In humans, P. aeruginosa infections are a cause of significant motility in Cystic Fibrosis patients. In P. aeruginosa there are many features of the bacterial cell that localize to the poles, and also contribute to the virulence of this organism. There are four chemotaxis-like systems, three of which are localized to the cell poles. Despite the similarities between these two-component signal transduction systems, they not only control different motility apparatus and virulence factors, they also have distinct sub-cellular addresses. The mechanisms of achieving and maintaining these distinct sub-cellular addresses is unknown, and characterizing this is one of the goals of this research. To this end, I will be studying the soluble methyl accepting chemotaxis proteins (IVICPs), BdIA and IVIcpS, and identifying their cognate chemotaxis systems, as well as their landmark or anchor proteins. This will be achieved using fluorescence microscopy, mutagenesis, and yeast two-hybrid assays. It is known that methylation of MCPs in E. coll affects the localization of some, but not all, MCPs. The mechanism of MCP methylation in P. aeruginosa remains unknown, as does the effect of methylation on MCP localization. These studies will comprise the second aim of this research, and will include mutagenesis, co-purification and methylation assays, along with immunofluorescence. Finally, I will identify and characterize novel proteins that show spatial sequestration within the P. aeruginosa ceil. I have developed a strain that divides asymmetrically, resulting in rods and minicells. The membranes of the these two cell types are being subjected to comparative proteomics using ITRAQ. As histidine kinases have been reported to affect the asymmetry of other bacteria, and P. aeruginosa is predicted to encode 63 histidine kinases, the emphasis of my research will be on histidine kinases with a polar localization pattern. Ultimately, I will be studying how polarity is achieved and maintained within the P. aeruginosa cell, and the effect these polar proteins have on not only the internal organization, but also the lifecycle and virulence of P. aeruginosa.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Transition Award (R00)
Project #
5R00GM083147-04
Application #
7923385
Study Section
Special Emphasis Panel (NSS)
Program Officer
Flicker, Paula F
Project Start
2007-12-01
Project End
2012-08-31
Budget Start
2010-09-01
Budget End
2011-08-31
Support Year
4
Fiscal Year
2010
Total Cost
$246,472
Indirect Cost
Name
University of Wisconsin Milwaukee
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
627906399
City
Milwaukee
State
WI
Country
United States
Zip Code
53201
Jansari, Vibhuti H; Potharla, Vishwakanth Y; Riddell, Geoff T et al. (2016) Twitching motility and cAMP levels: signal transduction through a single methyl-accepting chemotaxis protein. FEMS Microbiol Lett 363:
Ketelboeter, Laura M; Bardy, Sonia L (2015) Methods to Inhibit Bacterial Pyomelanin Production and Determine the Corresponding Increase in Sensitivity to Oxidative Stress. J Vis Exp :e53105
Ketelboeter, Laura M; M Ketelboeter, Laura; Potharla, Vishwakanth Y et al. (2014) NTBC treatment of the pyomelanogenic Pseudomonas aeruginosa clinical isolate PA1111 inhibits pigment production and increases sensitivity to oxidative stress. Curr Microbiol 69:343-8
Feriancikova, Lucia; Bardy, Sonia L; Wang, Lixia et al. (2013) Effects of outer membrane protein TolC on the transport of Escherichia coli within saturated quartz sands. Environ Sci Technol 47:5720-8
Walczak, Jacob J; Wang, Lixia; Bardy, Sonia L et al. (2012) The effects of starvation on the transport of Escherichia coli in saturated porous media are dependent on pH and ionic strength. Colloids Surf B Biointerfaces 90:129-36
Walczak, Jacob J; Bardy, Sonia L; Feriancikova, Lucia et al. (2011) Comparison of the Transport of Tetracycline-Resistant and Tetracycline-Susceptible Escherichia coli Isolated from Lake Michigan. Water Air Soil Pollut 222:305-314
Walczak, Jacob J; Bardy, Sonia L; Feriancikova, Lucia et al. (2011) Influence of tetracycline resistance on the transport of manure-derived Escherichia coli in saturated porous media. Water Res 45:1681-90