[NMR paper] Reduced Dimensionality tailored HN(C)N Experiments for Facile Backbone Resonance Assignment of Proteins through Unambiguous Identification of Sequential HSQC Peaks
Reduced Dimensionality tailored HN(C)N Experiments for Facile Backbone Resonance Assignment of Proteins through Unambiguous Identification of Sequential HSQC Peaks
Publication date: Available online 8 October 2013 Source:Journal of Magnetic Resonance
Author(s): Dinesh Kumar
Two novel reduced dimensionality (RD) tailored HN(C)N [Panchal et. al., J. Biomol. NMR. (2002), 20 (2), 135-147] experiments are proposed to facilitate the backbone resonance assignment of proteins both in terms of its accuracy and speed. These experiments -referred here as (4,3)D-hNCOcaNH and (4,3)D-hNcoCANH- exploit the linear combination of backbone 15N and 13C?/13C? chemical shifts simultaneously to achieve higher peak dispersion and randomness along their respective F 1 dimensions. Simply, this has been achieved by modulating the backbone 15N(i) chemical shifts with that of 13C?(i-1)/13C? (i-1) spins following the established reduced dimensionality NMR approach [Szyperski et. al. (2002), Proc. Natl. Acad. Sci. U.S.A. 99(12), 8009-8014]. Though the modification is simple it has resulted an ingenious improvement of HN(C)N both in terms of peak dispersion and easiness of establishing the sequential connectivities. The increased dispersion along F 1 dimension solves two purposes here: (i) resolves the ambiguities arising because of degenerate 15N chemical shifts and (ii) reduces the signal overlap in F 2(15N)- F 3(1H) planes (an important requisite in HN(C)N based assignment protocol for facile and unambiguous identification of sequentially connected HSQC peaks). The performance of both these experiments and the assignment protocol has been demonstrated using bovine apo Calbindin-d9k (75 aa) and urea denatured UNC60B (a 152 amino acid ADF/cofilin family protein of Caenorhabditis elegans), as representatives of folded and unfolded protein systems, respectively. Graphical abstract
Reduced dimensionality 3D HNCAN for unambiguous HN, CA and N assignment in proteins
Reduced dimensionality 3D HNCAN for unambiguous HN, CA and N assignment in proteins
Publication year: 2012
Source:Journal of Magnetic Resonance</br>
Manoj Kumar Rout, Pushpa Mishra, Hanudatta S. Atreya, Ramakrishna V. Hosur</br>
We present here an improvisation of HNN (Panchal, Bhavesh et al., 2001) called RD 3D HNCAN for backbone (HN, CA and 15N) assignment in both folded and unfolded proteins. This is a reduced dimensionality experiment which employs CA chemical shifts to improve dispersion. Distinct positive and negative peak patterns of various triplet segments...
nmrlearner
Journal club
0
03-09-2012 09:16 AM
Reduced dimensionality 3D HNCANfor unambiguous HN, CA and N assignment in proteins
Reduced dimensionality 3D HNCANfor unambiguous HN, CA and N assignment in proteins
Publication year: 2012
Source: Journal of Magnetic Resonance, Available online 8 February 2012</br>
Manoj Kumar*Rout, Pushpa*Mishra, Hanudatta S.*Atreya, Ramakrishna V.*Hosur</br>
We present here an improvisation of HNN (Panchal, Bhavesh et al. 2001)called RD 3D HNCANfor backbone (HN, CA andN) assignment inboth folded and unfolded proteins. This is a reduced dimensionality experiment which employsCAchemical shifts to improve dispersion. Distinct positive and negative peak patternsof various triplet...
nmrlearner
Journal club
0
02-10-2012 09:13 AM
Efficient sequential assignments in proteins with reduced dimensionality 3D HN(CA)NH
Efficient sequential assignments in proteins with reduced dimensionality 3D HN(CA)NH
Abstract We present reduced dimensionality (RD) 3D HN(CA)NH for efficient sequential assignment in proteins. The experiment correlates the 15N and 1H chemical shift of a residue (â??iâ??) with those of its immediate N-terminal (i â?? 1) and C-terminal (i + 1) neighbors and provides four-dimensional chemical shift correlations rapidly with high resolution. An assignment strategy is presented which combines the correlations observed in this experiment with amino acid type information obtained from 3D ...
nmrlearner
Journal club
0
01-09-2012 08:08 AM
Aliasing in reduced dimensionality NMR spectra: (3,2)D HNHA and (4,2)D HN(COCA)NH experiments as examples
Aliasing in reduced dimensionality NMR spectra: (3,2)D HNHA and (4,2)D HN(COCA)NH experiments as examples
Abstract Reduced dimensionality NMR spectra usually require very large spectral widths in the shared dimension. In this paper we show that aliasing can be introduced in reduced dimensionality NMR spectra either to decrease the acquisition time or increase the resolution of the experiments without losing information. The gains of introducing aliasing are illustrated with two examples, the (3,2)D HNHA and the (4,2)D HN(COCA)NH experiments. In both cases a reduction of the spectral...
nmrlearner
Journal club
0
01-09-2011 12:46 PM
Sparsely-sampled High-resolution 4-D Experiments for Efficient Backbone Resonance Assignment of Disordered Proteins
Sparsely-sampled High-resolution 4-D Experiments for Efficient Backbone Resonance Assignment of Disordered Proteins
Publication year: 2011
Source: Journal of Magnetic Resonance, In Press, Accepted Manuscript, Available online 4 January 2011</br>
Jie, Wen , Jihui, Wu , Pei, Zhou</br>
Intrinsically disordered proteins (IDPs) play important roles in many critical cellular processes. Due to their limited chemical shift dispersion, IDPs often require four pairs of resonance connectivities (H?, C?, C? and CO) for establishing sequential backbone assignment. Because most conventional 4-D...
nmrlearner
Journal club
0
01-05-2011 11:03 AM
Pseudo-4D triple resonance experiments to resolve HN overlap in the backbone assignment of unfolded proteins
Pseudo-4D triple resonance experiments to resolve HN overlap in the backbone assignment of unfolded proteins
Abstract The solution NMR resonance assignment of the protein backbone is most commonly carried out using triple resonance experiments that involve 15N and 1HN resonances. The assignment becomes problematic when there is resonance overlap of 15Nâ??1HN cross peaks. For such residues, one cannot unambiguously link the â??leftâ?? side of the NH root to the â??rightâ?? side, and the residues associated with such overlapping HN resonances remain often unassigned. Here we present a...
nmrlearner
Journal club
0
12-31-2010 08:38 PM
[NMR paper] New (15)N NMR exchange experiments for the unambiguous assignment of (1)H(N)/(15)N re
New (15)N NMR exchange experiments for the unambiguous assignment of (1)H(N)/(15)N resonances of proteins in complexes in slow chemical exchange with free form.
Related Articles New (15)N NMR exchange experiments for the unambiguous assignment of (1)H(N)/(15)N resonances of proteins in complexes in slow chemical exchange with free form.
J Magn Reson. 2000 Feb;142(2):276-9
Authors: Vialle-Printems C, van Heijenoort C, Guittet E
The potentialities of a 2D proton-detected heteronuclear exchange experiment to assign the nitrogen and amide proton...