Table II.
Effects of Different Parameters on Phosphorothioate Primer Cloninga
| Modification of PCR fragments | Combination of DNA | Exonuclease treatment | Number of recombinants |
|---|---|---|---|
| 5′ P + phosphorothioate | Vector + insert | + | 82 |
| 5′ P + phosphorothioate | Vector + insert | − | 0 |
| 5′ P − phosphorothioate | Vector + insert | + | 0 |
| 5′ OH + phosphorothioate | Vector + insert | + | 2 |
| 5′ OH − phosphorothioate | Vector + insert | + | 0 |
| 5′ P + phosphorothioate | Vector | + | 4 |
| 5′ P + phosphorothioate | Vector | − | 0 |
| 5′ P + phosphorothioate | Insert | + | 0 |
| 5′ P + phosphorothioate | Insert | − | 0 |
a
Mixtures of equimolar PCR fragments (10 ng pUC18 and 4 ng ape_0119) or respective target/vector fragments were incubated with λ exnuclease (250 ng exonuclease/pmol DNA) at 37°C for 5 min before transforming into E. coli.