Abstract: Here we show that mutation
PB2-
K526R is present in some human H7N9 influenza isolates, in nearly 80% of H5N1 human isolates from Indonesia and, in conjunction with
E627K, in almost all seasonal H3N2 viruses since 1970.
Abstract: Host-adaptive strategies, such as the
E627K substitution in the
PB2 protein, are critical for replication of avian influenza A viruses in mammalian hosts.
Discussion: The
PB2 E627K substitution is recognized as a dominant adaptation marker in the majority of human-adapted influenza A viruses, facilitating replication in mammalian cells, however, the 590S/591R motif was found to complement the function of 627K in the
PB2 of 2009 H1N1 virus to allow replication i