Replication of the genome is one of the most fundamental of biological activities, hence the interest in the mechanism by which the enzymes concerned -- the polynucleotide polymerases -- carry out the process. The co-crystal structures of the DNA polymerase that replicates bacteriophage T7, and of theBacillus stearothermophilusDNA polymerase large fragment, provide significant insights into the catalytic mechanism, fidelity and processivity of DNA polymerases.
