Abstract: A novel variant of concern (VOC) named CAL.20C (B.1.427/B.1.429), which was originally detected in California, carries
spike glycoprotein mutations
S13I in the signal peptide,
W152C in the
N-terminal domain (NTD), and
L452R in the receptor-binding domain (
RBD).
Abstract: The
S13I and
W152C mutations resulted in total loss of neutralization for 10 of 10 NTD-specific mAbs because the NTD antigenic supersite was remodeled by a shift of the signal peptide cleavage site and the formation of a new disulfide bond, as revealed by mass spectrometry and structural studies.