Journal: bioRxiv

Article Title: Investigation of ACE2 N-terminal fragments binding to SARS-CoV-2 Spike RBD

doi: 10.1101/2020.03.19.999318

Figure Lengend Snippet: (A) RMSD for SBP1 docked to SARS-CoV-2-RBD during 200 ns MD simulation. (B) Binding interface between SARS-CoV-2-RBD and SBP1 after 200 ns simulation. Individual RMSD (C) and average RMSD (D) values for SBP1 residues over the course of the 200 ns simulation. Arrows indicate residues contributing key hydrogen bonding interactions (determined using UCSF Chimera, Version 1.12). Individual residues with RMSD below 5 Å arbitrarily colored green. (E) Binding affinity of SBP1 and a scrambled SBP1 sequence to various sources of glycosylated SARS-CoV-2-RBD proteins determined by bio-layer interferometry (BLI). (F) BLI association response of SBP1 to negative control human protein menin and (G) BLI association response of 12-mer SBP2 peptide to Sino Biological insect-derived SARS-CoV-2-RBD.

Article Snippet: However, competition was not observed when using non-biotinylated SBP1 pre141 mixed in solution with Sino Biological insect-derived SARS-CoV-2-RBD, even with a 1000-fold excess of the peptide ( ).

Techniques: Binding Assay, Sequencing, Negative Control, Derivative Assay

Journal: bioRxiv

Article Title: Investigation of ACE2 N-terminal fragments binding to SARS-CoV-2 Spike RBD

doi: 10.1101/2020.03.19.999318

Figure Lengend Snippet: (A) Association responses of biotinylated ACE2 to Sino Biological insect derived SARS-CoV-2-RBD at different concentrations. The kinetic dissociation constant determined under these conditions was K D , ACE2 = 15 nM. (B and D) Association responses of biotinylated ACE2 with Sino Biological insect-derived SARS-CoV-2-RBD (kept constant at 100 nM) after mixing with soluble human ACE2 at different concentrations. (B) shows the BLI traces and (D) shows re-plots of the endpoint association response (nm) as a function of ACE2 concentration. (C and E) Association responses of biotinylated ACE2 with Sino Biological insect-derived SARS-CoV-2-RBD (kept constant at 100 nM) after mixing with SBP1 at different concentrations. (C) shows the BLI traces and (E) shows re-plots of the endpoint association response (nm) as a function of SBP1 concentration.

Article Snippet: However, competition was not observed when using non-biotinylated SBP1 pre141 mixed in solution with Sino Biological insect-derived SARS-CoV-2-RBD, even with a 1000-fold excess of the peptide ( ).

Techniques: Derivative Assay, Concentration Assay

Journal: bioRxiv

Article Title: Investigation of ACE2 N-terminal fragments binding to SARS-CoV-2 Spike RBD

doi: 10.1101/2020.03.19.999318

Figure Lengend Snippet: Total ion current chromatograms (TIC) obtained by LC-MS analysis of commercial samples of (A) glycosylated Sino Biological HEK-expressed SARS-CoV-2-RBD (solution in phosphate-buffered saline) and (B) glycosylated Sino Biological insect-derived SARS-CoV-2-RBD with associated deconvoluted mass spectra obtained by integration over the protein peak at ~8 min. The broad bands in the TIC chromatograms of (B) are due to additives present in the vendor-formulated solid powder (10% glycerol, 5% trehalose, 5% mannitol and 0.01% tween-80).

Article Snippet: However, competition was not observed when using non-biotinylated SBP1 pre141 mixed in solution with Sino Biological insect-derived SARS-CoV-2-RBD, even with a 1000-fold excess of the peptide ( ).

Techniques: Liquid Chromatography with Mass Spectroscopy, Derivative Assay