Kyung-Soo Lee^1,2, Jieun Lee¹, Pureum Lee^1,2, Bong Chan Jeon^2,3, Min Yeong Song^1,2, Sojung Kwak¹, Jungwoon Lee^1,2, Jun-Seob Kim⁴, Doo-Jin Kim⁵, Ji Hyung Kim⁵, Vernon L Tesh⁶, Moo-Seung Lee^1,2,* & Sung-Kyun Park^5,*

¹Environmental Diseases Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon, Korea ²Department of Biomolecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon, Korea ³Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon, Korea ⁴Department of Nano-Bioenginee ring, Incheon National University, Incheon, Korea ⁵Infectious Disease Research Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Daejeon, Korea ⁶Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, TX, USA

^*Corresponding author.

Shiga toxins (Stxs) produced by enterohemorrhagic Escherichia coli (EHEC) are the major virulence factors responsible for hemorrhagic colitis, which can lead to life-threatening systemic complications including acute renal failure (hemolytic uremic syndrome) and neuropathy. Here, we report that O-GlcNAcylation, a type of post-translational modification, was acutely increased upon induction of endoplasmic reticulum (ER) stress in host cells by Stxs. Suppression of the abnormal Stx-mediated increase in O-GlcNAcylation effectively inhibited apoptotic and inflammatory responses in Stx-susceptible cells. The protective effect of O-GlcNAc inhibition for Stx-mediated pathogenic responses was also verified using three-dimensional (3D)-cultured spheroids or organoids mimicking the human kidney. Treatment with an O-GlcNAcylation inhibitor remarkably improved the major disease symptoms and survival rate for mice intraperitoneally injected with a lethal dose of Stx. In conclusion, this study elucidates O-GlcNAcylation-dependent pathogenic mechanisms of Stxs and demonstrates that inhibition of aberrant O-GlcNAcylation is a potential approach to treat Stx-mediated diseases.