Table 1.

RNA-dependent DNA synthesis fidelity of WT and mutant RTs in M13mp2 lacZα forward mutation assays.

RTs	Mutant plaques	Total plaques	Mutant frequencya
HIV-1BH10	52	12,836	0.00405
HIV-1ESP49	46	13,347	0.00345 (1.18)
O_K65R	54	18,284	0.00295 (1.37)
O_K65R/V75I	69	23,512	0.00293 (1.38)
MLV	36	13,569	0.00265 (1.53)
AMV	28	11,250	0.00249 (1.63)

For each enzyme, mutant plaques were obtained after transfection of gapped DNA hybridised with the cDNA product of ten synthesis reactions. The RNA used as template in the reverse transcription reaction was synthesized by the T7 RNAP (Promega) in a transcription buffer containing 40 mM Tris-HCl pH 7.9 and 6 mM MgCl₂ (full composition given in Materials and Methods).

^aBackground frequencies in these assays were estimated to be less than one in 20,000 plaques¹⁸. Numbers between parentheses indicate the fold-increase in fidelity relative to the WT HIV-1_BH10 RT.