Cholera is a devastating diarrheal disease caused by Vibrio cholerae, a water-born pathogen. V. cholerae must adapt to changing nutrient availability, such as carbon sources, when transitioning between its aquatic reservoirs and the human host. Transcriptional analysis and mutagenesis screens have previously indicated that energy metabolism pathways, particularly the phosphoenolpyruvate (PEP)-carbohydrate phosphotransferase system (PTS), play a major role in the transition of V. cholerae between different niches. However, the components of the V. cholerae PTS remain largely uncharacterized. The long-term goal of this proposal is to elucidate how V. cholerae regulates the PTS to adapt to changing environments. Many small RNAs (sRNAs) are involved in diverse regulatory pathways involving stress-adaptation in V. cholerae and related bacteria. The objective of this proposal is to determine if an sRNA-mediated mechanism is involved in V. cholerae adaptation to different carbon sources. Previous studies have identified sRNAs in the V. cholerae transcriptome that may be involved in regulating the PTS of this facultative pathogen. Strong preliminary data suggests that an sRNA, MtlS, is expressed in a regulated manner and inhibits the expression of mtlA, the mannitol- specific transporter of V. cholerae. The central hypothesis is that V. cholerae uses MtlS-mediated control of gene expression to rapidly adapt to changes in carbon source, contributing to its environmental persistence. The central hypothesis will be tested by pursuing three specific aims. First, the mechanism of sRNA-mediated regulation of mannitol metabolism will be determined. Using biochemical approaches and mutagenesis, effects of MtlS on mtlA expression will be elucidated.
The second aim of this proposal will use dual genetic selections to identify minimal mtlA regulatory motifs targeted by MtlS.
The third aim of this proposal is to identify the regulator of mtlS expression using biochemical assays and mutagenesis. The experiments proposed here will advance the understanding of the role of sRNAs in carbon metabolism and elucidate components of a central metabolic pathway that may provide targets for vaccines and therapeutics against V. cholerae. Thus, the proposed research is relevant to the NIH's mission of developing fundamental knowledge that will reduce the burdens of human diseases. Furthermore, V. cholerae is an excellent model for other facultative bacteria;thus, this proposal will also provide insight into other known and emerging pathogens.

Public Health Relevance

This project involves determining how the bacterial pathogen Vibrio cholerae, the causative agent of cholera, adapts to different environments. With an estimated greater than one million cases each year, cholera represents a major global public health concern. Understanding the biochemical and physiological changes V. cholerae undergoes while transitioning between aquatic environment and host will provide insights into how we may combat these pathogens with next-generation therapeutics and vaccines.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Academic Research Enhancement Awards (AREA) (R15)
Project #
1R15AI090606-01
Application #
7980384
Study Section
Prokaryotic Cell and Molecular Biology Study Section (PCMB)
Program Officer
Hall, Robert H
Project Start
2010-06-15
Project End
2012-06-14
Budget Start
2010-06-15
Budget End
2012-06-14
Support Year
1
Fiscal Year
2010
Total Cost
$210,520
Indirect Cost
Name
Drew University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
002561868
City
Madison
State
NJ
Country
United States
Zip Code
07940
Page, Katharine; Shaffer, Jeremy; Lin, Samuel et al. (2018) Engineering Riboswitches in Vivo Using Dual Genetic Selection and Fluorescence-Activated Cell Sorting. ACS Synth Biol 7:2000-2006
Byer, Tanner; Wang, Jessica; Zhang, Mark G et al. (2017) MtlR negatively regulates mannitol utilization by Vibrio cholerae. Microbiology :
Chang, Howard; Replogle, John Michael; Vather, Naomi et al. (2015) A cis-regulatory antisense RNA represses translation in Vibrio cholerae through extensive complementarity and proximity to the target locus. RNA Biol 12:136-48
Mustachio, Lisa Maria; Aksit, Selime; Mistry, Ronak H et al. (2012) The Vibrio cholerae mannitol transporter is regulated posttranscriptionally by the MtlS small regulatory RNA. J Bacteriol 194:598-606