Cited by 156Escherichia coli research studiesEnterobacteriaceae and Cronobacter ResearchBacterial Genetics and Biotechnology

The Pic Protease of Enteroaggregative Escherichia coli Promotes Intestinal Colonization and Growth in the Presence of Mucin

Open access
Harrington, Susan M., Sheikh, Jalaluddin, Henderson, Ian R., Ruiz-Perez, Fernando, Cohen, Paul S., Nataro, James P.·2009·Infection and Immunity

Abstract

Enteroaggregative Escherichia coli (EAEC) is increasingly being recognized as a cause of diarrheal disease in diverse populations. No small animal model is currently available to study this pathogen. We report here that conventional mice orally inoculated with prototype EAEC strain 042 generally became colonized, though the abundance of organisms cultured from their stool varied substantially among individual animals. In contrast, mice whose water contained 5 g/liter streptomycin consistently became colonized at high levels (ca. 10 8 CFU/g of stool). Neither conventional nor streptomycin-treated mice developed clinical signs or histopathologic abnormalities. Using specific mutants in competition with the wild-type strain, we evaluated the contribution of several putative EAEC virulence factors to colonization of streptomycin-treated mice. Our data suggest that the dispersin surface protein and Pic, a serine protease autotransporter secreted by EAEC and Shigella flexneri , promote colonization of the mouse. In contrast, we found no role for the aggregative adherence fimbriae, the transcriptional activator AggR, or the surface factor termed Air (entero a ggregative i mmunoglobulin r epeat protein). To study Pic further, we constructed a single nucleotide mutation in strain 042 which altered only the Pic catalytic serine (strain 042PicS258A). Fractionation of the tissue at 24 h and 3 days demonstrated an approximate 3-log 10 difference between 042 and 042PicS258A in the lumen and mucus layer and adherent to tissue. Strains 042 and 042PicS258A adhered similarly to mouse tissue ex vivo. While no growth differences were observed in a continuous-flow anaerobic intestinal simulator system, the wild-type strain exhibited a growth advantage over 042PicS258A in a culture of cecal mucus and in cecal contents in vitro; this difference was manifest only after 6 h of growth. Moreover, enhanced growth of the wild type was observed in comparison with that of the mutant in minimal medium containing mucin but not in the absence of mucin. The data suggest a novel metabolic role for the Pic mucinase in EAEC colonization.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1128/iai.01494-08

Cites

47 of 47 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The serine protease Pic produced by E. coli (EAEC), Citrobacter and Shigella flexneri is a virulence factor associated with adherence, colonization and evasion of the innate immune system.

    “the serine protease Pic produced by E. coli (EAEC), Citrobacter and Shigella flexneri is a virulence factor associated with adherence, colonization and evasion of the innate immune system.68–71”
  • Proteases from infectious agents such as Pic in diarrheagenic E. coli and Shigella, or vibriolysin in V. cholera, degrade colonic mucus, which is a key step facilitating epithelium invasion.

    “Proteases from different infectious agents such as Pic in diarrheagenic E. coli and Shigella, or vibriolysin in V. cholera, degrade the colonic mucus, which is a key step facilitating epithelium invasion.10,68,69,71”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Harrington, S. M., Sheikh, J., Henderson, I. R., Ruiz-Perez, F., Cohen, P. S., & Nataro, J. P.
Affiliations
  • Center for Vaccine Development, University of Maryland School of Medicine, and Departments of Microbiology and Immunology
  • University of Maryland, Baltimore (US)
  • University of Rhode Island (US)
  • Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland 21201
Venue
Infection and Immunity
Published
2009-06
Volume
77
Issue
6
Pages
2465-2473
ISSN
  • 0019-9567 (ISSN-L)
  • 1098-5522
OpenAlex
W2161414686
Cited by
156
References
47
Citations by year
2026: 5 · 2025: 10 · 2024: 6 · 2023: 6 · 2022: 5 · 2021: 6 · 2020: 13 · 2019: 6 · 2018: 12 · 2017: 10 · 2016: 6 · 2015: 10 · 2014: 11 · 2013: 16 · 2012: 11
FWCI
7.17
Type
journal article
Language
en
Open access
Locations
  • Infection and Immunity (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Journal of Media Literacy Education (submittedVersion, cc-by)
  • University of Birmingham Research Portal (University of Birmingham) (submittedVersion)
Funders
National Institute of Allergy and Infectious Diseases (R56AI048945, R01AI033096, R01AI043615, R01AI048945, AI33096, AI43615, AI48945, AI03615, R56AI043615)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Endocrinology › Escherichia coli research studies
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Endocrinology › Enterobacteriaceae and Cronobacter Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
Keywords
enteroaggregative Escherichia coli, mucinase, intestinal colonization, mucin, aggregative adherence fimbriae, aggR, virulence factors, diarrheal disease
MeSH terms
Animals, Cecum, Child, Escherichia coli, Feces, Female, Humans, Intestinal Mucosa, Mice, Inbred BALB C, Mucins, Polysaccharide-Lyases, Serine Endopeptidases, Shigella flexneri, Virulence, Colony Count, Microbial, Mutagenesis, Site-Directed, Gene Deletion, Amino Acid Substitution, Catalytic Domain, Escherichia coli Proteins, Virulence Factors, Mice

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review