雙歧桿菌（有時作為“益生菌”用在酸奶和其他食物產(chǎn)品中）是人腸道中的天然細(xì)菌,，已知能保護(hù)我們不發(fā)生感染?，F(xiàn)在，關(guān)于這種保護(hù)作用的至少一部分的一個可能機(jī)制已以醋酸鹽的形式被發(fā)現(xiàn),。讓小鼠口服“長雙歧桿菌”的一個亞型,，似乎能保護(hù)它們不被有潛在致命性的大腸桿菌O157:H7感染，因為它能促進(jìn)上皮細(xì)胞中的宿主防衛(wèi)機(jī)制,。（生物谷Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature09646
Bifidobacteria can protect from enteropathogenic infection through production of acetate
Shinji Fukuda,Hidehiro Toh,Koji Hase,Kenshiro Oshima,Yumiko Nakanishi,Kazutoshi Yoshimura,Toru Tobe,Julie M. Clarke,David L. Topping,Tohru Suzuki,Todd D. Taylor,Kikuji Itoh,Jun Kikuchi,Hidetoshi Morita,Masahira Hattori& Hiroshi Ohno
The human gut is colonized with a wide variety of microorganisms, including species, such as those belonging to the bacterial genus Bifidobacterium, that have beneficial effects on human physiology and pathology1, 2, 3. Among the most distinctive benefits of bifidobacteria are modulation of host defence responses and protection against infectious diseases4, 5, 6. Nevertheless, the molecular mechanisms underlying these effects have barely been elucidated. To investigate these mechanisms, we used mice associated with certain bifidobacterial strains and a simplified model of lethal infection with enterohaemorrhagic Escherichia coli O157:H7, together with an integrated ‘omics’ approach. Here we show that genes encoding an ATP-binding-cassette-type carbohydrate transporter present in certain bifidobacteria contribute to protecting mice against death induced by E. coli O157:H7. We found that this effect can be attributed, at least in part, to increased production of acetate and that translocation of the E. coli O157:H7 Shiga toxin from the gut lumen to the blood was inhibited. We propose that acetate produced by protective bifidobacteria improves intestinal defence mediated by epithelial cells and thereby protects the host against lethal infection.
