Abstract: The immense diversity of microorganisms in the gut, collectively referred to as intestinal microbiota, forms a complex symbiotic system that both affects and is affected by its host status (Krautkramer et al., 2021; Sommer and Backhed, 2013). Gut microbiota are closely linked to animal health, carrying multiple fundamental functions such as digestion, vitamin production, and the synthesis of other important metabolites and neurotransmitters (Nicolas and Chang, 2019; Wang et al., 2019). A growing body of evidence indicates that microbial metabolites exert direct or indirect regulatory effects on host physiological functions and immune responses to maintain both local and systemic homeostasis (Rooks and Garrett, 2016; Skelly et al., 2019). Recently, Zhang and colleagues used the dextran sulfate sodium-induced colitis model to demonstrate that the commensal bacterium Dubosiella newyorkensis (D. newyorkensis), along with its human counterpart Clostridium innocuum (C. innocuum), mitigates colitis through the production of short-chain fatty acids (propionate in particular) and Lysine (Lys) (Zhang et al., 2024). Lys aids in priming immune tolerance by altering metabolic pathways in dendritic cells, thus establishing an immunosuppressive microenvironment in the colon, thereby offering a potential therapeutic strategy for inflammatory bowel diseases (IBD).