This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by St Martin, E J Articles by Wittenberger, C L Search for Related Content PubMed PubMed Citation Articles by St Martin, E J Articles by Wittenberger, C L

Regulation and function of sucrose 6-phosphate hydrolase in Streptococcus mutans.

ABSTRACT

Sucrose catabolism by Streptococcus mutans is initiated by a phosphoenolpyruvate-dependent sucrose phosphotransferase reaction that produces sucrose 6-phosphate the latter is then cleaved by a sucrose 6-phosphate hydrolase reaction that yields glucose 6-phosphate and fructose. We have examined the regulation of the sucrose 6-phosphate hydrolase and found that it was synthesized constitutively whereas sucrose phosphotransferase activity was inducible. However, the levels of both sucrose phosphotransferase and sucrose 6-phosphate hydrolase were repressed when fructose was used as a growth substrate. The specific activity of sucrose 6-phosphate hydrolase in permeabilized cells was approximately 30 mmol/min per mg (dry weight of cells), and it had an apparent Km for sucrose 6-phosphate of 0.3 mM. analysis of a mutant that was missing sucrose 6-phosphate hydrolase activity revealed that its ability to hydrolyze sucrose was reduced.

This article has been cited by other articles:

• Hiratsuka, K., Wang, B., Sato, Y., Kuramitsu, H. (1998). Regulation of Sucrose-6-Phosphate Hydrolase Activity in Streptococcus mutans: Characterization of the scrR Gene. Infect. Immun. 66: 3736-3743 [Abstract] [Full Text]