S. auricularis ABE8e Adenine Base Editor

Compact adenine base editor using S. auricularis Cas9, providing alternative PAM specificity for expanded targeting.

Length: 3900 bp (1300 aa)

Type: Adenine Base Editor

Conversion: A-to-G

Origin: TadA8e deaminase fused to Staphylococcus auricularis SauriCas9 D10A nickase

Characteristics

Compact architecture using SauriCas9 (similar size to SaCas9) enables single-AAV delivery. Uses 21-nucleotide protospacer. Editing window spans positions 4-9. Alternative PAM specificity complements SaCas9 and other compact editors. Part of three-editor suite collectively targeting ~82% of genomic adenines. Compatible with SaCas9 sgRNA scaffolds.

Applications

Single-AAV base editing at sites inaccessible to SaCas9, Nme2Cas9, and CjCas9 PAM requirements. Complementary to other compact editors for comprehensive genome coverage. Enables multi-editor therapeutic strategies where different PAM specificities are required for targeting multiple loci.

Limitations

Specific PAM requirements limit individual targeting scope. Less characterized than SaCas9-based editors. May require optimization of guide design and delivery parameters for specific applications.

Literature References

  1. Gaudelli NM, Komor AC, Rees HA, et al. (2017). Programmable base editing of A•T to G•C in genomic DNA without DNA cleavage. Nature 551:464-471 - Gaudelli 2017 Adenine Base Editor
  2. Richter et al. (2020). Phage-assisted evolution of an adenine base editor with improved Cas domain compatibility and activity. Nat Biotechnol - Richter 2020 ABE8e
  3. Davis et al. (2022). Efficient in vivo base editing via single adeno-associated viruses with size-optimized genomes encoding compact adenine base editors. Nat Biomed Eng - Davis 2022 Single-AAV ABEs
  4. Yang et al. (2024). Adenine base editor-based correction of the cardiac pathogenic Lmna c.1621C > T mutation in murine hearts. J Cell Mol Med - Yang 2024 SauriABE8e