This mirrors work showing aggregates more effectively capture extracellular metabolites (doi.org/10.1371/jour...) and that flocculation improves crossfeeding (doi.org/10.1038/s415...)! Thus, the benefits of synthetic flocculation could relate more to metabolite sharing than diffusion limitations.
The preprint from my work @mokhalil.bsky.social and Mary Dunlop's groups at BU is out on bioRxiv! As new tools come online to engineer multicellularity, we asked: how does sticking cells together into larger groups affect their fitness and function?
We hypothesize that the reversibility of FLO1 adhesion, which allows cells to exchange places, improves mass transport to the aggregate center, limiting a large source of either costs or benefits. In this way, synthetic flocs could be a powerful chassis for multicellular designs.
Unexpectedly, we did not find evidence of large costs or benefits! Synthetic flocs grew exponentially and stably aggregated for 100s of generations. In ethanol and other toxins, they were as susceptible as our unicellular control.
Overall, non-specific and multivalent adhesion could be a powerful tool for constructing aggregates, and improved growth in nutrient-limited settings are a promising new application. Check out the full preprint here! www.biorxiv.org/content/10.6...