XBB.1.9.1 sublineage with S:G485S (>20 seq, UK)

[oobb45729]

Description
Sub-lineage of: XBB.1.9.1
Earliest sequence: 2023-02-17 (UK)
Most recent sequence: 2023-03-07 (UK)
Countries circulating: UK
Number of sequences: >10
Substitutions on top of XBB.1.9.1: T1753C then G23015A(S:G485S)

https://nextstrain.org/fetch/genome.ucsc.edu/trash/ct/subtreeAuspice1_genome_3fd2b_260020.json?c=gt-S_485&label=id:node_7687204

S:G485S used to be rare, but it has been increasing recently.

It was speculated by @Sinickle in #1510 that S:G485S and S:F486P might be synergistic.
I used AlphaFold to predict the interactions of F486P variant and F486P+G485S variant to ACE2.


The side chain of S485 of the G485S variant may form a hydrogen bond with the main chain of P486 or the side chain of C488 and slightly displace the position of P486, assisting the interaction of P486 to L79 and M82 of ACE2.
On the other hand, for variants with F486 like BA.2 (PDB: 7XB0), F486 mainly interact with M82 and Y83 of ACE2. The G485S mutation may draw F486 away from Y83 of ACE2, which may be undesirable for ACE2 binding.