Garvicin Q-producing Lactococcus garvieae LG3092: its role in mitigating dysbiosis and H. pylori-associated gastritis

H. pylori induces gastritis and promotes gastric carcinogenesis. Antimicrobial therapy against H. pylori often causes gastrointestinal dysbiosis, with side effects like vomiting, diarrhea, and antibiotic resistance, hindering effective eradication. This study investigated the effects and mechanisms of probiotics in balancing microbiota to alleviate H. pylori-related gastritis. Using in vivo and in vitro gastritis models with various H. pylori virulence strains, the study employed 16S rRNA amplicon sequencing and qPCR to link gastric microbiota with inflammation. Genomic mining and microbiota reconstruction identified Lactococcus garvieae LG3092 and GarQ as key microecological-targeting regulators. Results showed that different H. pylori induce varying levels of gastritis in vivo, with elevated IL-1β, IL-6, and TNF-α levels linked to pro-inflammatory bacteria. LG3092 secretes GarQ, specifically targeting Man-PTS receptors on pro-inflammatory bacteria, disrupting their membranes and modulating the gastric microbiota, highlighting the potential of probiotics in combination with other therapies to managing H. pylori infection and related gastritis.