Related Experiment Video
Updated: May 27, 2026
10:41
Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
Published on: January 3, 2012
Shiga toxin: expression, distribution, and its role in the environment
Steven A Mauro1, Gerald B Koudelka
1Department of Biological Sciences, Mercyhurst College, Erie, PA 16546, USA. smauro@mercyhurst.edu
Toxins
|November 10, 2011
Summary
This review explores Shiga toxin production and distribution in environmental reservoirs. It details genetic mechanisms fine-tuning toxin output and microbe/protist interactions explaining toxin gene expression.
Area of Science:
- Environmental microbiology
- Molecular biology
- Ecotoxicology
Background:
- Shiga toxin-producing microbes are significant environmental contaminants.
- Understanding their reservoirs and gene regulation is crucial for risk assessment.
Purpose of the Study:
- To review recent advancements in understanding Shiga toxin production and distribution in the environment.
- To explore environmental reservoirs, genetic regulation, and ecological roles of Shiga toxin genes.
Main Methods:
- Literature review of environmental microbiology studies.
- Analysis of research on microbial genetics and gene regulation.
- Examination of studies on microbe-protist interactions.
Main Results:
- Expanded understanding of environmental reservoirs for Shiga toxin-producing microbes in terrestrial and aquatic ecosystems.
- Demonstration of modified genetic mechanisms for Shiga toxin gene regulation, fine-tuning toxin production.
- Postulation of reasons for microbial harboring and expression of Shiga toxin genes, linked to microbe/protist interactions.
Conclusions:
- Environmental Shiga toxin levels are influenced by diverse reservoirs and sophisticated genetic regulation.
- Microbe-protist interactions may provide ecological advantages for microbes expressing Shiga toxin genes.
More Related Videos
09:26Identification of Antibacterial Immunity Proteins in Escherichia coli using MALDI-TOF-TOF-MS/MS and Top-Down Proteomic Analysis
Published on: May 23, 2021
09:25Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
Published on: August 19, 2016
Related Concept Videos
01:18Bacterial Gastroenteritis
Bacterial gastroenteritis, characterized by diarrhea, abdominal cramps, and vomiting, is often caused by ingestion of contaminated food or water and is frequently associated with pathogenic Escherichia coli strains. These microbes exploit two principal mechanisms to inflict disease.Shiga toxin–producing E. coli, also referred to as STEC—notably O157:H7—release Shiga toxins that target ribosomes, blocking protein synthesis. The B subunit of the toxin binds the host glycolipid receptor...
01:12Bacterial Toxins
Bacterial toxins are sophisticated virulence factors that enable pathogenic bacteria to interact with, invade, and damage host tissues. These toxins fall broadly into two types: protein exotoxins, which are secreted into the environment and target specific host receptors, and lipopolysaccharide endotoxins, which are structural components of the bacterial outer membrane released primarily during bacterial lysis or membrane shedding. Exotoxins generally act more selectively, binding to cell...
01:28Gene Regulation in Microbial Communities: Quorum Sensing
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
01:23Stringent Response in E. coli
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
01:28Regulation of Bacterial Virulence
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
01:28Global Regulatory Systems
Global regulatory systems in bacteria enable rapid and coordinated responses to environmental changes by integrating sensory inputs with gene expression, ensuring efficient adaptation to fluctuating conditions. Key global regulatory mechanisms include regulons, two-component systems, sigma factors, and secondary messengers.Regulons and Global RegulatorsA regulon is a collection of genes and operons controlled by a common global regulator. These regulators enable bacteria to prioritize resource...