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Regulation of Cysteine Homeostasis and Its Effect on Escherichia coli Sensitivity to Ciprofloxacin in LB Medium.
- Source :
- International Journal of Molecular Sciences; Apr2024, Vol. 25 Issue 8, p4424, 21p
- Publication Year :
- 2024
-
Abstract
- Cysteine and its derivatives, including H<subscript>2</subscript>S, can influence bacterial virulence and sensitivity to antibiotics. In minimal sulfate media, H<subscript>2</subscript>S is generated under stress to prevent excess cysteine and, together with incorporation into glutathione and export into the medium, is a mechanism of cysteine homeostasis. Here, we studied the features of cysteine homeostasis in LB medium, where the main source of sulfur is cystine, whose import can create excess cysteine inside cells. We used mutants in the mechanisms of cysteine homeostasis and a set of microbiological and biochemical methods, including the real-time monitoring of sulfide and oxygen, the determination of cysteine and glutathione (GSH), and the expression of the Fur, OxyR, and SOS regulons genes. During normal growth, the parental strain generated H<subscript>2</subscript>S when switching respiration to another substrate. The mutations affected the onset time, the intensity and duration of H<subscript>2</subscript>S production, cysteine and glutathione levels, bacterial growth and respiration rates, and the induction of defense systems. Exposure to chloramphenicol and high doses of ciprofloxacin increased cysteine content and GSH synthesis. A high inverse relationship between log CFU/mL and bacterial growth rate before ciprofloxacin addition was revealed. The study points to the important role of maintaining cysteine homeostasis during normal growth and antibiotic exposure in LB medium. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 16616596
- Volume :
- 25
- Issue :
- 8
- Database :
- Complementary Index
- Journal :
- International Journal of Molecular Sciences
- Publication Type :
- Academic Journal
- Accession number :
- 176879432
- Full Text :
- https://doi.org/10.3390/ijms25084424