Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2008 Feb 26;105(8):2800-5. doi: 10.1073/pnas.0711963105. Epub 2008 Feb 19.

Quantitative biochemical rationale for differences in transmissibility of 1918 pandemic influenza A viruses.

Author information

1
Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.

Abstract

The human adaptation of influenza A viruses is critically governed by the binding specificity of the viral surface hemagglutinin (HA) to long (chain length) alpha2-6 sialylated glycan (alpha2-6) receptors on the human upper respiratory tissues. A recent study demonstrated that whereas the 1918 H1N1 pandemic virus, A/South Carolina/1/1918 (SC18), with alpha2-6 binding preference transmitted efficiently, a single amino acid mutation on HA resulted in a mixed alpha2-3 sialylated glycan (alpha2-3)/alpha2-6 binding virus (NY18) that transmitted inefficiently. To define the biochemical basis for the observed differences in virus transmission, in this study, we have developed an approach to quantify the multivalent HA-glycan interactions. Analysis of the molecular HA-glycan contacts showed subtle changes resulting from the single amino acid variations between SC18 and NY18. The effect of these changes on glycan binding is amplified by multivalency, resulting in quantitative differences in their long alpha2-6 glycan binding affinities. Furthermore, these differences are also reflected in the markedly distinct binding pattern of SC18 and NY18 HA to the physiological glycans present in human upper respiratory tissues. Thus, the dramatic lower binding affinity of NY18 to long alpha2-6 glycans, as against a mixed alpha2-3/6 binding, correlates with its inefficient transmission. In summary, this study establishes a quantitative biochemical correlate for influenza A virus transmission.

PMID:
18287068
PMCID:
PMC2268540
DOI:
10.1073/pnas.0711963105
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center