A key question in microbial ecology is what the driving forces behind the persistence of large biodiversity in natural environments are. We studied a microbial community with more than 100 different types of species which evolved in a 15-years old bioreactor with benzene as the main carbon and energy source and nitrate as the electron acceptor. Using genome-centric metagenomics plus metatranscriptomics, we demonstrate that most of the community members likely feed on metabolic left-overs or on necromass while only a few of them, from families Rhodocyclaceae and Peptococcaceae, are candidates to degrade benzene. We verify with an additional succession experiment using metabolomics and metabarcoding that these few community members are the actual drivers of benzene degradation. As such, we hypothesize that high species richness is maintained and the complexity of a natural community is stabilized in a controlled environment by the interdependencies between the few benzene degraders and the rest of the community members, ultimately resulting in a food web with different trophic levels.
Bibliographical noteFunding Information:
We thank Laura Luzia, Frank Bruggeman, Bas Teusink and Bastian Hornung for their significant contribution with discussions and proofreading. Evelina Tutucci, Paul Iturbe Espinoza, Philipp Savakis and Huub J. M. Op den Camp for helpful discussions. We are grateful to the late Wilfred F.M. Röling for his scientific input on experimental design. Unfortunately, he passed away before this work was published. This study was supported by a grant of BE-Basic-FES funds from the Dutch Ministry of Economic Affairs. The research of CM is supported by a Grand Solution grant from Innovation Fund Denmark (grant no. 6150-00033B), The FoodTranscriptomics project.
© 2021, The Author(s).
Copyright 2021 Elsevier B.V., All rights reserved.