SARS-CoV-2 spike protein interactions with model lipid bilayer membranes

Image courtesy of the ILL

The SARS-CoV-2 spike protein is know to bind with ACE2 receptors on cell surfaces (especially in the lungs) thus allowing the entry of the virus into human cells. Scientists from the Institut Laue-Langevin (ILL), in collaboration with the Institut de Biologie Structurale (IBS), the Paul Scherrer Institut (PSI) and the Australian Nuclear Science and Technology Organisation (ANSTO), focused on the interactions between the spike protein and the rest of the cell membrane. Several model cell membranes were created using supported lipid bilayers (SLBs), varying from single layers to more complex membrane structures. IBS successfully manufactured a stable SARS-CoV-2 spike protein (sSpike), containing the soluble part of the protein and the receptor-binding domain. This sSpike was then introduced so that interactions could be observed within the varying complexities of synthetic and natural membranes. The membranes were then studied at the ILL using neutron reflectometry, which permits sub-nanometer levels of resolution. Reserchers saw a degradation of the lipid bilayer as soon as sSpike was introduced (with and without the presence of sACE2). sSpike is able to significantly strip away lipids from the cell membrane, disrupting and potentially entering directly through the cell membrane. These fundamental research results, published in Scientific reports, could pave the way for further investigations and potential development of more effective therapeutics or future vaccines.

Lipid bilayer degradation induced by SARS-CoV-2 spike protein as revealed by neutron reflectometry. Luchini A, Micciulla S, Corucci G, Chaithanya Batchu K, Santamaria A, Laux V, Darwish T, Russell RA, Thepaut M, Bally I, Fieschi F, Fragneto G. Scientific Reports 11, 14867 (2021)

Contact : Franck Fieschi, UGA professor attached to the IBS (Membrane & Pathogens group)