SARS-CoV-2 Spike RBD, His Tag (SPD-C5227) is expressed from human 293 cells (HEK293). It contains AA Arg 319 - Lys 537 (Accession # QHD43416.1 (L452Q, F490S)). Mutations L452Q, F490S were identified in the SARS-CoV-2 Lambda variant (Pango lineage: C.37).