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Published on: August 4, 2023
Stress responses in the opportunistic pathogen Acinetobacter baumannii
Steven E Fiester1, Luis A Actis
1Department of Microbiology, Miami University, Oxford, OH 45056, USA.
Future Microbiology
|March 8, 2013
Summary
Acinetobacter baumannii infections are severe due to its ability to sense and react to stress signals. This pathogen resists nutrient deprivation, oxidative stress, and even ethanol, aiding its persistence and virulence.
Area of Science:
- Microbiology
- Infectious Diseases
- Bacterial Pathogenesis
Background:
- Acinetobacter baumannii is a significant cause of severe infections globally, particularly in vulnerable patients.
- Its persistence and dissemination in healthcare settings are linked to its ability to respond to environmental and host-derived stress signals.
Purpose of the Study:
- To review current knowledge on how environmental and cellular stressors influence Acinetobacter baumannii.
- To explore the pathogen's resistance mechanisms against nutrient deprivation, oxidative/nitrosative stress, and antiseptics like ethanol.
Main Methods:
- Literature review of experimental evidence on Acinetobacter baumannii stress responses.
- Analysis of pathogen's sensing and reaction mechanisms to various environmental cues.
Main Results:
- Acinetobacter baumannii senses and reacts to diverse stressors, including nutrient deprivation and oxidative/nitrosative injury.
- Ethanol, an antiseptic, can be perceived as a nutrient and virulence-enhancing signal by the pathogen.
- These stress responses contribute to A. baumannii pathogenesis, antibiotic resistance, and evasion of host defenses.
Conclusions:
- Understanding Acinetobacter baumannii's stress response mechanisms is crucial for combating its infections.
- Targeting these adaptive capabilities may offer novel therapeutic strategies against this opportunistic pathogen.
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