Abstract
The galactose operon encoding a repressor and genes for the Leloir pathway for galactose metabolism (galactokinase, galactose-1-phosphate-uridyl transferase and UDP glucose-4-epimerase) was located adjacent to the multiple sugar metabolism (msm) operon on the chromosome of Streptococcus mutans Ingbritt (serotype c) and the complete nucleotide sequence of this 5-kilobase region was determined. The Leloir pathway was induced by the presence of galactose in the growth medium or following the release of intracellular galactose after uptake and cleavage of α-galactosides by the multiple sugar metabolism system. Analysis of the mechanism of galactose transport confirmed the absence of a galactose-specific phosphotransferase system and suggested the presence of an inducible galactose permease. Evidence is presented that galactose transport is independent of the proton motive force and may be ATP-dependent.
Original language | English (US) |
---|---|
Pages (from-to) | 137-144 |
Number of pages | 8 |
Journal | Gene |
Volume | 180 |
Issue number | 1-2 |
DOIs | |
State | Published - Nov 21 1996 |
Externally published | Yes |
Keywords
- Catabolism
- Galactose
- Pathogenic bacteria
- Permease
- Promoter
- Repressor
- Streptococcus mutans
- Sugar transport
ASJC Scopus subject areas
- Genetics