(A) The lesion recognition complex of hOGG1 bound to DNA with the oxoG base inserted in the active site (PDB ID: 1YQR, [17]), (B) specific contacts of enzyme with the cytosine which is located opposite to oxoG base (PDB ID: 1EBM, [9]), (C) the complex of hOGG1 bound to the DNA with the G base inserted in the exo-site (PDB ID: 1YQK, [17]), (D) the complex of hOGG1 bound to the DNA, with the G base inserted in the active site (PDB ID: 3IH7, [19]). The overlays of the trapped catalytic complex hOGG1/oxoG-substrate (red, 1HU0, [16]) with either (E) the complex of hOGG1 bound to DNA with the G base inserted in the exo-site (blue, 1YQK, [17]) or (F) the complex of hOGG1 bound to DNA, with the G base inserted in the active site (green, 3IH7, [19]).