E. coli aconitase B structure reveals a HEAT-like domain with implications for protein-protein recognition

Nat Struct Biol. 2002 Jun;9(6):447-52. doi: 10.1038/nsb801.


The major bifunctional aconitase of Escherichia coli (AcnB) serves as either an enzymic catalyst or a mRNA-binding post-transcriptional regulator, depending on the status of its iron sulfur cluster. AcnB represents a large, distinct group of Gram-negative bacterial aconitases that have an altered domain organization relative to mitochondrial aconitase and other aconitases. Here the 2.4 A structure of E. coli AcnB reveals a high degree of conservation at the active site despite its domain reorganization. It also reveals that the additional domain, characteristic of the AcnB subfamily, is a HEAT-like domain, implying a role in protein protein recognition. This domain packs against the remainder of the protein to form a tunnel leading to the aconitase active site, potentially for substrate channeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aconitate Hydratase / chemistry*
  • Aconitate Hydratase / metabolism*
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Cattle
  • Conserved Sequence
  • Crystallography, X-Ray
  • Escherichia coli / enzymology*
  • Models, Molecular
  • Molecular Sequence Data
  • Multienzyme Complexes / chemistry
  • Multienzyme Complexes / metabolism
  • Protein Binding
  • Protein Structure, Tertiary
  • RNA / metabolism
  • RNA-Binding Proteins / chemistry
  • RNA-Binding Proteins / metabolism
  • Sequence Alignment
  • Structure-Activity Relationship


  • Multienzyme Complexes
  • RNA-Binding Proteins
  • RNA
  • Aconitate Hydratase

Associated data

  • PDB/1L5J