Molecular Mechanisms of HipA-Mediated Multidrug Tolerance and Its Neutralization by HipB

• Published in: Science (American Association for the Advancement of Science) Vol. 323; no. 5912; pp. 396 - 401
• Main Authors: Schumacher, Maria A, Piro, Kevin M, Xu, Weijun, Hansen, Sonja, Lewis, Kim, Brennan, Richard G
• Format: Journal Article
• Language: English
• Published: United States American Association for the Advancement of Science 16.01.2009; The American Association for the Advancement of Science
• Subjects: Active sites; Adenosine Triphosphate - metabolism; Antibiotics; Antitoxins; Atoms; Crystallization; Crystallography, X-Ray; Dimerization; Dimers; DNA; DNA, Bacterial - chemistry; DNA, Bacterial - metabolism; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Drug Tolerance; Escherichia coli; Escherichia coli - chemistry; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - antagonists & inhibitors; Escherichia coli Proteins - chemistry; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Hydrogen bonds; Models, Molecular; Molecules; Nucleic Acid Conformation; Operator Regions, Genetic; Operon; Peptide Elongation Factor Tu - metabolism; Phosphorylation; Protein Conformation; Protein Folding; Protein Kinase Inhibitors - metabolism; Protein Kinases - chemistry; Protein Kinases - metabolism; Protein Structure, Secondary; Protein Structure, Tertiary; Proteins; Toxins
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1163806

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, ~70° 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.