title: A new strategy for sequential assignment of intrinsically unstructured proteins based on 15N single isotope labelling.
abstract: We describe a new efficient strategy for the sequential assignment of amide resonances of a conventional (15)N-(1)H HSQC spectrum of intrinsically unfolded proteins, based on composite NOESY-TOCSY and TOCSY-NOESY mixing times. These composite mixing times lead to a Hα-proton mediated unidirectional transfer of amide to amide proton. We have implemented the composite mixing times in an HSQC-NOESY-HSQC manner to obtain directional connectivity between amides of neighbouring residues. We experimentally determine the optimal mixing times for both transfer schemes, and demonstrate its use in the assignment for both a fragment of the neuronal tau protein and for α-synuclein.
authors.affiliation: CNRS UMR 8576, Unité de Glycobiologie Structurale et Fonctionnelle, Université des Sciences et Technologies de Lille 1, 59655 Villeneuve d'Ascq Cedex, France.
authors.forename: Juan
authors.initials: J
authors.lastname: Lopez
authors.forename: Puneet
authors.initials: P
authors.lastname: Ahuja
authors.forename: Melanie
authors.initials: M
authors.lastname: Gerard
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Wieruszeski
authors.forename: Guy
authors.initials: G
authors.lastname: Lippens
mesh_terms: D000577:Amides / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D004574:Electromagnetic Fields; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism; D007553:Isotope Labeling / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D009587:Nitrogen Isotopes; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D011522:Protons; D051844:alpha-Synuclein / Q000737:chemistry
chemical_list: D000577:Amides; D009587:Nitrogen Isotopes; D011506:Proteins; D011522:Protons; D051844:alpha-Synuclein; D002244:Carbon
keywords: Assignment; Intrinsically unstructured protein; NOESY; TOCSY