Crystal Structure of HiaBD1

Experimental Data Snapshot

  • Resolution: 2.10 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.217 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


Structural basis for host recognition by the Haemophilus influenzae Hia autotransporter.

Yeo, H.J.Cotter, S.E.Laarmann, S.Juehne, T.St Geme, J.W.Waksman, G.

(2004) EMBO J 23: 1245-1256

  • DOI: https://doi.org/10.1038/sj.emboj.7600142
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Haemophilus influenzae is an important human pathogen that initiates infection by colonizing the upper respiratory tract. The H. influenzae Hia autotransporter is an adhesive protein that promotes adherence to respiratory epithelial cells. Hia adhesive activity resides in two homologous binding domains, called HiaBD1 and HiaBD2. These domains interact with the same host cell receptor, but bind with different affinities. In this report, we describe the crystal structure of the high-affinity HiaBD1 binding domain, which has a novel trimeric architecture with three-fold symmetry and a mushroom shape. The subunit constituents of the trimer are extensively intertwined. The receptor-binding pocket is formed by an acidic patch that is present on all three faces of the trimer, providing potential for a multivalent interaction with the host cell surface, analogous to observations with the trimeric tumor necrosis factor superfamily of proteins. Hia is a novel example of a bacterial trimeric adhesin and may be the prototype member of a large family of bacterial virulence proteins with a similar architecture.

  • Organizational Affiliation

    Institute of Structural Molecular Biology, Birkbeck and University College London, Malet Street, London, UK.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D, E
A, B, C, D, E, F
174Haemophilus influenzaeMutation(s): 0 
Gene Names: hia
Find proteins for Q48152 (Haemophilus influenzae)
Explore Q48152 
Go to UniProtKB:  Q48152
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ48152
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.10 Å
  • R-Value Free: 0.254 
  • R-Value Work: 0.217 
  • R-Value Observed: 0.217 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 83.582α = 90
b = 86.204β = 99.08
c = 89.119γ = 90
Software Package:
Software NamePurpose
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-04-06
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance