canping-huang-phd-novel-virus-discovery-in-bat-isn-translation

2.2.2 The Characteristics of the Structure of HKU9 Spike Protein and HKU9-RBD
Sequence
We used bioinformatics to analyze the sequence of the S protein of BatCoV HKU9. The
length of the S Protein is 1274 amino acids, and it has typical coronavirus S protein
characteristics (for example, the characteristic heptad repeats 1 and 2 of the S2 subunit),
though it is predicted a furin-like protease cleavage site cuts the S protein into S1/S2
subunits. Our comparisons of full-length S protein found limited amino acid sequence
identity between the S protein of BatCoV HKU9 and other betacoronaviruses (the identity
with MERS-CoV S, HKU4 S and SARS-CoV S is 27.9%, 28.0% and 30.4% respectively).
However, as shown in Figure 2.3, we can make a prediction about the location of the RBD
based on the signature L(+)-Cysteine residue within the core subdomain. According to the
RBD structure [37, 79, 80, 95] we obtained, these residues can form 3 conservative disulfide
bonds to stabilize the folding of the core. The HKU9-RBD was located in residues spanning
355-521 of the S protein. The length of the core subdomain of HKU9-RBD is comparable to
that of other RBD sequences.
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A partial translation into English of the PhD thesis: “Novel Virus Discovery in Bat and the Exploration of
Receptor of Bat Coronavirus HKU9” by Canping Huang, Chinese Center for Disease Control and Prevention,
2016. Translation completed for Independent Science News in March 2021.