Table 1.
Specific polymerization activities and AZT resistance of SFVmac PR-RTs and corresponding viruses
| Enzyme | 1 SPAC | p-value | 2 AZTMP excision (%) | 3 Viral titer in % | |
|---|---|---|---|---|---|
| w/o AZT | 5 μM AZT | ||||
| WT | 28.6 (±3.1) | - | 3.0 (±1.1) | 100 | <0.1 |
| K211I | 7.0 (±4.8) | 0.005 | 2.4 (±1.4) | 1.2 (±1.2) | <0.1 |
| I224T | 22.5 (±10.3) | 0.410 | 3.5 (±1.4) | 146.5 (±21.4) | 0.1 |
| S345T | 28.8 (±8.3) | 0.977 | 10.4 (±1.2) | 40.0 (±16.8) | 1.1 (±1.0) |
| E350K | 44.7 (±2.1) | 0.003 | 2.8 (±0.7) | 31.7 (±8.8) | <0.1 |
| mt2a | 13.3 (±0.9) | 0.009 | 14.5 (±0.7) | <0.1 | <0.1 |
| mt2b | 8.7 (±2.9) | 0.001 | 7.9 (±0.6) | 23.0 (±7.9) | <0.1 |
| mt2c | 32.6 (±13.8) | 0.667 | 18.7 (±1.2) | 20.6 (±5.5) | 3.0 (±2.1) |
| mt3 | 15.5 (±2.6) | 0.005 | 35.4 (±0.6) | 8.6 (±2.7) | 2.8 (±1.3) |
| mt4 | 21.7 (±3.9) | 0.079 | 37.9 (±1.3) | 113.0 (±19.2) | 68.8 (±18.8) |
1SPAC, specific activity in U/10 min*μgprotein. One Unit (U) catalyzes the incorporation of 1 nmol TTP in a poly(rA)/oligo(dT)15 in 10 min at 37°C by 1 μg PR-RT. The values are the means and standard deviations of at least three independent experiments. The p-values were calculated using the unpaired t-test in which we compared each variant with the WT. p-values ≤0.05 are considered significant. 2Quantification of AZTMP removal depicted in Figure 2C was achieved by phosphoimaging. The amount of unblocked primer after AZTMP excision (P30) is equivalent to the quantity of excised AZTMP and is given as a percentage of the total amount of primer in the reaction. 3Data taken from [11]. The viral titers in the cell free supernatants of the WT in the absence of AZT were set to 100% (≙ viral titer of 7 x 104). Titers of mutant viruses are expressed relative to the WT. Standard errors are given in parenthesis.