The Solution structure of HI1450

Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 65 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation   3D Report Full Report

This is version 1.4 of the entry. See complete history


Solution structure of the highly acidic protein HI1450 from Haemophilus influenzae, a putative double-stranded DNA mimic.

Parsons, L.M.Yeh, D.C.Orban, J.

(2004) Proteins 54: 375-383

  • DOI: https://doi.org/10.1002/prot.10607
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    The solution structure of the acidic protein HI1450 from Haemophilus influenzae has been determined by NMR spectroscopy. HI1450 has homologues in ten other bacterial species including Escherichia coli, Vibrio cholerae, and Yersinia pestis but there are no functional assignments for any members of the family. Thirty-one of the amino acids in this 107-residue protein are aspartates or glutamates, contributing to an unusually low pI of 3.72. The secondary structure elements are arranged in an alpha-alpha-beta-beta-beta-beta order with the two alpha helices packed against the same side of an anti-parallel four-stranded beta meander. Two large loops, one between beta1 and beta2 and the other between beta2 and beta3 bend almost perpendicularly across the beta-strands in opposite directions on the non-helical side of the beta-sheet to form a conserved hydrophobic cavity. The HI1450 structure has some similarities to the structure of the double-stranded DNA (dsDNA) mimic uracil DNA glycosylase inhibitor (Ugi) including the distribution of surface charges and the position of the hydrophobic cavity. Based on these similarities, as well as having a comparable molecular surface to dsDNA, we propose that HI1450 may function as a dsDNA mimic in order to inhibit or regulate an as yet unidentified dsDNA binding protein.

  • Organizational Affiliation

    Center for Advanced Research in Biotechnology, University of Maryland Biotechnology Institute, Rockville, Maryland 20850, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Hypothetical protein HI1450110Haemophilus influenzaeMutation(s): 0 
Gene Names: HI1450
Find proteins for P44199 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd))
Explore P44199 
Go to UniProtKB:  P44199
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP44199
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 65 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-01-27
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-02-23
    Changes: Data collection, Database references, Derived calculations
  • Version 1.4: 2024-05-22
    Changes: Data collection