/8798\/66239902\/acs.jpclett.6c01414.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T13:16:30Z","timestamp":1786022190000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/jpclcd\/article\/17\/31\/8798\/5231368\/Intrinsic-Fluorescence-Fluctuations-of-Large"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,23]]},"references-count":38,"journal-issue":{"issue":"31","published-online":{"date-parts":[[2026,7,23]]},"published-print":{"date-parts":[[2026,8,6]]}},"URL":"https:\/\/doi.org\/10.1021\/acs.jpclett.6c01414","relation":{},"ISSN":["1948-7185"],"issn-type":[{"value":"1948-7185","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,23]]}}}