Table 2.
DNA-catalyzed cleavage of HIV-1 mRNA substrates under simulated physiological conditions
| Target | Substrate | Arm length | kcat, min−1 | Km, nM |
|---|---|---|---|---|
| gag/pol | (G)GAGAGAGA·UGGGUGC(G) | 7 + 7 | 0.1 | 0.9 |
| 8 + 8 | 0.1 | 0.7 | ||
| env | (C)AGUGGCAA·UGAGAGU(G) | 7 + 7 | 0.03 | 900 |
| 8 + 8 | 0.04 | 9 | ||
| vpr | (G)AGGAUAGA·UGGAACA(A) | 7 + 7 | 0.08 | 500 |
| 8 + 8 | 0.1 | 20 | ||
| tat | GCAAGAAA·UGGAGCC | 7 + 7 | 0.04 | 300 |
| nef | CUAUAAGA·UGGGUGA | 7 + 7 | 0.05 | 900 |
Kinetic values were obtained under multiple turnover conditions, with synthetic RNA substrate in >10-fold excess over synthetic DNA enzyme. Reaction conditions: 2 mM MgCl2 and 150 mM NaCl (pH 7.5), 37°C. Substrate sequences correspond to 15 or 17 nt surrounding various mRNA start codons (underlines) of the BH10 clone of HIV-1 (17).