TY - JOUR T1 - GI highlights from the literature JF - Gut JO - Gut SP - 181 LP - 182 DO - 10.1136/gutjnl-2014-308700 VL - 64 IS - 1 AU - Mairi H McLean Y1 - 2015/01/01 UR - http://gut.bmj.com/content/64/1/181.abstract N2 - Can we understand how the gut microbiota is established? ▸ Seedorf H, Griffin NW, Ridaura VK, et al. Bacteria from diverse habitats colonise and compete in the mouse gut. Cell 2014;159:253–66. How microbes establish themselves within our GI tract and how our interactions with other humans, animals and our environment impacts on this colonisation remains unknown. Understanding how microbes establish themselves could provide strong clues as to how our gut microbiota shapes our health, and potentially could identify how well-defined species consortia (microbiota-directed therapeutics) could be beneficial. In this study, bacteria from several foreign environments were used to colonise germ-free mice, and their ability to metabolise dietary and host carbohydrates and bile acids were measured. The findings demonstrate that the mouse intestinal tract, while highly selective, shows unanticipated patterns of ecological succession. Nonetheless, cohousing the various colonised mice revealed that most bacterial phylotypes, including those from the human gut, were not capable of effectively colonising a gut harbouring an autochthonous microbiota. These studies illustrate how patterns of colonisation succession cannot be predicted purely on habitat associations. Using a trio cohousing approach they demonstrated that human gut microbes could colonise germ-free mice more rapidly than mouse-derived taxa. The success of colonisation could be correlated with functional features of the community and host. The present study assessed bacteria from extremely broad environmental niches including human skin and tongue, zebra fish, termite gut, soil and estuarine microbial mats; providing confidence that the approach could be generalised to address the current issues relating to the use of microbiota-derived therapeutics. Assessing the patterns of colonisation/succession of these products is vital to allow us to identify which organisms are beneficial or detrimental to re-gaining health. This study provides a useful framework for studies that require consideration of the microbial potential of planned biological interventions. Stromal Indian Hedgehog signalling is required for adenoma formation in mice ▸ Büller NV, Rosekrans SL, Metcalfe C, et al. … ER -