title: NMR studies on binding sites and aggregation-disassociation of fluorinated surfactant sodium perfluorooctanoate on protein ubiquitin.
abstract: The fluorinated surfactant sodium perfluorooctanoate (SPFO) could bind onto ubiquitin (UBQ) and induce the unfolding of UBQ. By using (15)N-edited heteronuclear single-quantum coherence (HSQC) NMR and (19)F NMR to monitor (15)N-labeled UBQ and SPFO, respectively, the binding sites and the aggregation process of SPFO on UBQ at various SPFO concentrations were observed. A detailed process from specific binding to cooperative binding of SPFO on UBQ, and a detailed structure change of UBQ upon the increase of SPFO concentration were obtained. The refolding of UBQ in UBQ-SPFO complex was carried out by adding cationic surfactant. It was shown that added cationic surfactants formed mixed micelles with SPFO and resulted in the dissociation of the UBQ-SPFO complex, and consequently, most ubiquitin could be refolded to its native state.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Run-Chao
authors.initials: RC
authors.lastname: Lu
authors.forename: Xian-Rong
authors.initials: XR
authors.lastname: Guo
authors.forename: Changwen
authors.initials: C
authors.lastname: Jin
authors.forename: Jin-Xin
authors.initials: JX
authors.lastname: Xiao
mesh_terms: D001665:Binding Sites; D002210:Caprylates / Q000494:pharmacology*; D011232:Chemical Precipitation; D005466:Fluorocarbons / Q000494:pharmacology*; D008954:Models, Biological; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D017510:Protein Folding / Q000187:drug effects; D013501:Surface-Active Agents / Q000494:pharmacology; D025801:Ubiquitin / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism*
chemical_list: D002210:Caprylates; D005466:Fluorocarbons; D013501:Surface-Active Agents; D025801:Ubiquitin; C023036:perfluorooctanoic acid