Fig. 2: Monitoring SARS-CoV-2 MBP binding to lipid bilayers using AFM-based SMFS.

a Formation of lipid bilayers on mica support (top). Lipid vesicles were adsorbed onto freshly cleaved mica surface, forming lipid bilayers. AFM was used to obtain the height topography of DOPC/Chol bilayers, and the height cross-section profile was extracted from the corresponding height image. b Schematic illustrating the binding of MBP to the lipid bilayers monitored by AFM-based SMFS. Representative force vs time (FT) curves showing the binding of MBP1 into the lipid bilayers (indicated by black arrowhead). MBP2 did not exhibit binding events with the lipid bilayers. Representative FT curves of MBP1 binding to the DOPC/Chol membrane (c) or DOPC/SM membrane (d). Two distinct states (unbound: grey; bound: cyan/blue) were detected in the FT curves which were identified using the STaSI algorithm (red line) and depicted as histograms fitted using a multipeak Gaussian fit. Data points are color-coded based on the assignment by the STaSI model: gray dots represent the unbound state and cyan/blue dots the bound state. Source data for panels a-d are provided as a Source Data file. Data are representative of at least three independent replicates.