Cryo-EM structures of SARS-CoV-2 BA.2-derived subvariants spike in complex with ACE2 receptor.

The monomeric human ACE2-PD exhibited binding to the RBDs of BA.2, BA.5, BA.2.75, BF.7, and XBB.1 with binding affinity ( I K i SB D sb ) of 4.80 ± 0.01, 3.2 ± 0.03, 1.2 ± 0.01, 4.1 ± 0.02, and 16.2 ± 0.03 nM, respectively. To investigate the potential role of glycans in this phenomenon, we compared the N-linked glycan profiles of RBDs to the corresponding S proteins across three subvariants: WT, BA.5, and XBB.1 (Supplementary Fig. To further analyze the RBD-PD interface in detail, we also determined the structures of monomeric RBDs (BA.2.75, BF.7, and XBB.1) bound to the ACE2-SIT1 complex. Additionally, the salt bridge formed by Arg493 of BA.2 with Glu35 of ACE2 is replaced by Gln493 in BA.2.75, BF.7, and XBB.1, reminiscent of the wild-type configuration (Fig. [Extracted from the article]