Carbohydrate source effects on the transcriptome of Streptococcus mutans
|Year of publication
|MU Faculty or unit
|Dental caries is one of the most common chronic multifactorial disease. The plaque ecological balance is considered to be the key factor in aetiology of caries. For this balance is crucial the role of dietary carbohydrates. The primary etiologic agent of human dental is an acidophilic bacteria Streptococcus mutans. By employing deep sequencing of RNA (RNA-Seq) technology we have established the effects of various sugars on the regulation of gene expression in bacterium S. mutans growth on tryptic soy. Bacterium S. mutans was grown in a 5% CO2-aerobic atmosphere at 37°C on solid and liquid tryptic soy broth with cariogenic sugars represented by sucrose, fructose, glucose, galactose, lactose and non-cariogenic sugar xylitol. Gene expression was monitored by Illumina sequencing technology after a 12-hour growth of S. mutans on cariogenic or non-cariogenic sugars and compared to control culture grown without carbohydrates when results were considered as significant at padj lower than 0.01. Bacteria grown on xylitol, galactose or lactose showed only minor changes in gene expression when there was mainly downregulation of expression compared with control bacteria grown on tryptic soy broth. Another group of sugars was represented by fructose and glucose where genes involved in glycolysis and butanoate metabolism were strongly upregulated. In agreement with previous studies, the largest changes in gene expression were observed in bacteria grown on medium with sucrose. The obtained data helps to understand the impact of individual sugars on S. mutans metabolism involved in one of the most common chronic diseases affecting the human population.