GSE110275 Characterization of the trehalose utilization operon in Streptococcus mutans reveals that the TreR transcriptional regulator is involved in stress response pathways and toxin production

In this study, deletion mutants of all three genes in the putative S. mutans trehalose utilization operon were characterized and shown to be required for wild-type levels of growth when trehalose was the only carbohydrate source provided. Interestingly, the TreR transcriptional regulator appeared to be critical for responding to oxidative stress, and for mounting a protective stress tolerance response following growth at moderately acidic pH. RNAseq of a treR deletion mutant suggested that in S. mutans, TreR acts as a trehalose-sensing activator of transcription of the tre operon, rather than a repressor, as described in other species. In addition, deletion of treR caused the down-regulation of a number of genes involved in genetic competence and bacteriocin production, supporting results of a recent study linking trehalose and the S. mutans competence pathways. Finally, deletion of treR compromised the ability of S. mutans to inhibit the growth of the competing species, Streptococcus gordonii and Lactococcus lactis. Taken together, this study solidifies the role of the S. mutans tre operon in trehalose utilization and suggests novel functions for the TreR regulator, including roles in stress response and competitive fitness.
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Expression profiling by high throughput sequencing Streptococcus mutans Source Type: research