1. Repression of the TreR transcriptional regulator in Streptococcus mutans by the global regulator, CcpA
- Author
-
E L Lindsay, Robert G. Quivey, and Roberta C. Faustoferri
- Subjects
Operon ,Regulator ,Repressor ,Microbiology ,Streptococcus mutans ,03 medical and health sciences ,chemistry.chemical_compound ,Bacterial Proteins ,Research Letter ,Genetics ,Electrophoretic mobility shift assay ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,biology ,030306 microbiology ,Catabolism ,Gene Expression Regulation, Bacterial ,biology.organism_classification ,Trehalose ,Cell biology ,DNA-Binding Proteins ,Repressor Proteins ,chemistry ,CCPA ,bacteria ,Gene Deletion - Abstract
Streptococcus mutans, the etiologic agent of dental caries in humans, is considered a dominating force in the oral microbiome due to its highly-evolved propensity for survival. The oral pathogen encodes an elaborate array of regulatory elements, including the carbon catabolite-responsive regulator, CcpA, a global regulator key in the control of sugar metabolism and in stress tolerance response mechanisms. The recently characterized trehalose utilization operon, integral for the catabolism of the disaccharide trehalose, is controlled by a local regulator, TreR, which has been implicated in a number of cellular functions outside of trehalose catabolism. Electrophoretic mobility shift assays demonstrated that CcpA bound a putative cre site in the treR promoter. Loss of ccpA resulted in elevated expression of treR in cultures of the organism grown in glucose or trehalose, indicating that CcpA not only acts as a repressor of trehalose catabolism genes, but also the local regulator. The loss of both CcpA and TreR in S. mutans resulted in an impaired growth rate and fitness response, supporting the hypothesis that these regulators are involved in carbon catabolism control and in induction of components of the organism's stress response.
- Published
- 2021
- Full Text
- View/download PDF