ABE-MG34-1

ABE-MG34-1 is an adenine base editor (ABE) research tool designed for precise genome editing. It is a fusion protein comprising a compact Cas9 nickase, Cas9d-MG34-1, and an evolved TadA*(8.8 m) deaminase. The Cas9d-MG34-1 component is a type II-D Cas9 ortholog derived from Deltaproteobacteria and is notably small, consisting of only 747 amino acids. This compact size allows the entire ABE-MG34-1 expression cassette to remain under 3.4 kb, which facilitates efficient delivery via a single adeno-associated virus (AAV) vector—a significant advantage over larger CRISPR systems that often require dual-vector delivery. ABE-MG34-1 has demonstrated the ability to perform targeted A-to-G base conversions at multiple genomic loci in both bacterial (E. coli) and human (HEK293T) cells, making it a versatile platform for gene therapy research.