Previous results have implicated an important role for the enzyme IIScr, the @entity969 -specific permease, in the transport of @entity969 by cariogenic @entity6586 . The product of the scrB gene, @entity69723 hydrolase (Suc-6PH), is required for the metabolism of phosphorylated @entity969 . The results from the utilization of scrB::lacZ fusions in @entity6586 GS-5 have suggested that @entity969 -grown cells have higher levels of scrB gene expression than do cells grown with @entity413 or @entity948 . Northern blot analysis of scrB transcripts has also confirmed the relative strengths of expression as @entity969 > @entity413 > @entity948 . Immediately downstream from the scrB gene, an open reading frame with homology to regulatory proteins of the GalR-LacI family as well as to ScrR proteins from several other bacteria has been identified. In addition, this gene appears to be transcribed in the same operon as scrB. Inactivation of this gene, scrR, did not alter the relative expression of the scrB gene in the presence of @entity969 or @entity948 but did increase SUC-6PH levels in the presence of @entity413 to that observed with @entity969 . Furthermore, the @entity6586 ScrR homolog appears to bind to the scrB promoter region as determined from the results of gel shift assays. These results suggest that the scrR gene is involved in the regulation of scrB, and likely scrA, expression. However, it is not clear whether @entity969 acts as an inducer of expression of these genes or, alternatively, whether @entity413 and @entity948 act as repressors.

Regulation of @entity69723 hydrolase activity in XXXX : characterization of the scrR gene.

@entity6586 :: ('1309', 'Species') :: ['Streptococcus mutans', 'S. mutans'] @entity948 :: ('MESH:D005632', 'Chemical') :: ['fructose'] @entity969 :: ('MESH:D013395', 'Chemical') :: ['sucrose'] @entity69723 :: ('MESH:C535046', 'Chemical') :: ['sucrose-6-phosphate'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose']
@entity6586 :: (1309,Species) :: ['Streptococcus mutans']
