Thread by @Biol4Ever

@K_G_Andersen Thank you so much for taking the time to lay down your arguments about this furin cleavage site. This is very useful and highly needed.
Yes, there is one aspect that you are missing, which has been bothering me:
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@K_G_Andersen This FCS was noted as "cleavage site" in a January 2020 publication by Zheng-Li Shi and colleagues (before the Nature paper):
"we predicted that the cleavage site for generating S1 and S2 subunits is located at R694/S695"
ncbi.nlm.nih.gov/pmc/articles/P…
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@K_G_Andersen Note that the correct position of the R/S furin cleavage site is 685/686 and not 694/695. There is no other RS amino acid sequence in the neighboring region so this "R694/S695" points to the furin cleavage site.
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@K_G_Andersen It is probable that they got the nucleotide position (694-695) wrong (shifted by 9 amino acids = 27 nucl.), due to assignment of an ATG start codon for the spike gene a little bit upstream (-27) of the correct one.
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@K_G_Andersen Why was this furin cleavage site, clearly an important and novel feature of the SARS-CoV-2 virus, not mentioned in the February 2020 Nature publication?
nature.com/articles/s4158…
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@K_G_Andersen Why does the alignment in the Nature paper stop right before the furin cleavage site? Why leaving a white space in the bottom right corner of this figure?
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@K_G_Andersen The Coutard et al. paper, submitted on 3 Feb 2020, shows an alignment with the furin cleavage site: see arrow "Site 1"
sciencedirect.com/science/articl…
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@K_G_Andersen Why was this furin cleavage site not mentioned by Zhou et al in their Nature paper? I hope that an answer will be provided to this question.
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