Protein–Nucleic Acid Interactions 411
Figure 10.17 Representative bacterial DNA polymerases. (a) T7 bacteriophage DNA polymerase with duplex
DNA (black) (PDB: 1T7P). Conformational changes are necessary to adapt the protein to the DNA
substrate. (b) Thermophilic polymerase (PDB: 1QHT). Here, the polymerase adopts a more
compact structure in the absence of DNA. Note the domain organization, with segments labeled
‘thumb’, ‘palm’ and ‘fingers’ according to polymerase nomenclature. The 3–5exonuclease domain
is coloured red