Drs. Bossche vs Raszek 2-0
We do another super deep dive into the latest evolution of the virus to inquire if Dr. Bossche theory of the pandemic evolution becoming more deadly is supported by the latest emerging information or not!
Discussion includes:
*Why is SARS-CoV-2 evolution so insane
*What is protein glycosylation
*Detailed look at the evolutionary tree of coronaviruses
*What are the unusual results of the latest sugar attachments to spike protein
*How is the virus evolving in unusual ways to find new ways to infect us
*What does this mean for potential virus pathogenicity
ABSTRACT OF STUDY DISCUSSED
Selective pressures have given rise to a number of SARS-CoV-2 variants during the prolonged course of the COVID-19 pandemic. Recently evolved variants differ from ancestors in additional glycosylation within the spike protein receptor-binding domain (RBD). Details of how the acquisition of glycosylation impacts viral fitness and human adaptation are not clearly understood. Here, we dissected the role of N354-linked glycosylation, acquired by BA.2.86 sub-lineages, as a RBD conformational control element in attenuating viral infectivity. The reduced infectivity is recovered in the presence of heparin sulfate, which targets the ‘N354 pocket’ to ease restrictions of conformational transition resulting in a ‘RBD-up’ state, thereby conferring an adjustable infectivity. Furthermore, N354 glycosylation improved spike cleavage and cell–cell fusion, and in particular escaped one subset of ADCC antibodies. Together with reduced immunogenicity in hybrid immunity background, these indicate a single spike amino acid glycosylation event provides selective advantage in humans through multiple mechanisms.
https://academic.oup.com/nsr/article/11/7/nwae206/7693733?login=false