Unlocking the bacterial condensome: from 'dark matter' to design.

Biomolecular condensates have transformed our understanding of eukaryotic cellular organization, yet their roles in bacteria remain comparatively underexplored. This gap arises from the physical constraints of bacterial cell size, the diversity of molecular mechanisms that drive condensation, and the limited representation of bacterial condensates in current predictive frameworks. Here, we argue that condensation is a widespread but underrecognized principle of bacterial intracellular organization. We describe how scaffold architecture, multivalent interactions, and non-equilibrium regulation collectively determine condensate material states and cellular function. Using bacterial microcompartments as a case study, we show how diverse condensation mechanisms can converge to organize functional organelles. We further highlight emerging computational, imaging, and perturbation-based approaches that are shifting the field from condensate identification toward mechanistic understanding and predictive design. By uncovering the physical principles governing bacterial condensates, we envision their use as programmable biomaterials whose properties can be engineered to control cellular function and enable synthetic organelles.