Biomolecular condensates in spatiotemporal regulation of the bacterial cell division cycle.

Bacteria lack membrane-bound organelles, yet they achieve chromosome replication, segregation, and cell division with remarkable spatial and temporal precision. Recent work shows that biomolecular condensates formed by liquid-liquid phase separation play a central role in this organization. In the crowded bacterial cytoplasm, multivalent proteins and nucleic acids form dynamic condensates that concentrate factors, tune reaction kinetics, and create distinct microenvironments. Here we focus on phase separation by cell division proteins, including the divisome scaffold FtsZ and regulators operating in different species. We discuss the factors that control the biomolecular condensation of these proteins and the key role of phase separation in orchestrating the bacterial cell division cycle, with implications for synthetic cell design and antibiotic development.