Nucleases

CRISPR nucleases are the programmable DNA-cutting enzymes that enable genome editing. Size determines AAV compatibility, PAM sequence defines targetable sites, and origin species affects immunogenicity. Compare compact variants like CasMINI (1.6 kb) against standard SpCas9 (4.1 kb) to select the right nuclease for your delivery constraints and targeting requirements.

NameSize (kb)PAMOrigin
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)
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)