[P006] Poster

1:00 PM - 1:50 PM JST(4:00 AM - 4:50 AM UTC)

[P03-304] Genome-wide CRISPRi screens in Eubacterium limosum elucidates essential genes and enhanced autotrophic phenotypes

○Chanho Park¹, Jongoh Shin¹, Jiyun Bae¹, Seulgi Kang¹, Dongwhi Lee¹, Hyunwoo Jung², Minkyu Huh², Jejin Kim², Minkoo Jung², Suhyung Cho^1,3, Byung-Kwan Cho^1,2,3 (1. Department of Biological Sciences, Korea Advanced Institute of Science and Technology (Korea), 2. Graduate School of Engineering Biology, Korea Advanced Institute of Science and Technology (Korea), 3. KI for the BioCentury, Korea Advanced Institute of Science and Technology (Korea))

Keywords:

Acetogenic bacteria,CRISPRi,Genome-wide screening

Acetogenic bacteria are promising biocatalysts for sustainable bioconversion of carbon oxides (e.g., CO and CO₂) into multi-carbon biochemicals. Genotype-phenotype relationships are important for engineering their metabolic capability to enhance biocatalytic performances; however, systemic elucidations on the fitness contribution of individual genes has been limited. Here, we performed a genome-scale CRISPR interference (CRISPRi) screen using 41,939 guide RNAs designed from the genome of Eubacterium limosum, a model acetogenic species, for transcriptional repression of all genes. Our data revealed the gene essentiality of E. limosum, where the Wood-Ljungdahl pathway and membrane regeneration are essential for its autotrophic growth. Furthermore, we discovered genes that increased autotrophic growth rates 4-fold and acetoin production 1.5-fold compared to the wild-type under CO₂-H₂ conditions. These results provide insight for understanding and engineering of acetogenic bacteria.
This work was supported by Korea Environmental Industry & Technology Institute (KEITI) through Technology Development Program for CO₂ Mitigation and Conversion to Value-Added Products Using Indigenous Organism, funded by Korea Ministry of Climate, Energy and Environment (MCEE) (RS-2026-25505528).