Related Experiment Videos
A binding protein-dependent transport system in Streptococcus mutans responsible for multiple sugar metabolism
R R Russell1, J Aduse-Opoku, I C Sutcliffe
1Department of Oral Biology, University of Newcastle upon Tyne, United Kingdom.
The Journal of Biological Chemistry
|March 5, 1992
Summary
Streptococcus mutans possesses an 11-kilobase gene region, the msm system, for multiple sugar uptake and metabolism. This system involves eight genes, including those for alpha-galactosidase and sucrose phosphorylase, enabling the transport of melibiose and raffinose.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Streptococcus mutans is a key bacterium in dental caries.
- Understanding its metabolic pathways is crucial for developing targeted interventions.
- The genetic basis for multi-sugar metabolism in S. mutans was previously not fully elucidated.
Purpose of the Study:
- To identify and characterize the genetic region responsible for the uptake and metabolism of multiple sugars in Streptococcus mutans.
- To elucidate the specific genes and proteins involved in this multi-sugar transport system.
- To understand the regulatory mechanisms governing this operon.
Main Methods:
- Gene sequencing and analysis of an 11-kilobase region in Streptococcus mutans.
- Identification of eight contiguous genes comprising the msm system.
- Insertional inactivation of genes and subsequent uptake data analysis.
- Bioinformatic analysis to determine protein homology.
Main Results:
- An 11-kilobase operon, termed the msm system, was identified in Streptococcus mutans.
- Eight contiguous genes were characterized, specifying proteins homologous to periplasmic binding protein-dependent transport systems.
- The msm system facilitates the uptake of melibiose, raffinose, and isomaltotriose, and metabolism of melibiose, sucrose, and isomaltosaccharides.
- A positive regulatory gene, msmR, was identified.
Conclusions:
- The msm system in Streptococcus mutans is a complex genetic locus responsible for the transport and metabolism of specific multi-sugar compounds.
- The identified proteins show homology to known transport systems, suggesting conserved mechanisms.
- This research provides a detailed molecular understanding of sugar metabolism in S. mutans.