caa a22 4500 445325011 CHVBK 20180317142717.0 cr unu---uuuuu 170323e20110201xx s 000 0 eng 10.1007/s10858-010-9465-1 doi (NATIONALLICENCE)springer-10.1007/s10858-010-9465-1 Pseudo-4D triple resonance experiments to resolve HN overlap in the backbone assignment of unfolded proteins [Elektronische Daten] [Ireena Bagai, Stephen Ragsdale, Erik Zuiderweg] 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 15N-1HN cross peaks. For such residues, one cannot unambiguously link the "left” side of the NH root to the "right” side, and the residues associated with such overlapping HN resonances remain often unassigned. Here we present a solution to this problem: a hybrid (4d,3d) reduced-dimensionality HN(CO)CA(CON)CA sequence. In this experiment, the Ca(i) resonance is modulated with the frequency of the Ca(i−1) resonance, which helps in resolving the ambiguity involved in connecting the Ca(i) and Ca(i−1) resonances for overlapping NH roots. The experiment has limited sensitivity, and is only suited for small or unfolded proteins. In a companion experiment, (4d,3d) reduced-dimensionality HNCO(N)CA, the Ca(i) resonance is modulated with the frequency of the CO(i−1) resonance, hence resolving the ambiguity existent in pairing up the Ca(i) and CO(i−1) resonances for overlapping NH roots. Springer Science+Business Media B.V., 2010 Assignment nationallicence Unfolded proteins nationallicence Triple resonance nationallicence Reduced-dimensionality nationallicence Bagai Ireena Department of Biological Chemistry, University of Michigan Medical School, MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut Ragsdale Stephen Department of Biological Chemistry, University of Michigan Medical School, MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut Zuiderweg Erik Department of Biological Chemistry, University of Michigan Medical School, 4220D MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut Journal of Biomolecular NMR Springer Netherlands 49/2(2011-02-01), 69-74 0925-2738 49:2<69 2011 49 10858 https://doi.org/10.1007/s10858-010-9465-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10858-010-9465-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Bagai Ireena Department of Biological Chemistry, University of Michigan Medical School, MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut NATIONALLICENCE 700 1- Ragsdale Stephen Department of Biological Chemistry, University of Michigan Medical School, MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut NATIONALLICENCE 700 1- Zuiderweg Erik Department of Biological Chemistry, University of Michigan Medical School, 4220D MSRB III, 1150W. Medical Center Drive, 48109-5605, Ann Arbor, MI, USA aut NATIONALLICENCE 773 0- Journal of Biomolecular NMR Springer Netherlands 49/2(2011-02-01), 69-74 0925-2738 49:2<69 2011 49 10858 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer