SepT, a novel protein specific to multicellular cyanobacteria, influences peptidoglycan growth and septal nanopore formation in sp. PCC 7120.

Multicellular organization is a requirement for the development of complex organisms, and filamentous cyanobacteria such as represent a paradigmatic case of bacterial multicellularity. The filament can include hundreds of communicated cells that exchange nutrients and regulators and, depending on environmental conditions, can include different cell types specialized in distinct biological functions. Hence, the specific features of the filament and how they are propagated during cell division represent outstanding biological issues. Here, we studied SepT, a novel coiled-coil-rich protein of that is located in the intercellular septa and influences the formation of the septal specialized structures that allow communication between neighboring cells along the filament, a fundamental trait for the performance of as a multicellular organism.