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Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins

We present a strategy for stereospecific NMR assignment of H(β2) and H(β3) protons in mid-size proteins (~150 residues). For such proteins, resonance overlap in standard experiments is severe, thereby preventing unambiguous assignment of a large fraction of β-methylenes. To alleviate this limitation...

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Autores principales: Born, Alexandra, Henen, Morkos A., Nichols, Parker, Wang, Jing, Jones, David N., Vögeli, Beat
Formato: Online Artículo Texto
Lenguaje:English
Publicado: 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6513325/
https://www.ncbi.nlm.nih.gov/pubmed/31093488
http://dx.doi.org/10.3390/magnetochemistry4020025
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author Born, Alexandra
Henen, Morkos A.
Nichols, Parker
Wang, Jing
Jones, David N.
Vögeli, Beat
author_facet Born, Alexandra
Henen, Morkos A.
Nichols, Parker
Wang, Jing
Jones, David N.
Vögeli, Beat
author_sort Born, Alexandra
collection PubMed
description We present a strategy for stereospecific NMR assignment of H(β2) and H(β3) protons in mid-size proteins (~150 residues). For such proteins, resonance overlap in standard experiments is severe, thereby preventing unambiguous assignment of a large fraction of β-methylenes. To alleviate this limitation, assignment experiments may be run in high static fields, where higher decoupling power is required. Three-bond H(α)–H(β) J-couplings ((3)J(Hα–Hβ)) are critical for stereospecific assignments of β-methylene protons, and for determining rotameric χ(1) states. Therefore, we modified a pulse sequence designed to measure accurate (3)J(Hα–Hβ) couplings such that probe heating was reduced, while the decoupling performance was improved. To further increase the resolution, we applied non-uniform sampling (NUS) schemes in the indirect (1)H and (13)C dimensions. The approach was applied to two medium-sized proteins, odorant binding protein 22 (OBP22; 14.4 kDa) and Pin1 (18.2 kDa), at 900 MHz polarizing fields. The coupling values obtained from NUS and linear sampling were extremely well correlated. However, NUS decreased the overlap of H(β2/3) protons, thus supplying a higher yield of extracted (3)J(Hα-Hβ) coupling values when compared with linear sampling. A similar effect could be achieved with linear prediction applied to the linearly sampled data prior to the Fourier transformation. Finally, we used (3)J(Hα–Hβ) couplings from Pin1 in combination with either conventional or exact nuclear Overhauser enhancement (eNOE) restraints to determine the stereospecific assignments of β-methylene protons. The use of eNOEs further increased the fraction of unambiguously assigned resonances when compared with procedures using conventional NOEs.
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spelling pubmed-65133252019-05-13 Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins Born, Alexandra Henen, Morkos A. Nichols, Parker Wang, Jing Jones, David N. Vögeli, Beat Magnetochemistry Article We present a strategy for stereospecific NMR assignment of H(β2) and H(β3) protons in mid-size proteins (~150 residues). For such proteins, resonance overlap in standard experiments is severe, thereby preventing unambiguous assignment of a large fraction of β-methylenes. To alleviate this limitation, assignment experiments may be run in high static fields, where higher decoupling power is required. Three-bond H(α)–H(β) J-couplings ((3)J(Hα–Hβ)) are critical for stereospecific assignments of β-methylene protons, and for determining rotameric χ(1) states. Therefore, we modified a pulse sequence designed to measure accurate (3)J(Hα–Hβ) couplings such that probe heating was reduced, while the decoupling performance was improved. To further increase the resolution, we applied non-uniform sampling (NUS) schemes in the indirect (1)H and (13)C dimensions. The approach was applied to two medium-sized proteins, odorant binding protein 22 (OBP22; 14.4 kDa) and Pin1 (18.2 kDa), at 900 MHz polarizing fields. The coupling values obtained from NUS and linear sampling were extremely well correlated. However, NUS decreased the overlap of H(β2/3) protons, thus supplying a higher yield of extracted (3)J(Hα-Hβ) coupling values when compared with linear sampling. A similar effect could be achieved with linear prediction applied to the linearly sampled data prior to the Fourier transformation. Finally, we used (3)J(Hα–Hβ) couplings from Pin1 in combination with either conventional or exact nuclear Overhauser enhancement (eNOE) restraints to determine the stereospecific assignments of β-methylene protons. The use of eNOEs further increased the fraction of unambiguously assigned resonances when compared with procedures using conventional NOEs. 2018-06-01 2018-06 /pmc/articles/PMC6513325/ /pubmed/31093488 http://dx.doi.org/10.3390/magnetochemistry4020025 Text en Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Born, Alexandra
Henen, Morkos A.
Nichols, Parker
Wang, Jing
Jones, David N.
Vögeli, Beat
Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title_full Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title_fullStr Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title_full_unstemmed Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title_short Efficient Stereospecific H(β2/3) NMR Assignment Strategy for Mid-Size Proteins
title_sort efficient stereospecific h(β2/3) nmr assignment strategy for mid-size proteins
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6513325/
https://www.ncbi.nlm.nih.gov/pubmed/31093488
http://dx.doi.org/10.3390/magnetochemistry4020025
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