Molecular mechanisms of HipA-mediated multidrug tolerance and its neutralization by HipB.
Schumacher, M.A., Piro, K.M., Xu, W., Hansen, S., Lewis, K., Brennan, R.G.(2009) Science 323: 396-401
- PubMed: 19150849 
- DOI: https://doi.org/10.1126/science.1163806
- Primary Citation of Related Structures:  
3DNT, 3DNU, 3DNV, 3FBR, 3HZI - PubMed Abstract: 
Bacterial multidrug tolerance is largely responsible for the inability of antibiotics to eradicate infections and is caused by a small population of dormant bacteria called persisters. HipA is a critical Escherichia coli persistence factor that is normally neutralized by HipB, a transcription repressor, which also regulates hipBA expression. Here, we report multiple structures of HipA and a HipA-HipB-DNA complex. HipA has a eukaryotic serine/threonine kinase-like fold and can phosphorylate the translation factor EF-Tu, suggesting a persistence mechanism via cell stasis. The HipA-HipB-DNA structure reveals the HipB-operator binding mechanism, approximately 70 degrees DNA bending, and unexpected HipA-DNA contacts. Dimeric HipB interacts with two HipA molecules to inhibit its kinase activity through sequestration and conformational inactivation. Combined, these studies suggest mechanisms for HipA-mediated persistence and its neutralization by HipB.
Organizational Affiliation: 
Department of Biochemistry and Molecular Biology, University of Texas, M. D. Anderson Cancer Center, Unit 1000, Houston, TX 77030, USA. maschuma@mdanderson.org