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 segments along the polypeptide chain observed in HNN are retained and these provide start and check points for the sequential walk. Because of co-incrementing of CA andN, peaks along one of the dimensions appear at sums and differences of the CAandN chemical shifts. This changes the backbone assignment protocol slightly and we present this in explicit detail. The performance of the experiment has been demonstrated using Ubiquitin and Plasmodium falciparum P2 proteins. The experiment is particularly valuable when two neighboring amino acid residues have nearly identical backboneN chemical shifts.</br>
Graphical abstract


http://www.sciencedirect.com/cache/M...000535-fx1.sml</br>Highlights

? 3D HNCANincorporates CA and N co-evolution in HNN. ? Provides HN, N and CA backbone assignments. ? Reduced dimensionality enhances spectral dispersion.</br></br>

Source: Journal of Magnetic Resonance