For other remaining entry-point residues of 449Y, 455L, 486F, 489Y and
500T, three residues 455L, 489Y and 500T of SARS-COV2 are identical to
both RatG13 and Pan_SL_COV_GD and did not need any nucleotides
substitution. But 449Y of SARS-COV2
(RaTG1,
aa F; Pan_SL_COV_GD, aa Y) could come directly from Pangolin
(aaY>aaY) or by a single nucleotide substitution from bat
(aaF>aaY, UUU > UAU, 2ndcodon, U>A). Similarly, for 486F (RaTG13 ,aa L;
Pan_SL_COV_GD , aa F), it can directly come from Pangolin or by a
single nucleotide substitution from RaTG13 (aaL > aaF, CUA
>CUU, 3rd codon A>U). Thus,
in 449Y and 486F both cases, a single nucleotide substitution from bat
can give rise to SARS-COV2 entry-point residues or they may come
directly from Pangolin by recombination(4).