Secondary Structures of the Transmembrane Domain of SARS-CoV-2 Spike Protein in Detergent Micelles.

Qingxin Li,Qiwei Huang,Congbao Kang

doi:10.3390/ijms23031040

Abstract

Spike protein of SARS-CoV-2 contains a single-span transmembrane (TM) domain and plays roles in receptor binding, viral attachment and viral entry to the host cells. The TM domain of spike protein is critical for viral infectivity. Herein, the TM domain of spike protein of SARS-CoV-2 was reconstituted in detergent micelles and subjected to structural analysis using solution NMR spectroscopy. The results demonstrate that the TM domain of the protein forms a helical structure in detergent micelles. An unstructured linker is identified between the TM helix and heptapeptide repeat 2 region. The linker is due to the proline residue at position 1213. Side chains of the three tryptophan residues preceding to and within the TM helix important for the function of S-protein might adopt multiple conformations which may be critical for their function. The side chain of W1212 was shown to be exposed to solvent and the side chains of residues W1214 and W1217 are buried in micelles. Relaxation study shows that the TM helix is rigid in solution while several residues have exchanges. The secondary structure and dynamics of the TM domain in this study provide insights into the function of the TM domain of spike protein.

Highlights

The epidemic of novel coronavirus disease (COVID-19) started in late 2019
This disease is caused by a novel coronavirus which is named as severe acute respiratory syndrome coronavirus 2 (SAR-CoV-2)
SARS-CoV-2 belongs to beta-coronavirus which contains other important human pathogens such as SARSCoV which caused a viral outbreak in 2003 [4] and Middle East respiratory syndrome (MERS) coronavirus which was the cause of MERS in 2012 [5]

Summary

Introduction

The epidemic of novel coronavirus disease (COVID-19) started in late 2019. The lifestyles of people from many countries were affected as this disease can be spread through close contact. This disease is caused by a novel coronavirus which is named as severe acute respiratory syndrome coronavirus 2 (SAR-CoV-2). SARS-CoV-2 belongs to beta-coronavirus which contains other important human pathogens such as SARSCoV which caused a viral outbreak in 2003 [4] and Middle East respiratory syndrome (MERS) coronavirus which was the cause of MERS in 2012 [5]. Efforts have been made to develop vaccines and antivirals, which plays important roles in preventing viral spread

Methods

Results

Conclusion