Spike protein s1 rbd

MG was purchased from ChemFaces (Wuhan, China). The SARS-CoV-2 spike/ACE2 inhibitor screening assay kit, biotin-labeled recombinant protein ACE2 receptor, and spike protein S1 RBD (BPS Bioscience, San Diego, CA, USA) were procured for biolayer interferometry. HEK293T cells stably expressing human ACE2 and TMPRSS2 cells were obtained from GeneCopoeia (Rockville, MD, USA) and maintained in Dulbecco’s modified Eagle’s medium (Lonza, Walkersville, MD, USA) containing 10% fetal bovine serum (Biotechnics Research, Lake Forest, CA, USA) and 1% penicillin/streptomycin (Cellgro, Manassas, VA, USA) at 37 °C in a 5% CO₂ incubator. Further, wild-type (WT) and mutant (D614G) SARS-CoV-2 spike pseudotyped viruses were purchased from GeneCopoeia (Rockville, MD, USA). Vero cells were purchased from American Type Culture Collection (Manassas, VA, USA). SARS-CoV-2 (βCoV/Korea/KCDC03/2020) was provided by Korea Centers for Disease Control and Prevention (Cheongju, Korea).

Geraniin (ChemFaces, Wuhan, China) was purchased. The SARS-CoV-2 spike: ACE2 inhibitor screening assay kit, biotin-labeled recombinant protein ACE2 receptor, and spike protein S1 RBD (BPS Bioscience, San Diego, CA, USA) for biolayer interferometry were procured.

KC was purchased from ChemFaces (Wuhan, China). The SARS-CoV-2 spike/ACE2 inhibitor screening assay kit, biotin-labeled recombinant protein ACE2 receptor, and spike protein S1 RBD (BPS Bioscience, San Diego, CA, USA) were purchased for the competitive ELISA assay and BLItz analysis. Human ACE2/TMPRSS2-overexpressing HEK293T stable cell line was purchased from GeneCopoeia (Rockville, MD, USA) and maintained in Dulbecco’s modified Eagle’s medium (Lonza, Walkersville, MD, USA) containing 10% fetal bovine serum (Biotechnics Research, Lake Forest, CA, USA) and 1% penicillin/streptomycin (Cellgro, Manassas, VA, USA) at 37 °C in a 5% CO₂ incubator. WT and mutant (D614G) SARS-CoV-2 spike pseudotyped viruses (cat. no. SP101-100 and SP103-100) were purchased from GeneCopoeia (Rockville, MD, USA). Vero cells were purchased from American Type Culture Collection (Manassas, VA, USA). A clinical isolate of SARS-CoV-2 alpha strain (βCoV/Korea/KCDC03/2020) was provided by Korea Centers for Disease Control and Prevention (Cheongju, Korea).