caa a22 4500 477136036 CHVBK 20180405111718.0 cr unu---uuuuu 170330e19971201xx s 000 0 eng 10.1023/A:1018315729609 doi (NATIONALLICENCE)springer-10.1023/A:1018315729609 A simple method to quantitatively measure polypeptide JHNHα coupling constants from TOCSY or NOESY spectra [Elektronische Daten] [Yunjun Wang, Alex Nip, David Wishart] A simple linear relationship between the J $$_{_H N_H \alpha }$$ coupling constant and the linewidth (Δν1/2) of in-phase NMR peaks has been identified. This relationship permits the rapid and accurate determination of polypeptide J $$_{_H N_H \alpha }$$ coupling constants from a simple inspection of amide cross peaks in homonuclear 1H TOCSY or 1H NOESY spectra. By using the appropriate set of processing parameters we show that J $$_{_H N_H \alpha }$$ = 0.5(Δν1/2) − MW/5000 + 1.8 for TOCSY spectra and J $$_{_H N_H \alpha }$$ = 0.6(Δν1/2) − MW/5000 − 0.9 for NOESY spectra, where Δν1/2 is the half-height linewidth in Hz and MW is the molecular weight of the protein in Da. The simplicity of this relationship, combined with the ease with which Δν1/2 measurements can be made, means that J $$_{_H N_H \alpha }$$ coupling constants can now be rapidly determined (up to 100 measurements in less than 30 min) without the need for any complex curve-fitting algorithms. Tests on 11 different polypeptides involving more than 650 separate J $$_{_H N_H \alpha }$$ measurements have shown that this method yields coupling constants with an rmsd error (relative to X-ray data) of less than 0.9 Hz. Furthermore, the correlation coefficient between the predicted NMR coupling constants and those derived from high-resolution X-ray crystal structures is typically better than 0.89. These simple linear relationships have been found to be valid for peptides as small as 1 kDa to proteins as large as 20 kDa. Despite the method's simplicity, these results are comparable to the accuracy and precision of the best techniques published to date. Kluwer Academic Publishers, 1997 Coupling constant nationallicence Linewidth nationallicence TOCSY nationallicence NOESY nationallicence Wang Yunjun Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut Nip Alex Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut Wishart David Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut Journal of Biomolecular NMR Kluwer Academic Publishers 10/4(1997-12-01), 373-382 0925-2738 10:4<373 1997 10 10858 https://doi.org/10.1023/A:1018315729609 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1018315729609 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wang Yunjun Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut NATIONALLICENCE 700 1- Nip Alex Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut NATIONALLICENCE 700 1- Wishart David Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, T6G 2N8, Edmonton, AB, Canada aut NATIONALLICENCE 773 0- Journal of Biomolecular NMR Kluwer Academic Publishers 10/4(1997-12-01), 373-382 0925-2738 10:4<373 1997 10 10858 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer