Plays an important role in radiation resistance and DNA double-strand break (DSB) repair. Involved in transcriptional regulation of genes important for bacterial stress response. Phosphorylates PprA in vitro. ATP + L-seryl-[protein] = ADP + H(+) + O-phospho-L-seryl-[protein] ATP + L-threonyl-[protein] = ADP + H(+) + O-phospho-L-threonyl-[protein] Autokinase activity is stimulated by DNA damage. Stimulated by PQQ and DNA ends in vitro. Expression is induced in response to DNA damage. Contains an N-terminal catalytic kinase domain and a C-terminal PQQ binding domain. Autophosphorylated. Mutant exhibits higher sensitivity to different DNA-damaging agents. It shows altered phosphoprotein profile and impaired DSB repair. Deletion affects expression of genes involved in intermediary metabolism, stress response and growth under stressed conditions. Belongs to the protein kinase superfamily. Ser/Thr protein kinase family.