以下の講演会が　日本農芸化学会　北海道支部の補助を受け開催されます。
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　講演演題：Novel insight in the metabolism of dietary glycans and glycosides by human gut bacteria
　
　デンマーク工科大学（Technical University of Denmark）
准教授(Associate Professor)Maher Abou Hachem

日時：　2017年10月23日 15:30～1時間程度

場所：北海道大学農学部本館 S32室

講演概要
The human gut microbiota (HGM) comprises a similar or larger number of cells and at least a 150-fold larger metagenome as compared to the host.
The profound impact of this community on human health and metabolic homeostasis is well recognized. Specific microbiota signatures are associated with local and systemic disorders including irritable-bowel disease, obesity, type 2 diabetes and colon cancer. Metabolism of dietary glycans that are non-digestible by humans is an important selective force that modulates the composition and the metabolic output of the HGM.
The molecular mechanisms that enable specific taxa to specialize in metabolizing specific glycans or glyco-conjugates remain largely unexplored. Thousands of therapeutically active phytochemicals occur widely in vegetables, fruits, berries, nuts and beverages e.g. wine and tea. These compounds are typically glycosylated in planta, which reduces their biological activities and/or bioavailabilities. Notably, the taxa and metabolic routes involved in the conversion of these compounds in the human gut remain unexplored. We have recently performed the first molecular study to elucidate the metabolism of distinct plant glucosides and demonstrated how their bioconversion renders them bio-available to the host. Clostridium XIVa group Firmicutes are prevalent commensals that ferment carbohydrates to butyrate, which possesses anti-inflammatory and colorectal cancer protective effects. Our understanding of the competitiveness of this bacterial group is highly limited. To address this knowledge gap, we investigated the utilization of the common dietary fiber xylan by Roseburia intestinalis, an abundant member of this group. We demonstrated successful co-grows of this taxon on xylan in competition with dominant commensals from the Bacteroides genus. Uniquely, the study gave a snapshot into the molecular apparatus that contributes to establishing competitive metabolic niches that enable gut commensals to co-grow on dietary fibers. This novel insight makes a significant contribution to our functional knowledge on important, albeit underexplored facets of microbiota research. Highlights from these studies will be presented and discussed.

連絡先
　北海道大学大学院　農学研究院 生物化学研究室
　　佐分利　亘
　　saburiw@chem.agr.hokudai.ac.jp
　TEL & Fax：011-706-2508