Enteropathogenic E. coli (EPEC) is a common cause of severe, watery diarrhea in children in developing countries. EPEC is also the prototype of a group of attaching and effacing intestinal pathogens, including enterohemorrhagic E. coli (EHEC, such as O157:H7), Citrobacter rodentium, Hafnia alvei, and EPEC-like E. coli strains of domestic animals. Unlike many other E. coli strains that cause diarrhea, EPEC produces no known toxins, so the way it causes disease has been puzzling. Despite major advances in understanding how EPEC adhere, trigger cytoskeletal rearrangements in the host, and cause other host cell alterations, the mechanism by which EPEC causes diarrhea has been unclear. The discovery that EPEC triggers host cell death provided an important lead in how EPEC causes disease. The mode of cell death triggered by EPEC has features of both apoptosis (programmed cell death) and necrosis. One of the non-apoptotic features of EPEC-mediated killing is release of adenosine triphosphate (ATP) from the host cell. Once released, ATP is broken down to other adenine nucleotides and adenosine. Adenosine itself acts as a potent secretatagogue, i.e., a stimulator of intestinal fluid and electrolyte secretion, which may cause or contribute to watery diarrhea. The present application seeks to understand how EPEC triggers the ATP release from the host, with a particular focus on the role of the cystic fibrosis transmembrane regulator (CFTR). Other goals include determining the signaling pathways activated by adenosine which activate intestinal secretion, and the determining the extent of release of adenine nucleotides into the intestinal tract of rabbits infected with the EPEC-like pathogens rabbit diarrheagenic E. coli (RDEC-1) and rabbit EPEC (REPEC).

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI050652-03
Application #
6846597
Study Section
Bacteriology and Mycology Subcommittee 2 (BM)
Program Officer
Schmitt, Clare K
Project Start
2003-09-30
Project End
2007-01-31
Budget Start
2005-02-01
Budget End
2007-01-31
Support Year
3
Fiscal Year
2005
Total Cost
$274,750
Indirect Cost
Name
State University of New York at Buffalo
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
038633251
City
Buffalo
State
NY
Country
United States
Zip Code
14260
Crane, John K; Shulgina, Irina (2009) Feedback effects of host-derived adenosine on enteropathogenic Escherichia coli. FEMS Immunol Med Microbiol 57:214-28
Crane, John K; Naeher, Tonniele M; Shulgina, Irina et al. (2007) Effect of zinc in enteropathogenic Escherichia coli infection. Infect Immun 75:5974-84
Crane, J K; Vezina, C M (2005) Externalization of host cell protein kinase C during enteropathogenic Escherichia coli infection. Cell Death Differ 12:115-27
Crane, John K; Naeher, Tonniele M; Choudhari, Shilpa S et al. (2005) Two pathways for ATP release from host cells in enteropathogenic Escherichia coli infection. Am J Physiol Gastrointest Liver Physiol 289:G407-17