Single-cell analysis and control of microbial systems using optogenetics.

Single-cell resolution studies have transformed our understanding of microbial systems, revealing substantial cell-to-cell heterogeneity and complex dynamic behaviors. This review describes recent advances in using optogenetics, where light-sensitive proteins control cellular processes, to investigate microbial behavior at the individual cell level. We discuss studies where optogenetic approaches have enabled high-resolution analysis of properties such as relative cell positioning, subcellular localization, morphology, and gene expression dynamics. In addition, we highlight emerging feedback and event-driven control methods that dynamically modulate cellular states using light signals. By leveraging light's unique capabilities for spatial and temporal manipulation, researchers can now probe cellular characteristics with unprecedented precision. We anticipate significant advances as researchers introduce more sophisticated dynamically patterned light signals for single-cell microbial research.