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Title Comparative Genomic and Phenotypic Analysis of the Vaginal Probiotic Lactobacillus Rhamnosus GR-1
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Type Poster Presentation |
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Theme Probiotics and Prebiotics: Excellence in Science and Clinical Translation |
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Topic Metabolic By-products of Probiotic Strains |
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Main Author Mariya Petrova1 2 |
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Presenting Author Mariya Petrova1 2 |
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Co-Author Jean Macklaim4 Sander Wuyts2 Gregory Gloor4 Sarah Lebeer1 2 Gregor Reid3 5 |
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Department / Institution / Country CMPG / KU Leuven / Belgium1 Department of Bioscience Engineering / University of Antwerp / Belgium2 Lawson Health Research Institute / Canadian Research and Development Centre for Human Microbiome and Probiotics / Canada3 Departments of Biochemistry / The University of Western Ontario / Canada4 Department of Microbiology and Immunology / The University of Western Ontario / Canada5 |
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Background and Rationale Lactobacillus represents a versatile bacterial genus, which can adapt to a wide variety of ecological niches, including human body sites such as the intestinal and urogenital tract. While the genome sequences of various gastrointestinal and dairy probiotic Lactobacillus strains have been published since 2004, the vaginal strains are lagging behind. Nevertheless, probiotic application holds greater promise in the vagina, because of the dominance of lactobacilli in the niches under health conditions. |
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Objectives: Indicates the purpose of the study In this study, the complete genome sequence of the vaginal probiotic L. rhamnosus GR-1 was determined and compared to other L. rhamnosus strains at genomic and phenotypic level. The strain LGR-1 was originally isolated from a female urethra and was assessed with L. rhamnosus GG from a feces sample of a healthy male, and L. rhamnosus LC705 from a dairy product. |
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Methodology: Describe pertinent experimental procedures First, the genome of LGR-1 was determined, followed by calculating the pan-genome of all publicly available L. rhamnosus strains and constructing a high-resolution phylogenetic tree. Subsequently, the phenotypic differences between LGR-1, LGG, and LC705 were evaluated by performing various experiments, such as carbohydrate utilization, adhesion to epithelial cells, detection of pili and EPS molecules, as well as different stress survival assays. |
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Results: Summarize the results of the research A key difference is the absence in GR-1 and LC705 of the spaCBA locus required for pili-mediated intestinal epithelial adhesion. Also, the LGR-1 genome contains a unique cluster for EPS production, which is postulated to synthesize glucose-rich, rhamnose-lacking exopolysaccharide molecules that are different from the galactose-rich EPS of LGG. Compared to LGG, LGR-1 was also genetically predicted and experimentally shown to better metabolize lactose and maltose, and to better withstand oxidative stress, which is of relevance in the vagina |
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Conclusions: State the main conclusions Ultimately, this study could thus provide a molecular framework for the selection of the optimal probiotic strain for each targeted niche and condition |