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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
Tissue tropisms in group A streptococcal infections
Debra E Bessen1, Sergio Lizano
1Department of Microbiology & Immunology, New York Medical College, Valhalla, NY 10573, USA. debra_bessen@nymc.edu
Future Microbiology
|April 1, 2010
Summary
Group A Streptococcus (GAS) causes mild throat and skin infections. Genetic changes, like recombinational replacement, help GAS adapt to new niches, influencing its tissue tropisms.
Area of Science:
- Microbiology
- Pathogen Biology
- Epidemiology
Background:
- Group A Streptococcus (GAS) is a globally prevalent human pathogen.
- GAS infections typically manifest as mild diseases of the throat or skin epithelium.
- Distinct GAS strains adapted to throat or skin niches have been hypothesized.
Purpose of the Study:
- To examine the epidemiology, population biology, and molecular pathogenesis of GAS tissue site preferences.
- To emphasize the laboratory's findings on GAS skin tropisms.
- To explore the genetic mechanisms underlying GAS niche adaptation.
Main Methods:
- Review of epidemiological data on GAS infections.
- Analysis of population biology studies related to GAS.
- Investigation of molecular pathogenesis mechanisms, focusing on skin tropisms.
- Examination of genetic exchange and gene form replacement in GAS.
Main Results:
- GAS exhibits distinct preferences for infecting throat or skin epithelial surfaces.
- The throat and skin are critical ecological niches for GAS reproduction and transmission.
- Recombinational replacement of orthologous genes after interspecies transfer is a key mechanism for GAS niche exploitation.
Conclusions:
- Understanding GAS tissue tropisms requires integrating epidemiology, population biology, and molecular pathogenesis.
- Genetic adaptation, particularly through recombinational replacement, is crucial for GAS to colonize new host niches.
- Further research into GAS molecular pathogenesis can elucidate strategies for controlling infections.
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