Cultivation of the Oligo-Mouse-Microbiota OMM12 in the peristaltic mixed tubular bioreactor PETR

Abstract

The intestinal microbiota plays a crucial role in human health and disease, and is therefore of great interest in various research areas. However, studies with humans are limited and difficult to control, leading to a growing demand for sophisticated bioreactor systems that can mimic human intestinal conditions in vitro. The main objective of this study is to compare the in vitro growth of a defined microbiota in the recently published PEristaltic mixed Tubular bioReactor (PETR) with previously published in vivo data for the same microbiota. PETR simulates various colonic conditions, including peristaltic mixing, dialytic water and metabolite removal, and a temporally constant and longitudinally progressive pH gradient in a continuously operated tubular bioreactor. The Oligo-Mouse-Microbiota OMM¹² was chosen as model microbiota and consists of 12 bacteria representing the major phyla of the mouse intestine. During 10 d continuous cultivation in PETR, community composition was regularly analyzed using strain-specific qPCR. The results were consistent with the formation of organic acids measured by HPLC. After approximately 6 d, the optical density, concentrations of organic acids, and the microbiota composition remained relatively stable. Despite the different intestinal conditions of humans and mice, several similarities between reactor cultivation and gnotobiotic mouse model confirm PETR as a suitable system for microbiota research.