The colonization characteristics of gut bacteria in the intestinal tract are important to understand their potential survival strategies. Bacterial surface adhesion factors are known to be the predominant bacterial molecules involved in hostmicrobe interaction. Moonlighting refers to the ability of proteins to exert multiple biologically important functions in gut bacteria. The moonlighting proteins have canonical functions in essential cellular processes, such as glycolysis, chaperone activity, and protein synthesis, whereas in their cytoplasmic form, following secretion and localization to the cell surface, they often exert additional functions as an adhesion factor. Here we review the moonlighting proteinmediated colonization process of the gut bacteria, with a focus on the elongation factor Tu (EF-Tu). In addition, we will introduce a new experimental method for evaluating the behavior of moonlighting proteins in vivo.

The terms “Probiotics” and “Prebiotics” which represent beneficial microbes and beneficial food substances for human health, respectively, have been used for several decades since they were firstly developed. The original ideas showing the importance of the gut microbiota for health were already argued more than a hundred years ago, and since then many efforts to demonstrate and practice the actual beneficial effects of certain microbes and substances have been implemented by a huge number of investigators. In this review article, I would like to summarize the history of argument of the concepts and definitions for “Probiotics” and “Prebiotics”, and see how we can find appropriate ways to reach future consensus.

Awa-bancha, a traditional tea in Tokushima, Japan, is produced by immersing boiled tea leaves in a tub containing microorganisms and allowing fermentation. In the present study, tea fermentation was prepared with Lactobacillus pentosus OLL203984 isolated from Awa-bancha pickle solution and the effect of this tea fermentation on bowel function and gut microbiota was evaluated in Ncx/Hox11L.1-deficient (Ncx-/-) mice presenting with delayed gastrointestinal transit time. Ncx-/- mice were orally administered tea fermentation or water as a control for 4 weeks.

Gastrointestinal transit time was significantly shorter in mice that ingested tea fermentation than those that ingested water, whereas there was no significant between-group difference in fecal water content. Fecal Bacteroidales and Closridiales decreased significantly, while Lactobacillales and Bifidobacteriales increased significantly, and Shannon index, which is one of the indices used to measure alpha diversity, decreased significantly, after ingestion of tea fermentation. In contrast, these bacterial proportion and Shannon index were unchanged in the control group. The level of colonic expression of iNOS mRNA, which encodes a protein involved in bowel motility, tended to be lower in the tea fermentation-treated than in the control group. These results suggest that ingestion of tea fermented with L.

pentosus OLL203984 alters gut microbiota composition and ameliorates delayed gastrointestinal transit time.