Project description:Background: In prokaryotes, sigma factors are essential for the targeting of the transcription machinery to promoters. Various sigma factors have been described that recognize and bind to specific DNA sequence motifs in promoter sequences. The canonical sigma factor σ70 is commonly involved in transcription of the cell's general housekeeping genes, which is mediated by the conserved σ70 promoter sequence motifs. This study detects and predicts the general σ70-promoter sequences in Lactobacillus plantarum WCFS1 using genome-wide analysis. The accuracy of the transcriptionally-active part of this promoter prediction was subsequently evaluated by correlating locations of predicted promoters with experimentally detected transcription starts sites (TSSs) using high-resolution tiling array transcriptome datasets. Results: To identify σ70-related promoter sequences, we performed a genome-wide sequence motif scan of the L. plantarum WCFS1 genome focusing on the regions upstream of protein-encoding genes. We obtained several highly conserved motifs including those resembling the conserved σ70-promoter consensus. Position weight matrices-based models of the recovered σ70-promoter sequence motif were employed to identify 4746 motifs with significant similarity (p-value < 10-4) to the model-motif in the L. plantarum genome. Genome-wide transcription start site information deduced from whole genome tiling-array transcriptome datasets revealed 936 TSSs that were employed to validate the transcriptionally active fraction of these predicted promoters. In total, 578 predicted promoters were found in proximity (≤ 100 nucleotides) of the identified TSSs, showing a highly significant co-occurrence of predicted promoter and measured TSS (p-value < 10-23). An additional 224 predicted promoters was validated when the significant similarity to the model-motif was applied less strictly (10-4 ≤ p-value < 10-3). Conclusions: High-resolution tiling arrays provide a suitable source for TSS detection at a genome-wide level, and allow experimental verification of in silico-predicted promoter sequence motifs.
Project description:Whole genome transcriptional profiling was used to characterize the response of Lactobacillus plantarum WCFS1 human isolate during challenge with oleuropein. Twelve independent experiments were performed and mixed at random in groups of four for total of three RNA samples. The transcriptional profile shows that Lactobacillus plantarum WCFS1 adapts its metabolic capacity to acquire certain carbohydrates and repress the expression of genes involved in fatty acid biosyntheis. The transcriptomic datasets also revealed the downregulation of genes related to the biosynthesis of capsular polysaccharides and genes coding for ABC-type transporters. In addition, induction of oligopeptide permeases is also part of the response of Lactobacillus plantarum WCFS1 to oleuropein.
Project description:Transcriptome profiles of control Lactobacillus plantarum WCFS1 cells were compared with 8% ethanol adapted cells and with 10 min or 30 min 8% ethanol shocked cells.
Project description:In order to understand LBG derived galacto-manno-oligosaccharides utilization by a probiotic bacterium, Lactobacillus plantarum WCFS1, we have grown Lactobacillus plantarum WCFS1 (in duplicates) till mid log phase (OD600nm ~0.5, 10 h) in carbon free MRS (de Man, Rogosa Sharpe ) media containing either galacto-manno-oligosaccharides, mannose, glucose or galactose (1% w/v) as the sole carbon source.
Project description:Lactobacillus plantarum was grown anaerobically on 4 different sugars (Mannose Lactose Fructose and Sucrose) to OD600 = 1.0. Samples were compared with a similar grown culture on glucose. An independnet biological duplicate of tht experimnet was performed (samples 1 and 2). L. plantarum WCFS1 grown in glucose, mannose, fructose, and sucrose
Project description:Background: In prokaryotes, sigma factors are essential for the targeting of the transcription machinery to promoters. Various sigma factors have been described that recognize and bind to specific DNA sequence motifs in promoter sequences. The canonical sigma factor M-OM-^C70 is commonly involved in transcription of the cell's general housekeeping genes, which is mediated by the conserved M-OM-^C70 promoter sequence motifs. This study detects and predicts the general M-OM-^C70-promoter sequences in Lactobacillus plantarum WCFS1 using genome-wide analysis. The accuracy of the transcriptionally-active part of this promoter prediction was subsequently evaluated by correlating locations of predicted promoters with experimentally detected transcription starts sites (TSSs) using high-resolution tiling array transcriptome datasets. Results: To identify M-OM-^C70-related promoter sequences, we performed a genome-wide sequence motif scan of the L. plantarum WCFS1 genome focusing on the regions upstream of protein-encoding genes. We obtained several highly conserved motifs including those resembling the conserved M-OM-^C70-promoter consensus. Position weight matrices-based models of the recovered M-OM-^C70-promoter sequence motif were employed to identify 4746 motifs with significant similarity (p-value < 10-4) to the model-motif in the L. plantarum genome. Genome-wide transcription start site information deduced from whole genome tiling-array transcriptome datasets revealed 936 TSSs that were employed to validate the transcriptionally active fraction of these predicted promoters. In total, 578 predicted promoters were found in proximity (M-bM-^IM-$ 100 nucleotides) of the identified TSSs, showing a highly significant co-occurrence of predicted promoter and measured TSS (p-value < 10-23). An additional 224 predicted promoters was validated when the significant similarity to the model-motif was applied less strictly (10-4 M-bM-^IM-$ p-value < 10-3). Conclusions: High-resolution tiling arrays provide a suitable source for TSS detection at a genome-wide level, and allow experimental verification of in silico-predicted promoter sequence motifs. Triplicate hybridizations (technical replicates) of two L. plantarum WCFS1 samples (biological replicates) gathered from a fermentation run at OD600 of 1. Dye swap applied to one of the three technical replicates.
Project description:Transcriptome profiles of control Lactobacillus plantarum WCFS1 cells were compared with ctsR, hrcA, and ctsR-hrcA deletion mutants grown in MRS media at 28 and 40 degrees Celcius.