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Bacteroides: the good, the bad, and the nitty-gritty
1Wadsworth Anaerobe Laboratory, Greater Los Angeles VA Healthcare Systems University of California, Los Angeles, CA 90073, USA. hwexler@ucla.edu
Clinical Microbiology Reviews
|October 16, 2007
Summary
Bacteroides species are dangerous pathogens causing infections and high mortality. Understanding their gut adaptation and increasing antibiotic resistance is crucial for clinical management.
Area of Science:
- Microbiology
- Clinical Pathogen Analysis
- Genomics and Proteomics
Background:
- Bacteroides species are key members of the human gut microbiota.
- When displaced, they become significant clinical pathogens causing infections and mortality exceeding 19%.
- Genomic and proteomic studies illuminate their adaptation strategies within the gut environment.
Purpose of the Study:
- To explore the adaptive mechanisms of Bacteroides species in the human gut.
- To understand the virulence factors contributing to pathogenicity.
- To highlight the increasing antibiotic resistance in these anaerobic pathogens.
Main Methods:
- Genomic analysis
- Proteomic analysis
- Clinical data review on infection and antibiotic resistance patterns.
Main Results:
- Bacteroides species possess sophisticated systems for nutrient sensing, toxin expulsion, and immune modulation.
- Bacteroides fragilis is a prevalent anaerobic pathogen due to potent virulence factors.
- Significant and increasing resistance to multiple antibiotics (e.g., cefoxitin, carbapenems, fluoroquinolones) is observed.
Conclusions:
- Bacteroides species are adaptable gut commensals that cause severe infections upon translocation.
- Their complex adaptive mechanisms and potent virulence factors contribute to their pathogenicity.
- Rising antibiotic resistance in Bacteroides species poses a major clinical challenge.
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