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Published on: May 23, 2021
Escherichia coli Subtilase Cytotoxin.
Adrienne W Paton1, James C Paton
1Research Centre for Infectious Diseases, School of Molecular and Biomedical Science, University of Adelaide, Adelaide, SA 5005, Australia.
Toxins
|September 28, 2010
Summary
Shiga toxin-producing E. coli produces Subtilase cytotoxin (SubAB), which cleaves BiP/GRP78 in the endoplasmic reticulum. This triggers cell stress and apoptosis, offering insights into cellular functions and disease pathogenesis.
Area of Science:
- Microbiology
- Cell Biology
- Toxicology
Background:
- Subtilase cytotoxin (SubAB) is a novel AB(5) toxin from Shiga toxigenic Escherichia coli (STEC).
- SubAB targets BiP/GRP78, an essential endoplasmic reticulum (ER) chaperone, via protease cleavage.
- The B subunit binds to N-glycolylneuraminic acid-terminated glycans.
Purpose of the Study:
- To elucidate the mechanism of SubAB-induced cytotoxicity.
- To investigate the role of BiP/GRP78 cleavage in ER stress and apoptosis.
- To explore SubAB as a tool for studying ER stress responses.
Main Methods:
- Biochemical assays to characterize SubAB activity.
- Cell-based assays to assess cytotoxicity and ER stress markers.
- In vivo studies in mouse models.
Main Results:
- SubAB's A subunit cleaves BiP/GRP78 at a specific site within the ER.
- This cleavage induces a potent and unresolved ER stress response.
- The cellular response culminates in apoptosis.
- SubAB is lethal in mice and causes pathology resembling hemolytic uremic syndrome.
Conclusions:
- SubAB-induced BiP/GRP78 cleavage is a key mechanism of cytotoxicity.
- SubAB triggers significant ER stress, leading to programmed cell death.
- SubAB serves as a valuable research tool for understanding ER stress and BiP function.
- SubAB's pathogenic potential in human disease warrants further investigation.
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