Nucleases
Programmable nucleases are enzymes engineered to cut DNA at specific sequences, enabling targeted genome modification. Selection depends on the length of DNA recognition sequence, cutting mechanism (blunt vs. staggered ends), size constraints for delivery vehicles, and compatibility with different guide RNA architectures.
| Name | Size (kb) | PAM | Origin |
|---|---|---|---|
| Al3Cas12f | — | TTTV |
Alistipes sp. |
| Al3Cas12f RKK | — | TTTV |
Alistipes sp. (engineered) |
| Cas12a | — | TTTV |
Lachnospiraceae bacterium (Lb) |
| Cas12f | — | TTTV or TTV |
Uncultivated archaea |
| Cas13a RNA-Targeting | — | H (protospacer flanking site on RNA) |
Leptotrichia shahii |
| Cas9 D10A Nickase | — | NGG |
Streptococcus pyogenes (engineered) |
| CasMINI | — | TTTV |
Uncultivated archaea (Un1Cas12f1) |
| dCas9 Catalytically Dead | — | NGG (binds but does not cut) |
Streptococcus pyogenes (engineered) |
| enAsCas12a | — | TTTV |
Acidaminococcus sp. (engineered) |
| eSpCas9 | — | NGG |
Streptococcus pyogenes (engineered) |
| hfCas12Max | — | TN or TTN |
Cas12i (engineered via directed evolution) |
| impLbCas12a | — | — |
— |
| LbCas12a-RVRR | — | — |
— |
| NmeCas9 | — | NNNNCC |
Neisseria meningitidis |
| OpenCRISPR-1 | — | NGG |
AI-generated (Profluent Bio) |
| OsCas12f | — | YTTH |
Oscillibacter sp. |
| RhCas12f | — | NCCD |
Ruminiclostridium herbifermentans |
| SaCas9 | — | NNGRRT |
Staphylococcus aureus |
| SpCas9 | — | NGG |
Streptococcus pyogenes |
| SpCas9-HF1 | — | NGG |
Streptococcus pyogenes (engineered) |
| St1Cas9 | — | NNAGAAW |
Streptococcus thermophilus (CRISPR1) |
| xCas9 | — | NG, GAA, GAT |
Streptococcus pyogenes (engineered) |