Sage Journals: Discover world-class research

Abstract

Xylitol is transported by Streptococcus mutans via a constitutive phosphoenolpyruvate:fructose phosphotransferase system (PTS) composed of a IIABC protein. Spontaneous xylitol-resistant strains are depleted in constitutive fructose-PTS activity, exhibit additional phenotypes, and are associated with the caries-preventive properties of xylitol. Polymerase chain-reactions and chromosome walking were used to clone the fxp operon that codes for the constitutive fructose/xylitol-PTS. The operon contained three open reading frames: fxpA, which coded for a putative regulatory protein of the deoxyribose repressor (DeoR) family, fxpB, which coded for a 1-phosphofructokinase, and fxpC, which coded for a IIABC protein of the fructose-PTS family. Northern blot analysis revealed that these genes were co-transcribed into a 4.4-kb mRNA even in the absence of fructose. Inactivation of the fxpC gene conferred resistance to xylitol, confirming its function. The fxp operon is also present in the genomes of other xylitol-sensitive streptococci, which could explain their sensitivity to xylitol.

Get full access to this article

View all access options for this article.

References

Ausubel FM, Brent R, Kingston RE, Moore DD, Seidman JG, Smith JA, et al., editors -1990-. Current protocols in molecular biology. New York: Greene Publishing Associates and Wiley Interscience.

Belouski E, Watson DE, Bennett GN -1998-. Cloning, sequence, and expression of the phosphofructokinase gene of Clostridium acetobutylicum ATCC824 in Escherichia coli. Curr Microbiol 37:17–22.

Buckley ND, Lee LN, LeBlanc DJ -1995-. Use of a novel mobilizable vector to inactivate the ScrA gene of Streptococcus sobrinus by allelic replacement. J Bacteriol 177:5028–5034.

Buckley ND, Vadeboncoeur C, LeBlanc DJ, Lee LN, Frenette M -1999-. An effective strategy applicable to Streptococcus salivarius and related bacteria, to enhance or confer electrocompetence. Appl Environ Microbiol 65:3800–3804.

de Crécy-Lagard V, Bouvet OMM, Lejeune P, Danchin A -1991-. Fructose catabolism in Xanthomonas campestris pv Campestris. J Biol Chem 266:18154–18161.

Devereux J, Haeberli P, Smithies O -1984-. A comprehensive set of sequence analysis programs for the VAX. Nucleic Acids Res 12:387–395.

Gauthier L, Vadeboncoeur C, Mayrand D -1984-. Isolation of a novel protein involved in the transport of fructose by an inducible phosphoenolpyruvate fructose phosphotransferase system in Streptococcus mutans. J Bacteriol 160:755–763.

Hueck CJ, Hillen W -1995-. Catabolite repression in Bacillus subtilis: a global regulatory mechanism for the Gram-positive bacteria? Mol Microbiol 15:395–401.

Kontiokari T, Uhari M, Koskela M -1995-. Effect of xylitol on growth of nasopharyngeal bacteria in vitro. Antimicrob Agents Chemother 39:1820–1823.

10.

Lemay M -1996-. Caractérisation des gènes fruK et fruL codant respectivement pour la 1-phosphofructokinase et l’enzyme IIBC^Fru de l’opéron PTS fructose chez Streptococcus mutans 123.1 -MSc thesis-. Québec, QC: Université Laval.

11.

Lengeler JW, Jahreis K, Wehmeier UF -1994-. Enzymes II of the phosphoenolpyruvate-dependent phosphotransferase systems: their structure and function in carbohydrate transport. Biochim Biophys Acta 1188:1–28.

12.

Loesche WJ -1985-. The rationale for caries prevention through the use of sugar substitutes. Int Dent J 35:1–8.

13.

Lortie L-A, Gagnon G, Frenette M -1994-. IS1139 from Streptococcus salivarius: identification and characterization of an insertion sequence-like element related to mobile DNA elements from Gram-negative bacteria. Plasmid 32:1–9.

14.

Mortensen L, Dandanell G, Hammer K -1989-. Purification and characterization of the deoR repressor of Escherichia coli. EMBO J 8:325–331.

15.

Pon CL, Brombach M, Thamm S, Gualerzi CO -1989-. Cloning and characterization of a gene cluster from Bacillus stearothermophilus comprising infC, rpmI and rplT. Mol Gen Genet 18:355–357.

16.

Postma PW, Lengeler JW, Jacobson GR -1993-. Phosphoenolpyruvate: carbohydrate phosphotransferase systems of bacteria. Microbiol Rev 57:543–594.

17.

Reizer J, Reizer A, Kornberg HL, Saier MH Jr -1994-. Sequence of the fruB gene of Escherichia coli encoding the diphosphoryl transfer protein -DTP- of the phosphoenolpyruvate: sugar phosphotransferase system. FEMS Microbiol Lett 118:159–162.

18.

Reizer J, Reizer A, Saier MH Jr -1995-. Novel phosphotransferase system genes revealed by bacterial genome analysis—a gene cluster encoding a unique enzyme I and the proteins of a fructose-like permease system. Microbiology 141:961–971.

19.

Rosey EL, Stewart GC -1992-. Nucleotide and deduced amino acid sequences of the lacR, lacABCD, and lacFE genes encoding the repressor, tagatose 6-phosphate gene cluster, and sugar-specific phosphotransferase system components of the lactose operon of Streptococcus mutans. J Bacteriol 174:6159–6170.

20.

Schweizer HP, Po C -1996-. Regulation of glycerol metabolism in Pseudomonas aeruginosa: characterization of the glpR repressor gene. J Bacteriol 178:5215–5221.

21.

Tanzer JM -1995-. Xylitol chewing gum and dental caries. Int Dent J 45-1 Suppl-:65–76.

22.

Trahan L -1995-. Xylitol: a review of its action on mutans streptococci and dental plaque—its clinical significance. Int Dent J 45:77–92.

23.

Trahan L, Bareil M, Gauthier L, Vadeboncoeur C -1985-. Transport and phosphorylation of xylitol by a fructose phosphotransferase system in Streptococcus mutans. Caries Res 19:53–63.

24.

Trahan L, Bourgeau G, Breton R -1996-. Emergence of xylitol-resistant -Frucose PTS^-- mutants from human isolates of mutans streptococci during growth on dietary sugars in the presence of xylitol. J Dent Res 75:1892–1996.

25.

Uhari M, Kontiokari T, Koskela M, Niemela M -1996-. Xylitol chewing gum in prevention of acute otitis media: double blind randomised trial. BMJ 313:1180–4.

26.

Vadeboncoeur C, Trahan L -1983-. Comparative study of Streptococcus mutans laboratory srains and fresh isolates from carious and caries-free tooth surfaces from subjects with hereditary fructose intolerance. Infect Immun 40:81–90.

27.

van Houte J -1994-. Role of micro-organisms in caries etiology. J Dent Res 73:672–681.

28.

Weickert MJ, Chambliss GH -1990-. Site-directed mutagenesis of a catabolite repression operator sequence in Bacillus subtilis. Proc Natl Acad Sci USA 87:6238–6242.

29.

Wen ZT, Browngardt C, Burne RA -2001-. Characterization of two operons that encode components of fructose-specific enzyme II of the sugar:phosphotransferase system of Streptococcus mutans. FEMS Microbiol Lett 205:337–342.

30.

Ye JJ, Saier MH Jr -1996-. Regulation of sugar uptake via the phosphoenolpyruvate-dependent phosphotransferase systems in Bacillus subtilis and Lactococcus lactis is mediated by ATP-dependent phosphorylation of seryl residue 46 in HPr. J Bacteriol 178:3557–3563.

Inactivation of the Streptococcus mutans fxpC Gene Confers Resistance to Xylitol,a Caries-preventive Natural Carbohydrate Sweetener

Abstract

Get full access to this article

References