E. coli aconitase B structure reveals a HEAT-like domain with implications for protein-protein recognition.
Williams, C.H., Stillman, T.J., Barynin, V.V., Sedelnikova, S.E., Tang, Y., Green, J., Guest, J.R., Artymiuk, P.J.(2002) Nat Struct Biol 9: 447-452
- PubMed: 11992126 
- DOI: https://doi.org/10.1038/nsb801
- Primary Citation of Related Structures:  
1L5J - PubMed Abstract: 
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.
Organizational Affiliation: 
Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.