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bioRxiv · 10.1101/290353

Changes in the genetic requirements for microbial interactions with increasing community complexity

Morin, M.·Pierce, E. C.·Dutton, R. J.
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Abstract

Microbial community structure and function rely on complex interactions whose underlying molecular mechanisms are poorly understood. To investigate these interactions in a simple microbiome, we introduced E. coli into an experimental community based on a cheese rind and identified the differences in E. colis genetic requirements for growth in interactive and non-interactive contexts using Random Barcode Transposon Sequencing (RB-TnSeq) and RNASeq. E. colis genetic requirements varied among pairwise growth conditions and between pairwise and community conditions. Our analysis points to mechanisms by which growth conditions change as a result of increasing community complexity and suggests that growth within a community relies on a combination of pairwise and higher order interactions. Our work provides a framework for using the model organism E. coli as a probe to investigate microbial interactions regardless of the genetic tractability of members of the studied ecosystem.

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Morin, M., Pierce, E. C., Dutton, R. J.. 2018-03-28. Changes in the genetic requirements for microbial interactions with increasing community complexity. https://doi.org/10.1101/290353

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