Distinguishing Different Hydrogen-Bonded Helices in Proteins by Efficient 1H-Detected Three-Dimensional Solid-State NMR
Name
nihms-1965651.pdf
Description
Accepted version
Size
1.26 MB
Format
Adobe PDF
Checksum (MD5)
9c25c72ff9f55df9b0c9ff6ec9eab84c
Author(s)
Medeiros-Silva, Joao
Dregni, Aurelio J
Hong, Mei
Date Issued
December 21, 2023
Journal
Biochemistry
Publisher
American Chemical Society
Citation
Distinguishing Different Hydrogen-Bonded Helices in Proteins by Efficient 1H-Detected Three-Dimensional Solid-State NMR. Joao Medeiros-Silva, Aurelio J. Dregni, and Mei Hong. Biochemistry 2024 63 (1), 181-190.
Version
Author's final manuscript
Abstract
Helical structures in proteins include not only α-helices but also 310 and π helices. These secondary structures differ in the registry of the C═O···H–N hydrogen bonds, which are i to i + 4 for α-helices, i to i + 3 for 310 helices, and i to i + 5 for π-helices. The standard NMR observable of protein secondary structures are chemical shifts, which are, however, insensitive to the precise type of helices. Here, we introduce a three-dimensional (3D) 1H-detected experiment that measures and assigns CO–HN cross-peaks to distinguish the different types of hydrogen-bonded helices. This hCOhNH experiment combines efficient cross-polarization from CO to HN with 13C, 15N, and 1H chemical shift correlation to detect the relative proximities of the COi–Hi+jN spin pairs. We demonstrate this experiment on the membrane-bound transmembrane domain of the SARS-CoV-2 envelope (E) protein (ETM). We show that the C-terminal five residues of ETM form a 310-helix, whereas the rest of the transmembrane domain have COi–Hi+4N hydrogen bonds that are characteristic of α-helices. This result confirms the recent high-resolution solid-state NMR structure of the open state of ETM, which was solved in the absence of explicit hydrogen-bonding restraints. This C-terminal 310 helix may facilitate proton and calcium conduction across the hydrophobic gate of the channel. This hCOhNH experiment is generally applicable and can be used to distinguish not only different types of helices but also different types of β-strands and other hydrogen-bonded conformations in proteins.
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1021/acs.biochem.3c00589
