These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Full-length influenza hemagglutinin HA2 refolds into the trimeric low-pH-induced conformation.
    Author: Swalley SE, Baker BM, Calder LJ, Harrison SC, Skehel JJ, Wiley DC.
    Journal: Biochemistry; 2004 May 18; 43(19):5902-11. PubMed ID: 15134464.
    Abstract:
    The influenza virus uses hemagglutinin (HA) to fuse the viral and cellular membranes. As part of an effort to study the membrane-interacting elements of HA, the fusion peptide, and the C-terminal transmembrane anchor, we have expressed in Escherichia coli the full-length HA(2) chain with maltose-binding protein fused at its N-terminus. The chimeric protein can be refolded in vitro in the presence of specific detergents to yield stable, homogeneous trimers, as determined by analytical ultracentrifugation. The trimers have the so-called "low pH" conformation-the rearranged HA(2) conformation obtained when intact HA(1)/HA(2) is induced to refold by exposure to low pH-as detected by electron microscopy and monoclonalantibody reactivity. These results provide further evidence for the notion that the neutral-pH structure of intact HA is metastable and that binding of protons lowers the kinetic barriers that prevent rearrangement to the minimum-free-energy conformation. The refolded chimeric protein described here is a suitable species for undertaking studies of how the fusion peptide inserts into membranes and assessing the nature of possible intermediates in the fusion process.
    [Abstract] [Full Text] [Related] [New Search]