Related Experiment Video
Updated: May 30, 2026
09:25
Implementation 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
Staphylococcus sciuri exfoliative toxin C (ExhC) is a necrosis-inducer for mammalian cells
Haihua Li1, Yongqiang Wang, Lin Ding
1State Key Laboratory of Agrobiotechnology, and Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China.
Plos One
|August 11, 2011
Summary
Staphylococcus sciuri toxin ExhC causes cell necrosis and skin lesions in mice. A specific amino acid region (79-128) is crucial for this necrosis-inducing activity.
Area of Science:
- Microbiology
- Pathogen Research
- Toxinology
Background:
- Staphylococcus sciuri is an uncommon human pathogen.
- A recent S. sciuri isolate caused fatal exudative epidermitis in piglets, suggesting zoonotic potential.
- Understanding S. sciuri pathogenicity is crucial due to its potential as a zoonotic agent.
Purpose of the Study:
- To investigate the pathogenicity of Staphylococcus sciuri.
- To analyze the function of exfoliative toxin C (ExhC) from S. sciuri.
- To identify the necrosis-inducing domain of the ExhC toxin.
Main Methods:
- Cloning and functional analysis of recombinant ExhC-his (rExhC).
- In vitro cell culture assays using multiple cell lines and peritoneal macrophages.
- In vivo studies using newborn mice to assess pathogenicity and skin lesions.
Main Results:
- Recombinant ExhC (rExhC) induced necrosis in cell lines and macrophages.
- rExhC caused skin lesions in newborn mice.
- Deletion or antibody blockade of amino acids 79-128 abolished rExhC's necrosis-inducing effects, identifying this as a key domain.
Conclusions:
- The ExhC toxin from Staphylococcus sciuri possesses necrosis-inducing properties.
- Amino acids 79-128 of ExhC are essential for its cytotoxic and pathogenic effects.
- This study enhances understanding of Staphylococcus sciuri infection mechanisms.
Related Concept Videos
01:29Staphylococcal Skin Infections
Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
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...
01:19Clinical Applications of Epidermal Stem Cells
Epidermal stem cells (EpiSCs) are mainly located at the basal layer of the epidermis. These cells repair minor injuries of the skin and replace dead skin cells. However, EpiSCs’ cannot heal severe wounds such as major burns or those from diabetes or hereditary disorders. In such cases, culturing the epidermal stem cells from the patient is possible and has yielded successful treatment options, such as laboratory-grown skin grafts. These grafts are synthesized using a patient’s own EpiSCs...
01:21Cytotoxic Edema: Pathophysiology
Cytotoxic edema is a form of cerebral edema characterized by intracellular swelling of neurons, astrocytes, and other glial cells. It develops when the mechanisms responsible for maintaining ionic gradients across the cell membrane become impaired. Under normal physiological conditions, the sodium–potassium ATPase actively transports sodium ions out of the cell and potassium ions into the cell, preserving osmotic balance and enabling electrical signaling. This pump requires a continuous supply...