Engineering a bacterial toxin deaminase from the DYW-family into a novel cytosine base editor for plants and mammalian cells

authored by

Dingbo Zhang, Fiona Parth, Laura Matos da Silva, Teng-Cheong Ha, Axel Schambach, Jens Boch

Abstract

Base editors are precise editing tools that employ deaminases to modify target DNA bases. The DYW-family of cytosine deaminases is structurally and phylogenetically distinct and might be harnessed for genome editing tools. We report a novel CRISPR/Cas9-cytosine base editor using SsdA, a DYW-like deaminase and bacterial toxin. A G103S mutation in SsdA enhances C-to-T editing efficiency while reducing its toxicity. Truncations result in an extraordinarily small enzyme. The SsdA-base editor efficiently converts C-to-T in rice and barley protoplasts and induces mutations in rice plants and mammalian cells. The engineered SsdA is a highly efficient genome editing tool.

Organisation(s)

Section Plant Biotechnology
Institute of Plant Genetics

External Organisation(s)

University of Science and Technology Beijing
Hannover Medical School (MHH)
REBIRTH Research Center for Translational Regenerative Medicine
Harvard Medical School (HMS)

Type

Article

Journal

Genome biology

Volume

2025

ISSN

1474-760X

Publication date

03.02.2025

Publication status

Published

Peer reviewed

Yes

Electronic version(s)

https://doi.org/10.1186/s13059-025-03478-w (Access: Open)