Regulation of hexitol catabolism in Streptococcus mutans.
Regulation of hexitol catabolism was investigated in Streptococcus mutans, a cariogenic human dental plaque bacterium. Induction of hexitol catabolic enzymes and phosphoenolpyruvate:hexitol phosphotransferase and hexitol phosphate dehydrogenase activities was regulated by an inducer exclusion mechanism initiated by D-glucose and 2-deoxy-D-glucose. Kinetic analysis of the inhibitory effect of 2-deoxy-D-glucose on initial hexitol uptake illustrated that this was a noncompetitive type of inhibition. In mutant strains of S. mutans lacking phosphoenolpyruvate:glucose phosphotransferase activity, 2-deoxy-D-glucose was unable to inhibit hexitol uptake. These observations provide evidence for possible molecular mechanisms for the exclusion process.
D001692:Biological Transport / Q000187:drug effects; D003837:Deoxy Sugars / Q000494:pharmacology*; D003847:Deoxyglucose / Q000494:pharmacology*; D004790:Enzyme Induction; D029968:Escherichia coli Proteins; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology*; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D008353:Mannitol / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000096:biosynthesis; D013012:Sorbitol / Q000378:metabolism*; D013295:Streptococcus mutans / Q000378:metabolism*; D013401:Sugar Alcohol Dehydrogenases / Q000096:biosynthesis
D003837:Deoxy Sugars; D029968:Escherichia coli Proteins; D007773:Lactates; D009004:Monosaccharide Transport Proteins; D019344:Lactic Acid; D008353:Mannitol; D013012:Sorbitol; D003847:Deoxyglucose; D013401:Sugar Alcohol Dehydrogenases; C022645:sorbitol-6-phosphate dehydrogenase; C021544:mannitol-1-phosphate dehydrogenase; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C022358:mannitol PTS permease, E coli; C034466:phosphoenolpyruvate-sorbitol phosphotransferase; D005947:Glucose