Characterization of Pic, a Secreted Protease of Shigella flexneri and Enteroaggregative Escherichia coli
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We have identified and characterized a secreted protein, designated Pic, which is encoded on the chromosomes of enteroaggregative Escherichia coli (EAEC) 042 and Shigella flexneri 2457T. The product of the pic gene is synthesized as a 146.5-kDa precursor molecule which is processed at the N and C termini during secretion, allowing the release of a mature protein (109.8 kDa) into the culture supernatant. The deduced amino acid sequence of Pic shows high homology to autotransporter proteins, particularly a subgroup termed the SPATEs (serine protease autotransporters of the Enterobacteriaceae ). Present in all members of this subgroup is a motif similar to the active sites of certain serine proteases. Pic catalyzes gelatin degradation, which can be abolished by disruption of the predicted proteolytic active site. Functional analysis of the Pic protein implicates this factor in mucinase activity, serum resistance, and hemagglutination. Our data suggest that Pic may be a multifunctional protein involved in enteric pathogenesis.
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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”
From The emerging roles of bacterial proteases in intestinal diseases (2023) · cites this paper as [68]
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”
From The emerging roles of bacterial proteases in intestinal diseases (2023) · cites this paper as [68]
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References 86 · Cited by 357
Research works printed but not linked: 2
- [3]Ausubel F M, Brent R, Kingston R E, Moore D D, Seidman J G, Smith J A, Struhl K, editors. Current protocols in molecular biology. New York, N.Y: Greene Publishing Associates; 1989. [Google Scholar]
- [24]Eslava C, Villaseca J, Morales R, Navarro A, Cravioto A. Abstracts of the 93rd General Meeting of the American Society for Microbiology 1993. Washington, D.C: American Society for Microbiology; 1993. Identification of a protein with toxigenic activity produced by enteroaggregative Escherichia coli, abstr. B105; p. 44. [Google Scholar]
- Authors
- Henderson, I. R., Czeczulin, J., Eslava, C., Noriega, F., & Nataro, J. P.
- Affiliations
- University of Maryland, Baltimore (US)
- Universidad Nacional Autónoma de México (MX)
- Venue
- Infection and Immunity
- Publisher
- American Society for Microbiology
- Published
- 1999-11
- Volume
- 67
- Issue
- 11
- Pages
- 5587-5596
- ISSN
- 0019-9567 (ISSN-L)
- 1098-5522
- PMC
- PMC96930
- OpenAlex
- W2155208387
- Cited by
- 357
- References
- 86
- Citations by year
- 2026: 8 · 2025: 2 · 2024: 7 · 2023: 12 · 2022: 15 · 2021: 10 · 2020: 21 · 2019: 9 · 2018: 7 · 2017: 21 · 2016: 18 · 2015: 14 · 2014: 16 · 2013: 21 · 2012: 21
- FWCI
- 6.83
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Infection and Immunity (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institute of Allergy and Infectious Diseases (R01AI033096, AI33096)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Endocrinology › Escherichia coli research studies
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Bacterial Genetics and Biotechnology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Biochemical and Structural Characterization
- Keywords
- extracellular protease, Shigella flexneri, enteroaggregative Escherichia coli, SPATE, autotransporter proteins, gelatin degradation, serum resistance, hemagglutination, protein secretion
- MeSH terms
- Adult, Animals, Bacterial Proteins, Blood Bactericidal Activity, Cloning, Molecular, Escherichia coli, Hemagglutination, Humans, Molecular Sequence Data, Endopeptidases, Rabbits, Shigella flexneri, Mice, Serine Proteases
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