Crossfeeding interactions in a minimal marine chitin-degrading community
- 1ETH Zurich
Abstract
Communities of heterotrophic particle-associated marine bacteria contribute to oceanic carbon cycling through interspecies interactions that can influence polysaccharide degradation. While these interactions have been extensively studied using single natural isolates or pairwise combinations thereof, their mechanistic relevance within multispecies communities remains unclear. To address this gap, we developed MCC4, a minimal chitin-degrading bacterial community consisting of two chitin degraders and two non-degrading isolates that represent globally prevalent marine bacterial taxa. We show that the community remains stable across ten growth-dilution cycles, establishing a reproducible model for controlled multi-isolate experiments. Using transcriptomic and metabolomic analyses combined with metabolite supplementation assays, we uncovered the underlying crossfeeding network. While one degrader drives chitin degradation, the other exploits chitin monomers and chitooligomers generated by the main degrader. The two non-degraders are sustained by consuming deacetylated chitin monomers, 2-carbon compounds, nucleotides, and branched-chain amino acids, likely released by degraders. Community assembly is driven by competitive scavenging abilities, potentially complemented by specific survival strategies such as increased motility and deployment of type VI secretion systems. Despite its simplicity, MCC4 captures dynamic microbial interactions characteristic of natural marine ecosystems. It offers a tractable, reproducible framework for investigating how environmental perturbations impact community function and testing ecological theories in particle-associated marine environments.
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BibTeX
@misc{haavisto2026crossfeeding,
title = {{Crossfeeding interactions in a minimal marine chitin-degrading community}},
author = {V. Haavisto and U. Sauer},
howpublished = {bioRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.28.762472},
url = {https://www.biorxiv.org/content/10.64898/2026.10.28.762472v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - Crossfeeding interactions in a minimal marine chitin-degrading community
AU - V. Haavisto
AU - U. Sauer
PY - 2026
DA - 2026/10/28
PB - bioRxiv
DO - 10.64898/2026.10.28.762472
UR - https://www.biorxiv.org/content/10.64898/2026.10.28.762472v1
AB - Communities of heterotrophic particle-associated marine bacteria contribute to oceanic carbon cycling through interspecies interactions that can influence polysaccharide degradation. While these interactions have been extensively studied using single natural isolates or pairwise combinations thereof, their mechanistic relevance within multispecies communities remains unclear. To address this gap, we developed MCC4, a minimal chitin-degrading bacterial community consisting of two chitin degraders and two non-degrading isolates that represent globally prevalent marine bacterial taxa. We show that the community remains stable across ten growth-dilution cycles, establishing a reproducible model for controlled multi-isolate experiments. Using transcriptomic and metabolomic analyses combined with metabolite supplementation assays, we uncovered the underlying crossfeeding network. While one degrader drives chitin degradation, the other exploits chitin monomers and chitooligomers generated by the main degrader. The two non-degraders are sustained by consuming deacetylated chitin monomers, 2-carbon compounds, nucleotides, and branched-chain amino acids, likely released by degraders. Community assembly is driven by competitive scavenging abilities, potentially complemented by specific survival strategies such as increased motility and deployment of type VI secretion systems. Despite its simplicity, MCC4 captures dynamic microbial interactions characteristic of natural marine ecosystems. It offers a tractable, reproducible framework for investigating how environmental perturbations impact community function and testing ecological theories in particle-associated marine environments.
ER -