Tunable population dynamics in a synthetic filamentouscoculture.

Finger M, Palacio-Barrera AM, Richter P, Schlembach I, Büchs J, Rosenbaum MA (2022) Tunable population dynamics in a synthetic filamentouscoculture. Open Microbiol J 11(5), e1324.

Abstract

Microbial cocultures are used as a tool to stimulate natural product biosynthesis.However, studies often empirically combine different organisms without a deeperunderstanding of the population dynamics. As filamentous organisms offer a vastmetabolic diversity, we developed a model filamentous coculture of the cellulolyticfungusTrichoderma reeseiRUT‐C30 and the noncellulolytic bacteriumStreptomycescoelicolorA3(2). The coculture was set up to useα‐cellulose as a carbon source. Thisestablished a dependency ofS. coelicoloron hydrolysate sugars released byT. reeseicellulases. To provide detailed insight into coculture dynamics, we applied high‐throughput online monitoring of the respiration rate and fluorescence of the taggedstrains. The respiration rate allowed us to distinguish the conditions of successfulcellulase formation. Furthermore, to dissect the individual strain contributions,T.reeseiandS. coelicolorwere tagged with mCherry and mNeonGreen (mNG)fluorescence proteins, respectively. When evaluating varying inoculation ratios, itwas observed that both partners outcompete the other when given a highinoculation advantage. Nonetheless, adequate proportions for simultaneous growthof both partners, cellulase, and pigment production could be determined. Finally,population dynamics were also tuned by modulating abiotic factors. Increasedosmolality provided a growth advantage toS. coelicolor. In contrast, an increase inshaking frequency had a negative effect onS. coelicolorbiomass formation,promotingT. reesei. This comprehensive analysis fills important knowledge gaps inthe control of complex cocultures and accelerates the setup of other tailor‐madecoculture bioprocesses.

Leibniz-HKI-Authors

Miriam Agler-Rosenbaum
Ana Barrera
Ivan Schlembach

Identifier

doi: 10.1002/mbo3.1324

PMID: 36314761