High-throughput Method for Novel Medium Development for Culture of Anaerobic Gut Bacteria

Gut microbiota play important roles in the health of their host and detailed investigation of these organisms requires in vitro culture. Culturing strictly anaerobic bacteria can be a challenge as the gut environment they inhabit is nutritionally complex. Use of complex media containing nutritionally rich but undefined gut fluid reduces the accuracy of physiological and metabolomic studies. Here we present a high-throughput protocol for comparing growth rates of fastidiously anaerobic bacteria on different media. These protocols can be used to develop a solid medium made up of commercially sourced ingredients, providing replicable growth conditions for previously uncultured anaerobic bacteria. As many fastidious bacteria grow poorly in a liquid broth, these protocols measure bacterial growth rate on solid media. These protocols speed up and simplify the growth rate measurement process by using a multiwell format and equations in place of physical McFarland standards to calculate approximate cell density. Bacterial strains belonging to the families Erysipelotrichaceae and Lachnospiraceae (phylum Firmicutes) isolated from the hindgut of Kyphosus sydneyanus were used to demonstrate the efficacy of these protocols. Bacterial growth rates were compared between a nutritionally rich medium with gut fluid versus a novel replicable medium with mannitol. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Preparation of solid YCFA growth medium Basic Protocol 2: Collection of fish gut samples and plating to single isolates Basic Protocol 3: Genetic identification of single isolates with colony PCR and 16S rRNA gene sequencing Basic Protocol 4: Measurement of bacterial growth rates on solid media.

In Vitro Cultivation of the Syphilis Spirochete Treponema pallidum

For over a century, investigation of Treponema pallidum subsp. pallidum, the spiral‐shaped bacterium that causes syphilis, was hindered by an inability to culture the organism in vitro. A recent breakthrough has enabled continuous in vitro growth of this organism in co‐culture with mammalian tissue culture cells. This article contains the protocols needed to culture T. pallidum in the standard laboratory environment. In addition, protocols for growing and maintaining the required tissue culture cells, for generating isogenic strains by limiting dilution, and for quantitating T. pallidum by darkfield microscopy are included. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC.

Basic Protocol 1: In vitro cultivation of Treponema pallidum

Basic Protocol 2: Generation of isogenic strains

Support Protocol 1: Alternate harvest procedure

Support Protocol 2: Culture of Sf1Ep cells

Support Protocol 3: Assessment of T. pallidum number and viability

Laboratory Maintenance of Acinetobacter baumannii

Acinetobacter baumannii has recently drawn great interest in the microbiology research community due to the increase in clinical antibiotic resistance of this organism, and persistence of this bacterial species in the hospital environment. This unit outlines protocols for the growth and maintenance of A. baumannii in the laboratory.

Laboratory culture and maintenance of Stenotrophomonas maltophilia

Stenotrophomonas maltophilia is a ubiquitous soil bacterium that is increasingly recognized as an emerging nosocomial pathogen. This unit includes protocols for the in vitro growth and maintenance of S. maltophilia.