Raman spectroscopy of xylitol uptake and metabolism in Gram-positive and Gram-negative bacteria.

Abstract

Visible-wavelength Raman spectroscopy was used to investigate the uptake and metabolism of the five-carbon sugar alcohol xylitol by Gram-positive viridans group streptococcus and the two extensively used strains of Gram-negative Escherichia coli, E. coli C and E. coli K-12. E. coli C, but not E. coli K-12, contains a complete xylitol operon, and the viridans group streptococcus contains an incomplete xylitol operon used to metabolize the xylitol. Raman spectra from xylitol-exposed viridans group streptococcus exhibited significant changes that persisted even in progeny grown from the xylitol-exposed mother cells in a xylitol-free medium for 24 h. This behavior was not observed in the E. coli K-12. In both viridans group streptococcus and the E. coli C derivative HF4714, the metabolic intermediates are stably formed to create an anomaly in bacterial normal survival. The uptake of xylitol by Gram-positive and Gram-negative pathogens occurs even in the presence of other high-calorie sugars, and its stable integration within the bacterial cell wall may discontinue bacterial multiplication. This could be a contributing factor for the known efficacy of xylitol when taken as a prophylactic measure to prevent or reduce occurrences of persistent infection. Specifically, these bacteria are causative agents for several important diseases of children such as pneumonia, otitis media, meningitis, and dental caries. If properly explored, such an inexpensive and harmless sugar-alcohol, alone or used in conjunction with fluoride, would pave the way to an alternative preventive therapy for these childhood diseases when the causative pathogens have become resistant to modern medicines such as antibiotics and vaccine immunotherapy.

• Authors: Sunil Palchaudhuri, Steven J Rehse, Khozima Hamasha, Talha Syed, Eldar Kurtovic, Emir Kurtovic, James Stenger
• Journal: Applied and environmental microbiology (Appl Environ Microbiol) Vol. 77 Issue 1 Pg. 131-7 (Jan 2011) ISSN: 1098-5336 [Electronic] United States
• PMID: 21037297 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Xylitol

Topics

• Cell Wall (chemistry)
• Escherichia coli (chemistry, growth & development, metabolism)
• Genes, Bacterial
• Operon
• Spectrum Analysis, Raman (methods)
• Streptococcus (chemistry, growth & development, metabolism)
• Xylitol (metabolism)