SARS-CoV-2 S1 protein NTD, His Tag (S1D-C52Hc) is expressed from human 293 cells (HEK293). It contains AA Ser 13 - Leu 303 (Accession # QHD43416.1). The L18F/D80A/D215G/LAL242-244del/R246I mutations were identified on the spike protein N-terminal domain (NTD) in the SARS-CoV-2 Beta variant (Pango lineage: B.1.351; other names: 20H/501Y.V2).