Table 1

Data collection and refinement statisticsa

ParameterValue for sw/Indiana00 HA
Data collection
    Wavelength (Å)0.97945
    Space groupP212121
    Unit cell parameters
        a, b, c (Å)93.4, 94.9, 220.5
        α, β, γ (°)90, 90, 90
    Resolution (Å)35–3.20 (3.31–3.20)
    No. of observations230,020
    No. of unique reflections32,867 (2,826)
    Completeness (%)98.2 (85.7)
    I/σ(I)11.0 (2.1)
    Rsymb0.17 (0.57)
Refinement statistics
    Resolution (Å)34.3-3.20
    No. of reflections (total)30,849
    No. of reflections (test)1,569
    Rcryst (%)d23.7d
    Rfree (%)e29.3e
    Avg B value (Å2)51.3
    Wilson B value (Å2)51.4
    No. of protein atoms11,530
    No. of carbohydrate atoms14
    No. of waters0
    RMSD from ideal geometryg
        Bond length (Å)0.006
        Bond angles (°)0.76
    Ramachandran statistics (%)f
  • a Data were collected using beamline SSRL 11-1. Numbers in parentheses refer to the highest-resolution shell. Structure data were deposited in the PDB under accession code 4F3Z.

  • b Rsym = Σhkl | <Ii> |/ΣhklIi, where Ii is the scaled intensity of the ith measurement of reflection (hkl) and <Ii> is the average intensity for that reflection.

  • c Za is the number of HA trimers per crystallographic asymmetric unit.

  • d Rcryst = Σhkl | FoFc |/Σhkl | Fo | × 100, where Fo and Fc are the observed and calculated structure factor amplitudes, respectively.

  • e Rfree was calculated as described for Rcryst but on a test set comprising 5% of the data excluded from refinement.

  • f Calculated using Molprobity (12).

  • g RMSD, root mean square deviation.