The goal of this research program is to develop a mechanistic understanding of the general stress response (GSR) signaling system in the select agent pathogen, Brucella abortus. Our preliminary data demonstrate that this signaling system controls environmental stress adaptation and chronic infection in a mammalian infection model. B. abortus GSR signaling is controlled in part by the PhyR protein, a conserved regulator of adaptation to environmental stress that is broadly conserved in the ?-proteobacterial clade. PhyR contains an amino terminal ECF ?-like domain and a carboxy-terminal TCS receiver domain. Phosphorylation activates PhyR as an anti-anti-? factor and releases the classical ECF ? factor, ?E1 to directly regulate gene expression during stress. Our multi-disciplinary investigation of PhyR, ?E1 and other components of the GSR signaling system will define the mechanistic underpinnings of general stress signaling in a pathogen of significant human health, agricultural, and biodefense import. Moreover, the experiments proposed herein have the potential to inform new treatments for ?-proteobacterial disease such as brucellosis. As mentioned above, this proposal is highly multi-disciplinary, spanning genetics, biochemistry, molecular biophysics, cell biology, and whole-animal infection studies. I will conduct these studies with a team of three experienced postdoctoral fellows, all of whom have expertise working on this BSL3 select agent in containment at the University of Chicago Howard Taylor Ricketts Regional Biocontainment Laboratory.
The specific aims of this project are: 1) Define the role of the sensor histidine kinase, LovhK, as a GSR stress sensor, and characterize the molecular basis of stress signal detection by LovhK. 2) Define signals that activate the B. abortus general stress response in vitro and in a mammalian infection model. 3) Elucidate the structural mechanism of GSR activation.
Bacterial cells must detect and adapt to a broad range of chemical and physical signals in their environment to survive. Understanding the regulatory mechanisms that govern adaptive cellular responses can greatly impact our ability to manipulate and control bacterial growth. This project focuses on characterization of a conserved stress signaling system that controls survival of the pathogenic bacterium, Brucella abortus, inside its mammalian host.
|CzyÅ¼, Daniel M; Jain-Gupta, Neeta; Shuman, Howard A et al. (2016) A dual-targeting approach to inhibit Brucella abortus replication in human cells. Sci Rep 6:35835|
|Meyer, Peter A; Socias, Stephanie; Key, Jason et al. (2016) Data publication with the structural biology data grid supports live analysis. Nat Commun 7:10882|
|Herrou, Julien; CzyÅ¼, Daniel M; Willett, Jonathan W et al. (2016) WrpA Is an Atypical Flavodoxin Family Protein under Regulatory Control of the Brucella abortus General Stress Response System. J Bacteriol 198:1281-93|
|Willett, Jonathan W; Crosson, Sean (2016) Atypical modes of bacterial histidine kinase signaling. Mol Microbiol :|
|Willett, Jonathan W; Herrou, Julien; CzyÅ¼, Daniel M et al. (2016) Brucella abortus Î”rpoE1 confers protective immunity against wild type challenge in a mouse model of brucellosis. Vaccine 34:5073-81|
|Aakre, Christopher D; Herrou, Julien; Phung, Tuyen N et al. (2015) Evolving new protein-protein interaction specificity through promiscuous intermediates. Cell 163:594-606|
|Fiebig, Aretha; Herrou, Julien; Willett, Jonathan et al. (2015) General Stress Signaling in the Alphaproteobacteria. Annu Rev Genet 49:603-25|
|Willett, Jonathan W; Herrou, Julien; Briegel, Ariane et al. (2015) Structural asymmetry in a conserved signaling system that regulates division, replication, and virulence of an intracellular pathogen. Proc Natl Acad Sci U S A 112:E3709-18|
|Kim, Hye-Sook; Willett, Jonathan W; Jain-Gupta, Neeta et al. (2014) The Brucella abortus virulence regulator, LovhK, is a sensor kinase in the general stress response signalling pathway. Mol Microbiol 94:913-25|
|CzyÅ¼, Daniel M; Potluri, Lakshmi-Prasad; Jain-Gupta, Neeta et al. (2014) Host-directed antimicrobial drugs with broad-spectrum efficacy against intracellular bacterial pathogens. MBio 5:e01534-14|