{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T20:36:27Z","timestamp":1780691787325,"version":"3.54.1"},"reference-count":30,"publisher":"Wiley","issue":"6","license":[{"start":{"date-parts":[[2011,4,12]],"date-time":"2011-04-12T00:00:00Z","timestamp":1302566400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"funder":[{"DOI":"10.13039\/501100001711","name":"Swiss National Science Foundation","doi-asserted-by":"crossref","award":["3100A0-109290"],"award-info":[{"award-number":["3100A0-109290"]}],"id":[{"id":"10.13039\/501100001711","id-type":"DOI","asserted-by":"crossref"}]},{"name":"The Zwahlen Grant from the Faculty of Biology and Medicine, University of Lausanne"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Proteins"],"published-print":{"date-parts":[[2011,6]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>During mild heat\u2013stress, a native thermolabile polypeptide may partially unfold and transiently expose water\u2010avoiding hydrophobic segments that readily tend to associate into a stable misfolded species, rich in intra\u2010molecular non\u2010native beta\u2010sheet structures. When the concentration of the heat\u2010unfolded intermediates is elevated, the exposed hydrophobic segments tend to associate with other molecules into large stable insoluble complexes, also called \u201caggregates.\u201d In mammalian cells, stress\u2010 and mutation\u2010induced protein misfolding and aggregation may cause degenerative diseases and aging. Young cells, however, effectively counteract toxic protein misfolding with a potent network of molecular chaperones that bind hydrophobic surfaces and actively unfold otherwise stable misfolded and aggregated polypeptides. Here, we followed the behavior of a purified, initially mostly native thermolabile luciferase mutant, in the presence or absence of the <jats:italic>Escherichia coli<\/jats:italic> DnaK\u2010DnaJ\u2010GrpE chaperones and\/or of ATP, at 22\u00b0C or under mild heat\u2013stress. We concomitantly measured luciferase enzymatic activity, Thioflavin\u2010T fluorescence, and light\u2010scattering to assess the effects of temperature and chaperones on the formation, respectively, of native, unfolded, misfolded, and\/or of aggregated species. During mild heat\u2010denaturation, DnaK\u2010DnaJ\u2010GrpE+ATP best maintained, although transiently, high luciferase activity and best prevented heat\u2010induced misfolding and aggregation. In contrast, the ATP\u2010less DnaK and DnaJ did not maintain optimal luciferase activity and were less effective at preventing luciferase misfolding and aggregation. We present a model accounting for the experimental data, where native, unfolded, misfolded, and aggregated species spontaneously inter\u2010convert, and in which DnaK\u2010DnaJ\u2010GrpE+ATP specifically convert stable misfolded species into unstable unfolded intermediates. Proteins 2011; \u00a9 2011 Wiley\u2010Liss, Inc.<\/jats:p>","DOI":"10.1002\/prot.23024","type":"journal-article","created":{"date-parts":[[2011,3,7]],"date-time":"2011-03-07T16:36:19Z","timestamp":1299515779000},"page":"1991-1998","source":"Crossref","is-referenced-by-count":37,"title":["Probing the different chaperone activities of the bacterial HSP70\u2010HSP40 system using a thermolabile luciferase substrate"],"prefix":"10.1002","volume":"79","author":[{"given":"Sandeep K.","family":"Sharma","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"De Los Rios","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre","family":"Goloubinoff","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2011,4,12]]},"reference":[{"key":"e_1_2_6_2_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.181.4096.223"},{"key":"e_1_2_6_3_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.83.21.8069"},{"key":"e_1_2_6_4_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.bbapap.2003.12.008"},{"key":"e_1_2_6_5_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M209163200"},{"key":"e_1_2_6_6_2","doi-asserted-by":"publisher","DOI":"10.1017\/S0033583506004422"},{"key":"e_1_2_6_7_2","doi-asserted-by":"publisher","DOI":"10.1038\/nrm2873"},{"key":"e_1_2_6_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/0022-2836(91)90499-V"},{"key":"e_1_2_6_9_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M405627200"},{"key":"e_1_2_6_10_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.96.24.13732"},{"key":"e_1_2_6_11_2","doi-asserted-by":"publisher","DOI":"10.1038\/nchembio.455"},{"key":"e_1_2_6_12_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0968-0004(01)01938-7"},{"key":"e_1_2_6_13_2","doi-asserted-by":"publisher","DOI":"10.1385\/JMN:30:3:249"},{"key":"e_1_2_6_14_2","doi-asserted-by":"publisher","DOI":"10.1038\/nature02261"},{"key":"e_1_2_6_15_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M110.127753"},{"key":"e_1_2_6_16_2","doi-asserted-by":"publisher","DOI":"10.1021\/bi036049"},{"key":"e_1_2_6_17_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1432-1033.1996.0318n.x"},{"key":"e_1_2_6_18_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.270.5.2183"},{"key":"e_1_2_6_19_2","doi-asserted-by":"publisher","DOI":"10.1134\/S0026893307010128"},{"key":"e_1_2_6_20_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M103081200"},{"key":"e_1_2_6_21_2","doi-asserted-by":"publisher","DOI":"10.3410\/B1-41"},{"key":"e_1_2_6_22_2","doi-asserted-by":"publisher","DOI":"10.1021\/bi00220a020"},{"key":"e_1_2_6_23_2","doi-asserted-by":"publisher","DOI":"10.1038\/418291a"},{"key":"e_1_2_6_24_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-2836(02)00735-0"},{"key":"e_1_2_6_25_2","doi-asserted-by":"publisher","DOI":"10.2174\/138920309789351930"},{"key":"e_1_2_6_26_2","doi-asserted-by":"publisher","DOI":"10.1074\/jbc.M403672200"},{"key":"e_1_2_6_27_2","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-313X.2002.01364.x"},{"key":"e_1_2_6_28_2","article-title":"Heat perception and signalling in plants: a tortuous path to thermotolerance","author":"Saidi Y","journal-title":"New Phytol"},{"key":"e_1_2_6_29_2","doi-asserted-by":"publisher","DOI":"10.1021\/ja806146g"},{"key":"e_1_2_6_30_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0092-8674(00)81223-4"},{"key":"e_1_2_6_31_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0903503106"}],"container-title":["Proteins: Structure, Function, and Bioinformatics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fprot.23024","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fprot.23024","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/prot.23024","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,15]],"date-time":"2023-10-15T13:41:41Z","timestamp":1697377301000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/prot.23024"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,4,12]]},"references-count":30,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2011,6]]}},"alternative-id":["10.1002\/prot.23024"],"URL":"https:\/\/doi.org\/10.1002\/prot.23024","archive":["Portico"],"relation":{},"ISSN":["0887-3585","1097-0134"],"issn-type":[{"value":"0887-3585","type":"print"},{"value":"1097-0134","type":"electronic"}],"subject":[],"published":{"date-parts":[[2011,4,12]]}}}