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bioRxiv · 10.1101/582403

CRISPR-BEST: a highly efficient DSB-free base editor for filamentous actinomycetes

Tong, Y.·Robertsen, H. L.·Blin, K.·Klitgaard, A. K.·Weber, T.·Lee, S. Y.
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Abstract

Filamentous actinomycetes serve as major producers of various natural products including antimicrobial compounds. Although CRISPR-Cas9 systems have been developed for more robust genetic manipulations, concerns of genome instability caused by the DNA double-strand breaks (DSB) and the toxicity of Cas9 remain. To overcome these limitations, here we report development of the DSB-free, single-nucleotide resolution genome editing system CRISPR-BEST (CRISPR-Base Editing SysTem). Specifically targeted by an sgRNA, the cytidine deaminase component of CRISPR-BEST efficiently converts C:G to T:A within a window of approximately seven-nucleotides. The system was validated and successfully used in different Streptomyces species.

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Tong, Y., Robertsen, H. L., Blin, K., Klitgaard, A. K., Weber, T., Lee, S. Y.. 2019-03-20. CRISPR-BEST: a highly efficient DSB-free base editor for filamentous actinomycetes. https://doi.org/10.1101/582403

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