Unravelling the unique essential genes ofthrough transposon-directed insertion-site sequencing.

Abstract

represents a major canine pathogen, accounting for 22.4% of streptococcal infections in dogs. However, despite its prevalence in veterinary medicine, the mechanisms underlyingpathogenesis and survival remain poorly understood. Identifying targeted treatments againstcould help to reduce dysbiosis-related complications and minimize the selection of resistant neighbouring bacteria. In this study, we employed transposon-directed insertion-site sequencing for the first time to generate saturated mutant libraries of. By comparing three distinct strains, we defined the shared essential genome of this pathogen. We found that 90.4% of its essential genes are also present in the essential genomes of other related pyogenic streptococcal species, including,andsubsp., demonstrating the translational relevance ofresearch to broader streptococcal biology. Notably, we identified two genes uniquely essential toat the terminal steps of glycolysis:, which governs lactate metabolism, and, which catalyses the conversion of acetyl-CoA to acetyl phosphate in acetate metabolism. We propose that targeting these pathways may offer a novel, species-specific therapeutic strategy for treatinginfections.