Fig. 3.

Initiation of sporulation. During the limited nutrient availability, the sensor kinases (KinA-KinE) initate Spo0F through prohpshorylation. The PAS domain of KinA initiate sporulation which are thought to activate by sensing energy potential or redox state and the repression of kinB transcription by the activity of CodY repressor as it binds to GTP. Phosphorylated Spo0F pass on its phosphate group to Spo0B and subsequently shift the phosphate group to Spo0A, triggering transcriptional regulatory mechanism that leads to sporulation. During DNA damage or impaired DNA replication, sda is activated to prevent sporulation process. Spo0E can dephosphorylate Spo0A. Spo0àP represses transcription of abrB gene to initiate transcription of sporulation genes, for more detail of this process refer to Ref. [60].