For 10 points, name this family of enzymes that aids in
 DNA replication by pairing the template strand's nucleotides to free nucleotides, one of which from 

One of these enzymes associates with a donut-shaped dimer known as the sliding clamp, made up of
 two beta subunits of its holoenzyme. Another of these enzymes, when cleaved by subtilisin, produces a
 C-terminal fragment known as the Klenow fragment. Arthur Kornberg discovered the first of these
 enzymes used in Sanger sequencing. The synthesis of two "bypass" ones is induced by the SOS response,
 and one of those forms a namesake mutasome that incorrectly adds guanine opposite a thymine residue
 about half as often as it correctly adds adenine. For 10 points, name this family of enzymes that aids in
 DNA replication by pairing the template strand's nucleotides to free nucleotides, one of which from 
Thermus aquaticus is used in PCR.
One of these enzymes associates with a donut-shaped dimer known as the sliding clamp, made up of
 two beta subunits of its holoenzyme.
DNA {polymerase} [or {Pol} ; prompt on {polymerase} ]