Project description:To determine whether osmotic pressure affects the translation efficiency of Lactobacillus rhamnosus, the ribosome profiling assay was performed to analyze the changes in translation efficiency in L. rhamnosus ATCC 53103. Under osmotic stress, differentially expressed genes (DEGs) involved in fatty acid biosynthesis and metabolism, ribosome, and purine metabolism pathways were co-regulated with consistent expression direction at translation and transcription levels. DEGs involved in the biosynthesis of phenylalanine, tyrosine, and tryptophan, and the phosphotransferase system pathways also were co-regulated at translation and transcription levels, while they showed opposite expression direction at two levels. Moreover, DEGs involved in the two-component system, amino acid metabolism, and pyruvate metabolism pathways were only regulated at the transcription level. And DEGs involved in fructose and mannose metabolism were only regulated at the translation level. The translation efficiency of DEGs involved in the biosynthesis of amino acids was downregulated while in quorum sensing and PTS pathways was upregulated. In addition, the ribosome footprints accumulated in open reading frame regions resulted in impaired translation initiation and elongation under osmotic stress. In summary, L. rhamnosus ATCC 53103 could respond to osmotic stress by translation regulation and control the balance between survival and growth of cells by transcription and translation.
Project description:The presence of tagatose in Lactobacillus rhamnosus strain GG caused induction of a large number of genes associated with carbohydrate metabolism including the phosphotransferase system. In addition, these results indicate the tagatose enhanced the growth of Lactobacillus casei 01 and Lactobacillus rhamnosus strain GG and their probiotic activities by activating tagatose-associated PTS networks. Two-condition experiment, Lactobacillus rhamnosus GG with glucose vs. Lactobacillus rhamnosus GG with tagatose. For preparing the total RNA, Lactobacillus rhamnosus GG cells were grown at 37M-BM-0C in prebiotic minimum medium supplemented with 2% glucose or tagatose for 24 h.
Project description:Transcriptional profiling of probiotic Lactobacillus rhamnosus strain GG mid-exponential pH-controlled bioreactor cultures before and after exposure to bovine bile (0.2% ox gall). Keywords: bile, stress response Cell samples from four biological replicates were harvested right before (time point 0 min) and 10, 30 and 120 min after bile treatment. Each sample was compared to a common reference sample (time point 0 min, mid-exponential growth phase Lactobacillus rhamnosus GG cultures). A total of 12 hybridizations were performed using balanced dye-swap design. Dyes were balanced between compared sample pairs and between biological replicates.
Project description:Transcriptional profiling of probiotic Lactobacillus rhamnosus strain GG mid-exponential pH-controlled bioreactor cultures before and after exposure to bovine bile (0.2% ox gall). Keywords: bile, stress response
Project description:The presence of tagatose in Lactobacillus rhamnosus strain GG caused induction of a large number of genes associated with carbohydrate metabolism including the phosphotransferase system. In addition, these results indicate the tagatose enhanced the growth of Lactobacillus casei 01 and Lactobacillus rhamnosus strain GG and their probiotic activities by activating tagatose-associated PTS networks.
Project description:Transcriptional profiling of probiotic Lactobacillus rhamnosus GG during growth in industrial-type whey medium in pH-controlled bioreactor cultures at two different growth pH: 4.8 and 5.8. Keywords: growth phase, growth pH
Project description:The present study reports comparative surfacomics (study of cell-surface exposed proteins) of the probiotic Lactobacillus rhamnosus strain GG and the dairy strain Lc705.