Publication date: Available online 23 July 2013 Source:Journal of Magnetic Resonance
Author(s): Juan Lopez , Puneet Ahuja , Melanie Gérard , Jean Michel Wieruszeski , Guy Lippens
We describe a new efficient strategy for the sequential assignment of amide resonances of a conventional 15N-1H HSQC spectrum of intrinsically unfolded proteins, based on composite NOESY-TOCSY and TOCSY-NOESY mixing times. These composite mixing times lead to a H?-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 ?-synuclein.
An assignment of intrinsically disordered regions of proteins based on NMR structures
An assignment of intrinsically disordered regions of proteins based on NMR structures
January 2013
Publication year: 2013
Source:Journal of Structural Biology, Volume 181, Issue 1</br>
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Intrinsically disordered proteins (IDPs) do not adopt stable three-dimensional structures in physiological conditions, yet these proteins play crucial roles in biological phenomena. In most cases, intrinsic disorder manifests itself in segments or domains of an IDP, called intrinsically disordered regions (IDRs), but fully disordered IDPs also exist. Although IDRs can be detected as...
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02-03-2013 10:13 AM
4D Non-uniformly sampled HCBCACON and 1J(NCα)-selective HCBCANCO experiments for the sequential assignment and chemical shift analysis of intrinsically disordered proteins
4D Non-uniformly sampled HCBCACON and 1J(NCα)-selective HCBCANCO experiments for the sequential assignment and chemical shift analysis of intrinsically disordered proteins
Abstract A pair of 4D NMR experiments for the backbone assignment of disordered proteins is presented. The experiments exploit 13C direct detection and non-uniform sampling of the indirectly detected dimensions, and provide correlations of the aliphatic proton (Hα, and Hβ) and carbon (Cα, Cβ) resonance frequencies to the protein backbone. Thus, all the chemical shifts regularly used to map the transient...
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05-17-2012 08:40 AM
An optimized isotopic labelling strategy of isoleucine-?(2) methyl groups for solution NMR studies of high molecular weight proteins.
An optimized isotopic labelling strategy of isoleucine-?(2) methyl groups for solution NMR studies of high molecular weight proteins.
An optimized isotopic labelling strategy of isoleucine-?(2) methyl groups for solution NMR studies of high molecular weight proteins.
Chem Commun (Camb). 2011 Jul 26;
Authors: Ayala I, Hamelin O, Amero C, Pessey O, Plevin MJ, Gans P, Boisbouvier J
An efficient synthetic route is proposed to produce 2-hydroxy-2-ethyl-3-oxobutanoate for the specific labelling of Ile methyl-?(2) groups in proteins. The (2)H,...
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07-28-2011 10:51 AM
5D 13C-detected experiments for backbone assignment of unstructured proteins with a very low signal dispersion
5D 13C-detected experiments for backbone assignment of unstructured proteins with a very low signal dispersion
Abstract Two novel 5D NMR experiments (CACONCACO, NCOCANCO) for backbone assignment of disordered proteins are presented. The pulse sequences exploit relaxation properties of the unstructured proteins and combine the advantages of 13C-direct detection, non-uniform sampling, and longitudinal relaxation optimization to maximize the achievable resolution and minimize the experimental time. The pulse sequences were successfully tested on the sample of partially disordered delta...
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03-22-2011 07:32 PM
Suppression of isotope scrambling in cell-free protein synthesis by broadband inhibition of PLP enymes for selective 15N-labelling and production of perdeuterated proteins in H2O
Suppression of isotope scrambling in cell-free protein synthesis by broadband inhibition of PLP enymes for selective 15N-labelling and production of perdeuterated proteins in H2O
Abstract Selectively isotope labelled protein samples can be prepared in vivo or in vitro from selectively labelled amino acids but, in many cases, metabolic conversions between different amino acids result in isotope scrambling. The best results are obtained by cell-free protein synthesis, where metabolic enzymes are generally less active, but isotope scrambling can never be suppressed completely. We show that...
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02-16-2011 09:34 PM
Extension of the HA-detection based approach: (HCA)CON(CA)H and (HCA)NCO(CA)H experiments for the main-chain assignment of intrinsically disordered proteins
Extension of the HA-detection based approach: (HCA)CON(CA)H and (HCA)NCO(CA)H experiments for the main-chain assignment of intrinsically disordered proteins
Abstract Extensive resonance overlap exacerbates assignment of intrinsically disordered proteins (IDPs). This issue can be circumvented by utilizing 15N, 13C� and 1HN spins, where the chemical shift dispersion is mainly dictated by the characteristics of consecutive amino acid residues. Especially 15N and 13C� spins offer superior chemical shift dispersion in comparison to 13Cα and 13Cβ spins. However, HN-detected experiments...
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01-29-2011 05:31 AM
Cell-free expression and stable isotope labelling strategies for membrane proteins
Cell-free expression and stable isotope labelling strategies for membrane proteins
Abstract Membrane proteins are highly underrepresented in the structural data-base and remain one of the most challenging targets for functional and structural elucidation. Their roles in transport and cellular communication, furthermore, often make over-expression toxic to their host, and their hydrophobicity and structural complexity make isolation and reconstitution a complicated task, especially in cases where proteins are targeted to inclusion bodies. The development of cell-free expression systems...
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01-09-2011 12:46 PM
[NMR paper] NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
Related Articles NMR relaxation studies on the hydrate layer of intrinsically unstructured proteins.
Biophys J. 2005 Mar;88(3):2030-7
Authors: Bokor M, Csizmók V, Kovács D, Bánki P, Friedrich P, Tompa P, Tompa K
Intrinsically unstructured/disordered proteins (IUPs) exist in a disordered and largely solvent-exposed, still functional, structural state under physiological conditions. As their function is often directly linked with structural disorder,...