Multicellular dynamics and wealth distribution in bacteria

Abstract

In a variety of infections, bacteria form multicellular communities which contribute to virulence and antibiotic tolerance. The molecular biology of such communities is actively studied, but our understanding of them remains incomplete. In this issue, Şimşek et al have developed and experimentally validated a dynamic model for community formation and revealed general insights into bacterial collective survival during antibiotic exposure.

Figure 1. Collective survival of bacterial communities.

(Left) Antibiotic exposure kills individual cells which lack antibiotic resistance genes. However, in multicellular communities (including patches, aggregates, biofilms, etc) beneficial interactions can enable the same bacteria to thrive. Different species can employ a variety of molecular mechanisms to produce such collective survival. Using dynamic modeling, Şimşek et al show that local collective survival enables multicellular communities “rich” in beneficial interactions to grow “richer,” thereby accounting for “patchiness,” i.e., the spatial distribution in community size. Their study indicates that the dynamics of multicellular survival may be general, despite the underlying molecular mechanisms being diverse, and provides a straightforward model for contextualizing molecular-scale insights. (Right) Multicellular communities play critical roles in variety of bacterial infections, including driving virulence and antibiotic tolerance. Deciphering these roles will advance our approaches to infectious diseases, and will require dynamic models (like Şimşek et al’s), molecular insights, and direct observations of bacterial behavior. Without any one of these pieces, the picture will remain incomplete. Source data are available online for this figure.