Probiotics, Prebiotics, and New FoodsResponse of Lactic Acid Bacteria to the Digestive EnvironmentMater, Denis D. G PHD; Corthier, Gerard PHDAuthor Information From Unité d’écologie et de Physiologie du Système Digestif, Institut National de la Recherche Agronomique, Jouy-en-Josas, France. Received for publication January 13, 2004; accepted February 12, 2004. Reprints: Gerard Corthier, Unité d’écologie et de Physiologie du Système Digestif, Institut National de la Recherche Agronomique, F-78350, Jouy-en-Josas, France (e-mail: [email protected]). Journal of Clinical Gastroenterology: July 2004 - Volume 38 - Issue - p S64-S66 doi: 10.1097/01.mcg.0000128930.37156.71 Buy Metrics Abstract Background: This article reviews several studies regarding adaptation to the digestive environment by lactic acid bacteria. The behavior of lactic acid bacteria in the digestive tract is worth investigating, and bacterial physiologic changes remain to be examined. Methods: A genetic approach based on the fusion of bacterial promoters with genes of the reporter protein luciferase is described to screen for functions that lactic acid bacteria may suppress or activate in the digestive environment. Results: Variations in luciferase expression from different promoters were observed in the digestive tract of mice models. In some cases, the promoter could be activated in response to an inducer provided with the diet. Conclusion: These data suggest that lactic acid bacteria are metabolically active in the digestive tract and can synthesize proteins to adapt to the digestive environment. © 2004 Lippincott Williams & Wilkins, Inc.