Carbon metabolism shapes FtsZ levels and cell division in the cyanobacterium Anabaena PCC 7120.

Cyanobacteria, as photoautotrophs, play key ecological roles and are widely used in synthetic biology research. While metabolism profoundly influences cellular processes like cell division, the regulatory mechanisms linking these activities remain poorly understood in cyanobacteria. Here, we perturb the tricarboxylic acid (TCA) pathway by introducing an extra CO2 fixation module in the model cyanobacterium Anabaena sp. PCC 7120. This modification alters the levels of the cell division protein FtsZ, impairing cell division under varying light conditions. We found that 2-oxoglutarate, an intermediate of the TCA pathway known as a metabolic signal, regulates ftsZ expression via the transcription factor NtcA. Furthermore, metabolic status modulates cell division in a NtcA-dependent manner, directly integrating metabolic control and cell division. Our findings uncover a coordination mechanism between metabolism and cell division in cyanobacteria, providing mechanistic insights for synthetic biology engineering and understanding of metabolic regulation.