Corynebacterium glutamicum S9114, a superior strain widely used in glutamic acid industrial production through traditional mutagenesis screening, is highly suitable as a "cell factory" for producing other glutamine derivatives (e.g., N-acetylglucosamine, GlcNAc). However, its "non-model" characteristics limit the efficiency and adaptability of existing universal editing tools like CRISPR-Cas9, restricting precise metabolic engineering modifications.
The research team developed an innovative gene-editing platform by synergistically integrating the CRISPR-Cpf1 system with a screened endogenous recombinase, CauR. Through systematic optimization, the platform achieved a gene knockout efficiency of up to 77% in the S9114 strain.
Researchers systematically redesigned the metabolic network of S9114 by knocking out multiple genes in competing metabolic pathways to minimize carbon flux losses, while enhancing key steps in the GlcNAc synthesis pathway to boost precursor supply. The engineered strain ultimately achieved high-efficiency overproduction of GlcNAc in a fermenter, yielding 141.2 g/L with a production intensity of 1.88 g/(L·h), demonstrating the platform's exceptional capability in constructing high-efficiency microbial cell factories.
The work entitled " Development of a CRISPR-Cpf1 and endogenous recombinase synergy platform for N-acetylglucosamine overproduction in Corynebacterium glutamicum S9114 " was published on Systems Microbiology and Biomanufacturing (published on November 25, 2025).
