Gut Microbiome Profiles in CB2R-Knockout and Wild-Type Mice With and Without Salmonella Infection

This dataset examines how genetic deletion of cannabinoid receptor 2 (CB2R) impacts gut microbiome composition during Salmonella enterica serovar Typhimurium infection. CB2R is a G protein-coupled receptor involved in regulating immune responses and intestinal homeostasis. Its expression in immune cells and the gastrointestinal tract suggests a potential role in shaping host-microbiota interactions. To investigate whether CB2R deficiency alters microbial dynamics in a way that influences susceptibility to infection, we compared CB2R knockout (CB2R-KO) mice with wild-type (WT) littermate controls in an oral Salmonella challenge model. Fecal samples were collected at two time points: pre-infection (baseline) and four days post-infection. Samples were subjected to shallow shotgun metagenomic sequencing (1×150 bp, Illumina). Raw reads were filtered using Vsearch to remove low-quality sequences and short fragments. Taxonomic classification was performed with Kraken2, and processed data were analyzed using R (phyloseq, ALDEx2, microbiome packages). Alpha diversity analysis showed no significant difference in species richness or evenness between genotypes. However, CB2R-KO mice exhibited distinct shifts in microbial composition following infection. These findings suggest that CB2R contributes to maintaining a balanced gut microbial ecosystem and that its absence may promote dysbiosis during enteric infection, potentially increasing host susceptibility.