Essential Roles of the sppRA Fructose-Phosphate Phosphohydrolase Operon in Carbohydrate Metabolism and Virulence Expression by Streptococcus mutans.

ABSTRACT: The dental caries pathogen Streptococcus mutans can ferment a variety of sugars to produce organic acids. Exposure of S. mutans to certain nonmetabolizable carbohydrates, such as xylitol, impairs growth and can cause cell death. Recently, the presence of a sugar-phosphate stress in S. mutans was demonstrated using a mutant lacking 1-phosphofructokinase (FruK) that accumulates fructose-1-phosphate (F-1-P). Here, we studied an operon in S. mutans, sppRA, which was highly expressed in the fruK mutant. Biochemical characterization of a recombinant SppA protein indicated that it possessed hexose-phosphate phosphohydrolase activity, with preferences for F-1-P and, to a lesser degree, fructose-6-phosphate (F-6-P). SppA activity was stimulated by Mg²⁺

SUBMITTER: Zeng L 

PROVIDER: S-EPMC6304665 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature