Table 2A. Error rates of Tgo-Pol (exo⁻) and Tgo-Pol Z1 (exo⁻) determined using pSJ2^a or pSJ3^a (a plasmid-based fidelity assay employing the lacZα indicator gene).

Protein	Total number of coloniesb	Number of white (mutant) colonies	Corrected mutation frequencyc	Error rated
Tgo-Pol (exo+)	29 271	20	5.7 × 10−4	2.8 × 10−6
Tgo-Pol (exo−: D215A)	62 656	155	2.4 × 10−3	1.2 × 10−5
Z1-Tgo-Pol (exo−: D215A)	64 657	266	4.0 × 10−3	1.9 × 10−5
Pfu-Pol (exo−: E143A/D215A)(D473G)e	78 431	296	3.7 × 10−3	1.8 × 10−5
Eco-Pol II (exo+)	59 235	28	4.4 × 10−4	3.0 × 10−6
Eco-Pol II (exo−: D335N)	41 903	128	3.0 × 10−3	2.1 × 10−5

^apSJ2 was used with the archaeal enzymes, pSJ3 with E. coli DNA polymerase II.

^bThe fidelity of each protein was determined in three separate experiments, each of which involved scoring E. coli colonies on five separate plates. The aggregated numbers are given.

^cCorrected mutation frequency equals: ({number of white colonies/total number of colonies} – background mutation rate). Background mutation rates of 1.1 × 10⁻⁴ and 3.1 × 10⁻⁵ were used for gapped pSJ2 and pSJ3, respectively (36).

^dError rate is the number of mistakes made per base incorporated. The corrected mutation frequency was converted to the error rate as previously described.

^eData taken from an earlier publication (36).