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Published on: May 13, 2019
Variable carbon catabolism among Salmonella enterica serovar Typhi isolates
Lay Ching Chai1, Boon Hong Kong, Omar Ismail Elemfareji
1Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
Plos One
|June 5, 2012
Summary
Salmonella Typhi (S. Typhi) has limited carbon metabolism, thriving on human-specific nutrients. This suggests S. Typhi persists within the human host by utilizing specific metabolic niches.
Area of Science:
- Microbiology
- Pathogen Metabolism
- Host-Pathogen Interactions
Background:
- Salmonella enterica serovar Typhi (S. Typhi) is a human-specific pathogen causing typhoid fever and chronic carriage.
- Understanding S. Typhi's unique lifestyle and pathogenesis in humans is crucial but remains largely unknown.
Purpose of the Study:
- To investigate the metabolic capabilities of S. Typhi strains.
- To elucidate the factors contributing to S. Typhi's intracellular lifestyle and persistence in human hosts.
Main Methods:
- Phenotypic microarray analysis of 190 carbon sources across diverse S. Typhi strains.
- Characterization of strains from various human and environmental sources.
Main Results:
- S. Typhi exhibited limited carbon catabolic capacity, utilizing only 27% of tested substrates.
- Strains preferentially utilized carbon sources abundant in the human body, such as alpha-glycerolphosphate, glycerol, L-serine, pyruvate, and lactate.
- S. Typhi strains were unable to utilize plant-associated carbon substrates.
Conclusions:
- S. Typhi's carbon metabolism is adapted for survival in nutrient-depleted human metabolic niches.
- These findings highlight the pathogen's host-specific adaptation and persistence strategies.
- Further research is needed to link carbon catabolism to S. Typhi pathogenesis and transmission.
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