Deep sequencing reveals the viral adaptation process of environment-derived H10N8 in mice.
PMID: 26477933
2016
Infection, genetics and evolution
Abstract: Using Illumina high-throughput data, we detected the gradual mutations of F277S, C278Q, F611S and L653P in the polymerase acidic (PA) protein, and of L207V and E627K in the PB2 protein during adaptation.
Species difference in ANP32A underlies influenza A virus polymerase host restriction.
Abstract: Substitutions, such as PB2(E627K), were rapidly selected upon infection of humans with avian H5N1 or H7N9 influenza viruses, adapting the viral polymerase for the shorter mammalian ANP32A.
Introduction: Acquisition of host-adapting mutations, such as PB2 E627K, enables polymerase activity to be supported by the shorter ANP32 proteins typical of mammalian hosts.
Introduction: Each RH clone was screened for the ability to support activity of a H5N1 avian influenza virus polymerase (A/turkey/England/50-92/91 virus (50-92)) compared with its human-adapted isoform bearing PB2 E627K.
Introduction: In mammalian cells, the low activity of reconstituted avian virus polymerase can be significantly increased by a single amino acid substitution (
PB2-588 V promotes the mammalian adaptation of H10N8, H7N9 and H9N2 avian influenza viruses.
Introduction: One well-characterized mutation in PB2 is the glutamate change to lysine at position 627 (E627K) that results in efficient virus replication in mammalian cells and enhanced virulence in mammals.
Discussion: Many adaptive mutations in PB2, such as E627K, D701N, K526R, and T271A have been proven to be important for different avian influenza viruses to break the host species barrier to infect mammals.
Discussion: Previous studies have shown that D701N and E627K may influence the interaction of PB2 with different isoforms of importin-alpha to adapt mammalian hosts and a recent study sh
Genomic Signatures for Avian H7N9 Viruses Adapting to Humans.
Conclusion: Numerous human-isolated avian influenza A viruses exhibit PB2 627K, which is a human-specific signature, and strong biological evidence indicates that an E627K mutation promotes avian viral replication in mammals.
Conclusion: We used a reporter assay to test all of these substitutions and showed that either Q591K, M535L, or D701N mutation increases the viral RNP activity in human cells with PB2 627E, suggesting that E627K, Q591K, M535L, and D701N are crucial markers for assessing the potential of an avian virus to infect humans, as well as for potentially increasing adaptation for the virus t
Amino acid substitutions occurring during adaptation of an emergent H5N6 avian influenza virus to mammals.
Abstract: We provide evidence that the mutations HA A150V, NA R143K and G147E, PB2 E627K, and PA A343T may be important for adaptation of H5N6 AIVs to mammals.
Multiple Natural Substitutions in Avian Influenza A Virus PB2 Facilitate Efficient Replication in Human Cells.
Abstract: Although substitutions like E627K in the PB2 polymerase subunit can facilitate polymerase activity to allow replication in mammals, many human H5N1 and H7N9 viruses lack this adaptive substitution.
Novel Polymerase Gene Mutations for Human Adaptation in Clinical Isolates of Avian H5N1 Influenza Viruses.
Abstract: A major determinant in the change of the avian influenza virus host range to humans is the E627K substitution in the PB2 polymerase protein.
Abstract: However, the polymerase activity of avian influenza viruses with a single PB2-E627K mutation is still lower than that of seasonal human influenza viruses, implying that avian viruses require polymerase mutations in addition to PB2-627K for human adaptation.
Discussion: A ferret-transmission experiment showed that an H5N1 virus acquired both HA and polymerase mutations during adaptation to a new host, even though the virus used in that study was a recombinant virus intentionally carrying the well-known adaptation mutations PB2-E627K and
Detection of reassortant avian influenza A (H11N9) virus in environmental samples from live poultry markets in China.
PMID: 27268229
2016
Infectious diseases of poverty
Table: E627K
Susceptibility and Status of Avian Influenza in Ostriches.
Abstract: Ostriches maintain a low upper- to midtracheal temperature as part of their adaptive physiology for desert survival, which may explain the selection in ratites for E627K or its compensatory mutations-markers that facilitate AIV replication at lower temperatures.
Abstract: Seventeen of 27 (63%) ostrich viruses contained the polymerase basic 2 (PB2) E627K marker, and 2 of the ostrich isolates that lacked E627K contained the compensatory Q591K mutation, whereas a third virus had a D701N mutation.
Prevailing PA Mutation K356R in Avian Influenza H9N2 Virus Increases Mammalian Replication and Pathogenicity.
Abstract: In addition, combined mutation of PA-K356R and PB2-E627K, a well-known mammalian adaptive marker, in the H9N2 virus showed further cooperative increases in virus production and severity of infection in vitro and in vivo In summary, PA-K356R behaves as a novel mammalian tropism mutation, which, along with other mutations such as PB2-E627K, might render avian H9N2 viruses adapted for human infection.
Abstract: We found that PA-356R in H9N2 viruses causes significant increases in virus replication and severity of infection in human cells and mice and that PA-K356R cooperates with the
ViMRT
IV mutation literature information.
PMID: 
2016
Infection, genetics and evolution
