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.
Project description:Background. Food can affect the microbial balance in the human intestine, and the ingestion of probiotics may play a role in the current obesity pandemic. The objective of our study was to determine if increased Lactobacillus spp. in the intestinal microflora of mice can promote growth and if changes in the intestinal microflora are associated with modifications in metabolism. Methodology. Female BALBc mice were divided between one control and two experimental groups and inoculated either once or twice with 4×1010 Lactobacillus per animal in PBS or with PBS alone. Fecal samples were collected and tested using qPCR to detect and quantify Lactobacillus spp., Bacteroidetes and Firmicutes. Gene expression by microarray and RT-PCR was studied in liver and adipose tissue. Finally, metabolic parameters in the plasma were tested. Principal Findings. In three independent experiments, we observed an increase in both weight gain and liver weight in mice inoculated with 4×1010 Lactobacillus. Inoculation with Lactobacillus sp. (ostrich) increased the Lactobacillus spp. and Firmicutes DNA copy number in feces. The transcriptional profile of liver tissue from mice inoculated with Lactobacillus sp. (ostrich) was enriched for Gene Ontology terms related to the immune response and metabolic modifications. The mRNA levels of fatty acyl synthase (Fas), sterol regulatory element binding factor 1 (Srebp1c), tumor necrosis factor alpha (Tnf), cytochrome P450 2E1 (Cyp2e1) and 3-phosphoinositide-dependent protein kinase-1 (Pdpk1) were significantly elevated in liver tissue in experimental group animals. In gonadal adipose tissue, the expression of leptin, peroxisome proliferator-activated receptor gamma (Pparg and Srebp1c was significantly higher in experimental group animals, whereas the expression of adiponectin was significantly lower. Conclusions. Alterations in the intestinal microbiota resulted in increased weight gain. Furthermore, increased Lactobacillus spp. in the intestinal microflora of mice inoculated with Lactobacillus sp. (ostrich) resulted in accelerated weight gain, liver enlargement and metabolic changes in the plasma, liver and adipose tissue.
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: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 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: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:We used a whole genome array containing 97.4 % of the annotated genes of Lactobacillus acidophilus NCFM, a probiotic culture that belongs to the lactic acid bacteria group, to identify genes that are differentially expressed under several stress conditions. Keywords: Stress response
Project description:The hypocholesterolemic effect of probiotics has been observed, but the molecular mechanism of probiotic-host interaction is still obscure. In this study, DNA microarray technology was used to explore the gene expression profile of liver of hypercholesterolemic rats caused by administration of probiotic Lactobacillus casei Zhang, which can decrease the serum triglyceride, low-density lipoprotein cholesterol, hepatic cholesterol and triglyceride of hypercholesterolemic rats.
Project description:This project investigated the role of lipoproteins in immune signaling by the model probiotic Lactobacillus plantarum, by mutagenesis of the prolipoprotein diacylglyceryltransferase encoding lgt gene involved in lipoprotein acylation.