Enhanced Escherichia coli adherence and invasion in Crohn’s disease and colon cancer 1 1The authors thank Professor T. K. Korhonen (Division of General Microbiology, University of Helsinki, Finland), who kindly donated Escherichia coli IH11165; Professor J.-F. Colombel (Laboratoire de Recherche sur les Maladies Inflammatoire de l’Intestine, Centre Hospitalier Universitaire, Lille, France) and Professor A. Darfeuille-Michaud (Faculte de Pharmacie, Clermont-Ferrand, France), who kindly donated the Crohn’s di

Martin, Helen; Campbell, Barry J.; Hart, C. A.; Mpofu, Chiedzo; Nayar, Manu; Singh, Ravinder; Englyst, Hans N.; Williams, H.; Rhodes, Jonathan M.

doi:10.1053/j.gastro.2004.03.054

Cited by 606 publications

(190 citation statements)

References 52 publications

Supporting

Mentioning

184

Contrasting

Order By: Relevance

“…Host inflammatory responses and intrinsic host genetic defects compromise mucosal and epithelial barrier integrity, enabling the enhanced proximity of mucosally associated bacteria to host cells. Consistent with this, enhanced intestinal tissue AIEC loads, mucosal association, and translocation (8,15,82) are correlated with more severe disease in CD and experimental models of colitis. Our study highlights the importance of environmental factors in altering AIEC physiology and subsequent host-microbe interactions and impact on inflammation.…”

Section: Discussionsupporting

confidence: 61%

Adherent-Invasive Escherichia coli Production of Cellulose Influences Iron-Induced Bacterial Aggregation, Phagocytosis, and Induction of Colitis

et al. 2015

View full text Add to dashboard Cite

Adherent-invasive Escherichia coli (AIEC), a functionally distinct subset of resident intestinal E. coli associated with Crohn's disease, is characterized by enhanced epithelial adhesion and invasion, survival within macrophages, and biofilm formation. Environmental factors, such as iron, modulate E. coli production of extracellular structures, which in turn influence the formation of multicellular communities, such as biofilms, and bacterial interactions with host cells. However, the physiological and functional responses of AIEC to variable iron availability have not been thoroughly investigated. We therefore characterized the impact of iron on the physiology of AIEC strain NC101 and subsequent interactions with macrophages. Iron promoted the cellulose-dependent aggregation of NC101. Bacterial cells recovered from the aggregates were more susceptible to phagocytosis than planktonic cells, which corresponded with the decreased macrophage production of the proinflammatory cytokine interleukin-12 (IL-12) p40. Prevention of aggregate formation through the disruption of cellulose production reduced the phagocytosis of iron-exposed NC101. In contrast, under iron-limiting conditions, where NC101 aggregation is not induced, the disruption of cellulose production enhanced NC101 phagocytosis and decreased macrophage secretion of IL-12 p40. Finally, abrogation of cellulose production reduced NC101 induction of colitis when NC101 was monoassociated in inflammation-prone Il10 ؊/؊ mice. Taken together, our results introduce cellulose as a novel physiological factor that impacts host-microbe-environment interactions and alters the proinflammatory potential of AIEC.

show abstract

Section: Discussionsupporting

confidence: 61%

Adherent-Invasive Escherichia coli Production of Cellulose Influences Iron-Induced Bacterial Aggregation, Phagocytosis, and Induction of Colitis

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Most E. coli strains isolated from the ileal mucosa of CD patients are able to adhere to and invade intestinal epithelial cells (14)(15)(16) and belong to the pathogenic group of adherent invasive E. coli (AIEC) (17). AIEC is highly associated with the ileal mucosa in CD patients (14)(15)(16)(18)(19)(20)(21)(22)(23).…”

mentioning

confidence: 99%

Ribonucleotide Reductase NrdR as a Novel Regulator for Motility and Chemotaxis during Adherent-Invasive Escherichia coli Infection

et al. 2015

View full text Add to dashboard Cite

A critical step in the life cycle of all organisms is the duplication of the genetic material during cell division. Ribonucleotide reductases (RNRs) are essential enzymes for this step because they control the de novo production of the deoxyribonucleotides required for DNA synthesis and repair. Enterobacteriaceae have three functional classes of RNRs (Ia, Ib, and III), which are transcribed from separate operons and encoded by the genes nrdAB, nrdHIEF, and nrdDG, respectively. Here, we investigated the role of RNRs in the virulence of adherent-invasive Escherichia coli (AIEC) isolated from Crohn's disease (CD) patients. Interestingly, the LF82 strain of AIEC harbors four different RNRs (two class Ia, one class Ib, and one class III). Although the E. coli RNR enzymes have been extensively characterized both biochemically and enzymatically, little is known about their roles during bacterial infection. We found that RNR expression was modified in AIEC LF82 bacteria during cell infection, suggesting that RNRs play an important role in AIEC virulence. Knockout of the nrdR and nrdD genes, which encode a transcriptional regulator of RNRs and class III anaerobic RNR, respectively, decreased AIEC LF82's ability to colonize the gut mucosa of transgenic mice that express human CEACAM6 (carcinoembryonic antigen-related cell adhesion molecule 6). Microarray experiments demonstrated that NrdR plays an indirect role in AIEC virulence by interfering with bacterial motility and chemotaxis. Thus, the development of drugs targeting RNR classes, in particular NrdR and NrdD, could be a promising new strategy to control gut colonization by AIEC bacteria in CD patients.R ibonucleotide reductase (RNR) is an essential enzyme in all living organisms. It catalyzes the reduction of ribonucleotides (nucleoside triphosphates [NTPs]) to their corresponding 2=-deoxyribonucleotides (deoxynucleoside triphosphates [dNTPs]) and therefore plays an essential role in DNA synthesis and repair. Three RNR classes (classes I, II, and III) exist; these classes exhibit different primary structures, subunit cofactor requirements, and quaternary three-dimensional (3D) structures, but they all are allosterically regulated and share similar catalytic mechanisms (1, 2). Class I RNRs are oxygendependent enzymes that occur in eubacteria, eukaryotes, and some viruses. This class comprises two main subgroups (Ia and Ib). Class Ia RNRs are encoded by an operon containing nrdA and nrdB genes. These genes encode the NrdA subunit, which is catalytically and allosterically regulated, and the NrdB subunit, which possesses radical-generating activity. Class Ib RNRs are encoded by an operon containing the nrdH, nrdI, nrdE, and nrdF genes, which encode the corresponding specific redoxin NrdH, the activating subunit NrdI, the catalytic subunit NrdE, and the radical-generating subunit NrdF. Class III RNRs are present in facultative anaerobic and strict anaerobic microorganisms and use S-adenosylmethionine and iron-sulfur clusters in the NrdG accessory protein to create a stab...

show abstract

“…Thus, there is an urgent need to develop detection methods in clinical setting to specifically differentiate and identified DAED strains accurately and also to discover its mode of transmission as well as responsible reservoir hosts. There are also limited data on the epidemiology of AIEC, however, it was suggested that AIEC is correlated with Crohn's disease (CD), which was evident in several clinical studies that found AIEC isolates in CD patients (Darfeuille-Michaud et al, 2004;Martin et al, 2004). With that, it is essential to carry out more clinical studies to further understand the transmission dynamics of AIEC globally, especially regarding its roles and connections with CD patients.…”

Section: Advances In Animal and Veterinary Sciencesmentioning

confidence: 99%