What the study found
Porphyromonas gingivalis, a pathogen involved in periodontitis, shows a quorum threshold for growth, but it can persist at low abundance under some conditions. The study found that Veillonella parvula can lower the growth threshold for P. gingivalis, and that microenvironmental noise can help it persist below that threshold.
Why the authors say this matters
The authors conclude that ecological interactions and stochastic effects help explain how P. gingivalis persists in the mouth. They also suggest that interventions reducing facilitation could limit P. gingivalis-associated inflammation.
What the researchers tested
The researchers combined quantitative growth experiments with mathematical modeling. They used a cubic Allee-effect model, stochastic extensions, Fokker-Planck analysis, long-term subthreshold experiments, Pg-Vp co-cultures, and a two-species replicator model.
What worked and what didn't
Conditioned medium from V. parvula lowered the quorum threshold, indicating early-colonizer facilitation. Stochastic modeling showed that noise can allow persistence below the Allee barrier, and this matched long-term experiments showing persistent survival at subthreshold levels. In co-culture, replicate outcomes included rescue for subcritical inocula, while V. parvula reliably reached capacity and the terminal outcomes within the experimental window were coexistence or P. gingivalis extinction.
What to keep in mind
The abstract does not describe detailed limitations beyond the experimental horizon used in the co-culture work. The findings are specific to the organism pair and models studied here, and the abstract does not state whether the results generalize to other microbial communities.
Key points
- P. gingivalis shows Allee-type growth, meaning it needs to pass a quorum threshold to replicate.
- Conditioned medium from V. parvula lowered the quorum threshold for P. gingivalis.
- Microenvironmental noise was modeled as a factor that can support persistence below the Allee barrier.
- Long-term subthreshold experiments were consistent with persistent survival.
- In co-culture, outcomes included rescue for subcritical inocula, coexistence, or P. gingivalis extinction.
Disclosure
- Research title:
- Veillonella can lower the growth barrier for Porphyromonas gingivalis
- Authors:
- Moemen Hussein, Arnab Barua, Mohammad A. Qasaimeh, Matthew Smardz, Patricia I. Diaz, Haralampos Hatzikirou
- Institutions:
- Khalifa University of Science and Technology, Alexandria University, Technische Universität Dresden, New York University Abu Dhabi, New York University, University at Buffalo, State University of New York
- Publication date:
- 2026-02-26
- OpenAlex record:
- View
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