A DNA polymerase, required for DNA repair after DNA damage induced by ionizing radiation (IR); this is not the major DNA polymerase (PubMed:19303848). Following severe irradiation (7 kGy of gamma irradiation) genomic DNA is fragmented. DNA is progressively degraded for the first 1.5 hours after IR, in a step promoted by RecA and counterbalanced by DNA Pol I and Pol III, followed by massive DNA synthesis and genome reassembly in the next hour. Optimal priming of DNA synthesis requires both RecA and RadA, Pol III initiates DNA synthesis while both Pol I and Pol III are required for its contination (PubMed:19303848). May also have 5'-3' exonuclease activity (By similarity). a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) Single-chain monomer with multiple functions. Increased sensitivity to ionizing radiation (IR), lag time before DNA synthesis/repair commences increases considerably, decreased rates of both DNA synthesis and DNA repair following IR. If combined with a temperature-senstitive mutation in dnaE (catalytic subunit of Pol III) viability at 37 degrees is dramatically reduced (PubMed:19303848). Belongs to the DNA polymerase type-A family.