Draft Genome Sequences of 15 Bacterial Species Constituting the Stable Defined Intestinal Microbiota of the GM15 Gnotobiotic Mouse Model

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English. The GM15 community is a bacterial consortium used to generate a novel standardized mouse model with a simplified controlled intestinal microbiota recapitulating the specific opportunistic pathogen-free (SOPF) mouse phenotype and the potential to ensure an increased reproducibility and robustness of preclinical studies by limiting the confounding effect of microbiota composition fluctuation. T he intestinal microbiota is a complex and dynamic ecosystem largely composed of bacteria whose activity greatly impacts the health and diseases of the host (1). Associating mice with stable defined bacterial consortia reduces the complexity of the microbiota and overcomes limitations related to the variability between individuals and animal facilities (2, 3). Therefore, gnotobiotics contribute to standardization and experimental reproducibility and are a powerful tool for testing causality in host-microbiome studies (4-6). Thus, we have developed a simplified mouse microbiota that is representative of the fecal microbiota found in C57BL/6J mice on the functional level and derived a standardized gnotobiotic mouse model called GM15, which has been bred successfully for over eight generations in the gnotobiology unit of BIOASTER. All animal procedures were approved by the French Ministry of Higher Education, Research and Innovation (MESR) and the ANSES/ENVA/UPEC ethics committee (Autorisation de Projet Utilisant des Animaux à des Fins Scientifiques [APAFIS] no. 4529-2016022616404045v3, 785-2015042819315178v2, and 18918-2019020118003843v3) and were conducted in accordance with national French and European legislation on the protection of animals used for scientific purposes. We report here the draft genome sequences of 9 bacterial strains isolated from the intestinal microbiota of C57BL/6J specific-opportunistic-pathogen-free (SOPF) mice (Charles River Laboratories, France), 2 bacterial strains isolated from C57BL/6J axenic mice recolonized with feces of the altered Schaedler flora (ASF) mouse model (Taconic, USA), and 4 bacterial strains obtained from the DSMZ collection. Then, the colonization of the axenic C57BL/6J mice with these 15 bacterial isolates resulted in the GM15 mice. Fresh cecal contents and fecal pellets of mice were resuspended (1/10 [wt/vol]) in reduced broth medium for direct dilution plating onto agar plates (same medium as the broth) and growth at 37°C under an anaerobic atmosphere (90% N 2 , 5% H 2 , 5% CO 2). Lactobacillus johnsonii MD006 was isolated on MRS agar. Lactobacillus murinus MD040 and Parabacteroides goldsteinii MD072 were isolated on Columbia nalidixic acid (CNA) agar with 5% sheep blood. Bacteroides acidifaciens MD185 and Lachnospiraceae sp. strain MD308 were isolated on Gifu anaerobic medium (GAM) agar. Bacteroides caecimuris MD237 and Lactobacillus reuteri MD207 were isolated on GAM agar supplemented , respectively, with 32 g/ml vancomycin and 32 g/ml erythromycin. Lachno-spiraceae sp. strains MD335 and MD329 were isolated on M2GSC (modified Med2 of Citation Elie C, Mathieu A, Saliou A, Villain A, Darnaud M, Leulier F, Tamellini A. 2020. Draft genome sequences of 15 bacterial species constituting the stable defined intestinal microbiota of the GM15 gnotobiotic mouse model. Microbiol Resour