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bioRxiv · 10.1101/2020.12.07.415638

BIOME-Preserve: A Novel Storage and Transport Medium for Preserving Anaerobic Microbiota Samples for Culture Recovery

Abstract

Culture-based study design is critical to advance research into the relationship between human health and the microbiome. Traditional sample collection protocols are focused on preserving nucleic acids and metabolites and are largely inappropriate for preserving sensitive anaerobic bacteria alive for later culture recovery. Here we introduce a novel microbiome preservation kit (BIOME-Preserve) that facilitates recovery of anaerobic organisms from human stool held at room temperature. Using a combination of culture recovery and shallow whole-genome shotgun sequencing, we characterized the culturable anaerobes from fresh human stool and from human stool held in BIOME-Preserve for up to 120 hours. We recovered several species of interest to microbiome researchers, including Bifidobacterium spp., Bacteroides spp., Blautia spp., Eubacterium halii, Akkermansia muciniphila, and Faecalibacterium prausnitzii. Together, our results suggest BIOME-Preserve is practical for the collection, transport, and culture of anaerobic bacteria from human samples and can help provide the foundation for culture collections that can be used in further research and in the development of microbiome-based therapeutics. ImportanceSequencing-based protocols for studying the human microbiome have unearthed a wealth of information about the relationship between the microbiome and human health. But these microbes cannot be leveraged as therapeutic targets without culture-based studies to phenotype species of interest and to establish culture collections for use in animal models. Contrary to popular opinion, most gastrointestinal bacteria can be cultured, yet most sample collection strategies are optimized for the preservation of nucleic acids and/or metabolites only and do not take into account considerations for preserving oxygen-sensitive anaerobes and facultative anaerobes, which comprise the majority of the human gut microbiome. A human microbiome sample transport and preservation medium such as the one described here can play an important role in enabling researchers to better understand the link between the microbiome and human health and how to leverage that link through novel microbiome-based therapeutics.

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BibTeXRIS

Hyde, E. R., Lozano, H., Cox, S.. 2020-12-08. BIOME-Preserve: A Novel Storage and Transport Medium for Preserving Anaerobic Microbiota Samples for Culture Recovery. https://doi.org/10.1101/2020.12.07.415638

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