Expression of enteropathogenic Escherichia coli map is significantly different than that of other type III secreted effectors in vivo Journal Article

Local Library Link: Find It @ Loyola

Authors: Nguyen, M.; Rizvi, J.; Hecht, G
Article Title: Expression of enteropathogenic Escherichia coli map is significantly different than that of other type III secreted effectors in vivo
Abstract: The enteropathogenic Escherichia coli (EPEC) locus of enterocyte effacement (LEE)-encoded effectors EspF and Map are multifunctional and have an impact on the tight junction barrier while the non-LEE-encoded proteins NleH1 and NleH2 possess significant anti-inflammatory activity. In order to address the temporal expression of these important genes in vivo, their promoters were cloned upstream of the luxCDABE operon, and luciferase expression was measured in EPEC-infected mice by bioluminescence using an in vivo imaging system (IVIS). Bioluminescent images of living mice, of excised whole intestines, and of whole intestines longitudinally opened and washed were assessed. The majority of bioluminescent bacteria localized in the cecum by 3 h postinfection, indicating that the cecum is not only a major colonization site of EPEC but also a site of EPEC effector gene expression in mice. espF, nleH1, and nleH2 were abundantly expressed over the course of infection. In contrast, map expression was suppressed at 2 days postinfection, and at 4 days postinfection it was totally abolished. After 2 to 4 days postinfection, when map is suppressed, EPEC colonization is significantly reduced, indicating that map may be one of the factors required to maintain EPEC colonization. This was confirmed in a competitive colonization study and in two models of chronic infection, repeated exposure to ketamine and Citrobacter rodentium infection. Our data suggest that map expression contributes to the maintenance of EPEC colonization.
Journal Title: Infection and immunity
Volume: 83
Issue: 1
ISSN: 1098-5522; 0019-9567
Publisher: American Society for Microbiology. All Rights Reserved  
Journal Place: United States
Date Published: 2015
Start Page: 130
End Page: 137
Language: eng
DOI/URL:

10.1128/IAI.02467-14
Notes: LR: 20150701; CI: Copyright (c) 2015; GR: DK050694/DK/NIDDK NIH HHS/United States; GR: R01 DK097043/DK/NIDDK NIH HHS/United States; GR: R01DK097043/DK/NIDDK NIH HHS/United States; JID: 0246127; 0 (Escherichia coli Proteins); 0 (Map protein, E coli); EC 1.13.12.- (Luciferases); OID: NLM: PMC4288863; 2014/10/13 [aheadofprint]; ppublish