1qu1
CRYSTAL STRUCTURE OF EHA2 (23-185)
OverviewOverview
The structure of a stable recombinant ectodomain of influenza hemagglutinin HA(2) subunit, EHA(2) (23-185), defined by proteolysis studies of the intact bacterial-expressed ectodomain, was determined to 1.9-A resolution by using x-ray crystallography. The structure reveals a domain composed of N- and C-terminal residues that form an N cap terminating both the N-terminal alpha-helix and the central coiled coil. The N cap is formed by a conserved sequence, and part of it is found in the neutral pH conformation of HA. The C-terminal 23 residues of the ectodomain form a 72-A long nonhelical structure ordered to within 7 residues of the transmembrane anchor. The structure implies that continuous alpha helices are not required for membrane fusion at either the N or C termini. The difference in stability between recombinant molecules with and without the N cap sequences suggests that additional free energy for membrane fusion may become available after the formation of the central triple-stranded coiled coil and insertion of the fusion peptide into the target membrane.
About this StructureAbout this Structure
1QU1 is a Single protein structure of sequence from Influenza a virus. The following page contains interesting information on the relation of 1QU1 with [Hemagglutinin]. Full crystallographic information is available from OCA.
ReferenceReference
N- and C-terminal residues combine in the fusion-pH influenza hemagglutinin HA(2) subunit to form an N cap that terminates the triple-stranded coiled coil., Chen J, Skehel JJ, Wiley DC, Proc Natl Acad Sci U S A. 1999 Aug 3;96(16):8967-72. PMID:10430879 Page seeded by OCA on Sat May 3 06:42:20 2008