Project description:An essential two-component system WalRK is required for biofilm formation of streptococcus mutans mainly through transcriptional regulations.
Project description:In the oral biofilm, the mitis streptococci are among the first group of organisms to colonize the tooth surface. Their proliferation is thought to be an important factor required for antagonizing the growth of cariogenic species such as Streptococcus mutans. In this study, we used a 3-species mixed culture to demonstrate that another ubiquitous early colonizing species, Veillonella parvula, could greatly impact the competitive outcome of a mixed culture of S. mutans and S. gordonii. Transcriptome analysis further revealed that S. mutans responds differentially to its friend (V. parvula) and foe (S. gordonii). In the mixed culture with S. gordonii, all but one S. mutans sugar uptake and metabolic genes were down-regulated, while genes for alternative energy source utilization and H2O2 tolerance were up-regulated, resulting in a slower but persistent growth. In contrast, when cultured with V. parvula, S. mutans grew equally well or better than in monoculture and exhibited relatively few changes within its transcriptome. When V. parvula was introduced into the mixed culture of S. mutans and S. gordonii, it rescued the growth inhibition of S. mutans. In this 3-species environment, S. mutans increased the expression of genes required for the uptake and metabolism of minor sugars, while genes required for oxidative stress tolerance were down-regulated. We conclude that the major factors affecting the competition between S. mutans and S. gordonii are carbohydrate utilization and H2O2 resistance. The presence of V. parvula in the tri-species culture mitigates these two major factors and allows S. mutans to proliferate, despite the presence of S. gordonii. In this study, we used microarrays to investigate how S. mutans responds to different species. S. mutans was grown as either monospecies, dual-species cultures with S. gordonii or Veillonella, or tri-species cultures with S. gordonii and Veillonella. The transcriptional profile of the whole genome was examined with microarray.
Project description:The influence of cranberry proanthocyanidins on the transcriptomic responses of Streptococcus mutans during biofilm formation was investigated.
Project description:In the oral biofilm, the mitis streptococci are among the first group of organisms to colonize the tooth surface. Their proliferation is thought to be an important factor required for antagonizing the growth of cariogenic species such as Streptococcus mutans. In this study, we used a 3-species mixed culture to demonstrate that another ubiquitous early colonizing species, Veillonella parvula, could greatly impact the competitive outcome of a mixed culture of S. mutans and S. gordonii. Transcriptome analysis further revealed that S. mutans responds differentially to its friend (V. parvula) and foe (S. gordonii). In the mixed culture with S. gordonii, all but one S. mutans sugar uptake and metabolic genes were down-regulated, while genes for alternative energy source utilization and H2O2 tolerance were up-regulated, resulting in a slower but persistent growth. In contrast, when cultured with V. parvula, S. mutans grew equally well or better than in monoculture and exhibited relatively few changes within its transcriptome. When V. parvula was introduced into the mixed culture of S. mutans and S. gordonii, it rescued the growth inhibition of S. mutans. In this 3-species environment, S. mutans increased the expression of genes required for the uptake and metabolism of minor sugars, while genes required for oxidative stress tolerance were down-regulated. We conclude that the major factors affecting the competition between S. mutans and S. gordonii are carbohydrate utilization and H2O2 resistance. The presence of V. parvula in the tri-species culture mitigates these two major factors and allows S. mutans to proliferate, despite the presence of S. gordonii.
Project description:Transcriptional profiling to investigate the response of Streptococcus mutans biofilms to starch and sucrose at distinct stages of biofilm development.
Project description:RNA-Seq was used to compare the transcriptome of Streptococcus mutans UA159 during growth alone in monoculture, in coculture with Streptococcus gordonii DL1, Streptococcus sanguinis SK36 or Streptococcus oralis 34, and in a quadculture containing all four species. Individual cultures of commensal species Streptococcus gordonii DL1, Streptococcus sanguinis SK36 and Streptococcus oralis 34 were sequenced as well. This revealed a common transcriptome pattern in S. mutans when grown in mixed-species culture, indepenedent of the species identity that S. mutans was cultured with. Additionally, transcriptome changes in the commensal species could also be determined when undergoing competition from S. mutans. RNA-Seq was used to compare the transcriptome of Streptococcus mutans UA159 during growth alone in monoculture or in coculture with Streptococcus sobrinus NIDR 6715, Lactobacillus casei ATCC 4646 or Corynebacterium matruchotii ATCC 14266. These data were compared to previous coculture and quadculture RNA-Seq data with commensal streptococci (GSE209925). These data confirmed a common transcriptome pattern in S. mutans when grown in mixed-species culture with commensal streptococci that is not present with non-commensal streptococci, indepenedent of the species identity that S. mutans was cultured with.
Project description:In this experiment we collected small molecule data that represent excreted molecules by Streptococcus mutans growing as a biofilm. The S. mutans biofilms were established and incubated in anaerobic conditions. Samples were collected before and after a drastic pH drop due to glucose amendments. Control samples are included in this folder that represent molecules that were extracted from sterilized growth media only. These peaks should be subtracted from the biofilm samples prior to analyses.
Project description:Transcriptional profiling to investigate the response of Streptococcus mutans biofilms to starch and sucrose at distinct stages of biofilm development. RNA was extracted and purified from four replicate samples of each biofilm sample of interest and labeled with Cy3. For each replicate, labeled RNA was hybridized to slides along with Cy5-labeled reference RNA, extracted from S. mutans UA159 cells grown to mid-log.
Project description:Dental caries is closely associated with the virulence of Streptococcus mutans (S. mutans). The stress adaptation of S. mutans in the fluctuating oral environment is critical to the virulence expression of this bacterium. Here we used whole-genome microarrays to profile the dynamic transcriptomic responses of S. mutans during physiological heat stress. We also evaluated the phenotypic changes, including initial biofilm formation, acid production and ATP turnover of S. mutans during heat stress. We found that S. mutans responded to heat stress in a distinct pattern, which featured a differential transcription of 885 genes in total and 114 “core” transcripts throughout the six post-exposure time points investigated (5 min, 10 min, 15 min, 30 min, 45 min and 60 min). Further gene ontology analysis showed that transcriptional changes of genes involved in transcriptional regulation and cellular homeostasis were critical for heat stress responses of S. mutans. In addition to those highly conserved heat-shock proteins, we observed differential expression of multiple transcriptional regulators. The expression of genes involved in sugar transport, soluble glucans biosynthesis (gtfC) and binding (gbpC) were upregulated, whereas genes involved in ABC transporters, insoluble glucans biosynthesis (gtfB) and binding (gbpB), which are critical for biofilm skeleton, were either down-regulated or unchanged. These results together with enhanced glycolytic activity, attenuated sucrose-dependent initial attachment and impaired biofilm architecture indicate metabolic adaptations by this bacterium to compensate the extra energy demand for a better fitness under adverse conditions. We used time series microarrays to detect the dynamic changes of S. mutans under heat stress. Mid-logarithmic phase cell cultures of S. mutans (OD600nm = 0.5) were incubated at 42℃ for 5 min, 10 min, 15 min, 30 min, 45 min and 60 min, which were compared with the S. mutans cultured at 37℃. We applied three biological replicates at each time point.