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Jacob Moran

@jacobmoran.bsky.social

Pioneer Fellow at UMich EEB in Luis Zaman's lab. Former Biophysics postdoc in Kevin Wood's lab. PhD in Physics at WashU with Mikhail Tikhonov. Special interests: biological physics, microbial eco-evo, tacos, espresso, yoga. He/him

Posts Replies Media

Jacob Moran @jacobmoran.bsky.social · 05/05/2026

I want to thank Mike Hinczewski, @surajshankar.bsky.social, Bob Woods, and @luiszaman.bsky.social for all their guidance and support on this work! And I want to show my deep gratitude for the late @kevinwoodum.bsky.social who sadly is no longer with us - thank you Kevin for so much!

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

Happy belated #MayThe4th — may the (diffusive) forces be with you🌀

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

More broadly: We developed an experimental platform for linking structures at the single- and multi-colony scales to ecological interactions mediated at the cellular scale, enabling a more systematic view of cross-scale organization

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

Takeaway: Even “clonal” populations can act antagonistically Self-inhibition may be a general driver of structure in microbial communities

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

We tested this with a simple “spent-agar” assay: Grow cells → remove agar → add fresh nutrients + new cells Result: no growth → something inhibitory is left behind

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

Crucially, the model therefore predicts the presence of some form of direct growth inhibition present in the experiments...

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

We then asked: can nutrient competition alone explain this? Short answer: no. A simple model shows you need TWO ingredients: • resource competition • direct growth inhibition Together, they produce four distinct spatial phases of colony interactions

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

Two key observations: • Gap size depends on BOTH spacing + nutrients • Colony shape (rough vs smooth) depends mostly on nutrients → different scales, different controls

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

We built a high-throughput platform (robotics + time-lapse imaging with document scanners) to systematically study how colony interactions depend on: • initial spacing • nutrient levels

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

This so called "sibling rivalry" is common across species and conditions - but in many cases it isn't clear what is driving gap formation. So we asked: what minimal ingredients explain this multi-colony structure?

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

When identical bacterial colonies grow near each other, they don't always merge. Often, they form stable "no-man's lands" - gaps with little to no cells at all. For now we have focused on Enterococcus faecalis - a bug for which this behavior has not been studied.

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Jacob Moran @jacobmoran.bsky.social · 05/05/2026

Excited to share our new preprint! In honor of May the 4th: a story about bacterial Clone Wars in space! Preprint: www.biorxiv.org/content/10.6...

biorxiv.org

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