Participates in a DNA-damage check-point that is active prior to asymmetric division when DNA is damaged. DisA forms globular foci that rapidly scan along the chromosomes during sporulation, searching for lesions. When a lesion is present, DisA pauses at the lesion site. This triggers a cellular response that culminates in a temporary block in sporulation initiation. Has also diadenylate cyclase activity, catalyzing the condensation of 2 ATP molecules into cyclic di-AMP (c-di-AMP). c-di-AMP acts as a signaling molecule that couples DNA integrity with progression of sporulation. The rise in c-di-AMP level generated by DisA while scanning the chromosome, operates as a positive signal that advances sporulation; upon encountering a lesion, the DisA focus arrests at the damaged site and halts c-di-AMP synthesis. 2 ATP = 3',3'-c-di-AMP + 2 diphosphate Diadenylate cyclase activity is inhibited by the interaction with RadA. Homooctamer (By similarity). Interacts with RadA. Belongs to the DisA family.