AP endonucleases, AP site, click chemistry, DNA glycosylases, DNA polymerases, DNA repair, translesion synthesis, DNA-(Apurinic or Apyrimidinic Site) Lyase/metabolism, DNA-Directed DNA Polymerase/metabolism, Humans, Escherichia coli/metabolism, DNA Polymerase I/genetics, DNA Repair, DNA Damage, Endonucleases/metabolism