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Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092
Published on: October 2, 2017
Xylitol and capsular gene expression in Streptococcus pneumoniae
Paula Kurola1, Terhi Tapiainen2, Tarja Kaijalainen1
1National Institute for Health and Welfare, Oulu, Finland.
Journal of Medical Microbiology
|July 11, 2009
Summary
Xylitol, a sugar alcohol, significantly reduces Streptococcus pneumoniae cpsB gene expression. This finding supports xylitol
Area of Science:
- Microbiology
- Molecular Biology
- Pharmacology
Background:
- Xylitol, a sugar alcohol, inhibits Streptococcus pneumoniae growth and adherence.
- Clinical studies show xylitol reduces acute otitis media in children but not nasopharyngeal carriage.
- Xylitol affects pneumococcal capsule ultrastructure, suggesting effects on gene expression.
Purpose of the Study:
- To investigate the hypothesis that xylitol affects the expression of pneumococcal capsular genes.
- To determine if xylitol influences the mRNA levels of the cpsB gene in Streptococcus pneumoniae.
Main Methods:
- Studied 24 clinical isolates and one ATCC strain of Streptococcus pneumoniae.
- Exposed bacteria to glucose, xylitol, or control medium for 2 hours.
- Quantified cpsB gene expression using real-time RT-PCR and relative quantification with 16S rRNA as reference.
Main Results:
- Xylitol exposure significantly lowered cpsB gene expression compared to control (P=0.035) and glucose (P=0.011) media.
- Demonstrated a statistically significant reduction in capsule gene expression upon xylitol treatment.
Conclusions:
- Xylitol significantly downregulates the expression of the Streptococcus pneumoniae cpsB gene.
- This downregulation supports previous findings on xylitol's effect on pneumococcal capsule ultrastructure.
- The findings may explain xylitol's clinical efficacy in preventing otitis media.
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