Alterations detected in the K22 resistant variants of HCoV-229E.

aDetected by comparison of the nucleotide sequences of HCoV-229E subjected to 10–13 passages in the presence of K22 including its plaque purified variants A-R with those of initial virus or mock-passaged virus (accession number KF293665).
bPlaque purified HCoV-229E that served as initial material for the virus passages.
cIC50 (µM).
dFold resistance to K22 as related to initial virus is shown in parentheses.
eVirus preparation and its plaque purified variants M-R obtained in separate K22 selection experiment.
fThe virus used for preparation of recombinant nsp6 mutants.
gK22 resistant recombinant viruses.