The Q226L mutation can convert a highly pathogenic H5 2.3.4.4e virus to bind human-type receptors.

H5Nx viruses continue to wreak havoc in avian and mammalian species worldwide. The virus distinguishes itself by the ability to replicate to high titers and transmit efficiently in a wide variety of hosts in diverse climatic environments. Fortunately, transmission to and between humans is scarce.

Chemoenzymatic Synthesis of Tri-antennary N-Glycans Terminating in Sialyl-Lewis Reveals the Importance of Glycan Complexity for Influenza A Virus Receptor Binding.

Sialyl-Lewis (SLe) is involved in immune regulation, human fertilization, cancer, and bacterial and viral diseases. The influence of the complex glycan structures, which can present SLe epitopes, on binding is largely unknown. We report here a chemoenzymatic strategy for the preparation of a panel of twenty-two isomeric asymmetrical tri-antennary N-glycans presenting SLe-Le epitopes on either the MGAT4 or MGAT5 arm that include putative high-affinity ligands for E-selectin.

Complex -glycans are important for interspecies transmission of H7 influenza A viruses.

Influenza A viruses (IAVs) can overcome species barriers by adaptation of the receptor-binding site of the hemagglutinin (HA). To initiate infection, HAs bind to glycan receptors with terminal sialic acids, which are either -acetylneuraminic acid (NeuAc) or -glycolylneuraminic acid (NeuGc); the latter is mainly found in horses and pigs but not in birds and humans. We investigated the influence of previously identified equine NeuGc-adapting mutations (S128T, I130V, A135E, T189A, and K193R) in avian H7 IAVs and .

Bioluminescent detection of viral surface proteins using branched multivalent protein switches.

Fast and reliable virus diagnostics is key to prevent the spread of viruses in populations. A hallmark of viruses is the presence of multivalent surface proteins, a property that can be harnessed to control conformational switching in sensor proteins. Here, we introduce a new sensor platform (dark-LUX) for the detection of viral surface proteins consisting of a general bioluminescent framework that can be post-translationally functionalized with separately expressed binding domains.