Exploring compositional and predicted functional alterations of gut microbiota in H. pylori infection

Abstract

Abstract H. pylori infection is prevalent worldwide having detrimental effects on the gastrointestinal tract. H. pylori has been linked to compositional variations in gastric microbiota, with insufficient knowledge on extended effect to intestinal microbiota. Moreover, functional potentials of gut microbiota remain underexplored. Aim We sought to investigate the compositional and functional shifts in gut microbiota associated with H. pylori infection. Total 54 stool samples were obtained from H. pylori infected patients tested positive for stool antigen (n = 31) compared to control group (n = 23). All samples were subjected to 16SrRNA next-generation sequencing. By comparison with the control group, the H. pylori-positive group displayed relatively higher mean relative abundance (RA) of phyla of Bacteroidetes (43.59%) and Proteobacteria (8.36%), mainly genera of Bacteroides (22.5%) and Prevotella (13.48%) and species of Bacteroides vulgatus (7%) and E. coli (4%). Other low abundant clinically relevant taxa were more enriched in H. pylori-positive group than controls such as Desulfovibrio, Enterococcaceae, Rikenellacae, and Akkermansia. H. pylori-positive group showed distinctive representaion of Prevotella species (PAC001042_s), Citrobacter and Howardella,, while Blautia genus was exclusively identified in the control group. Both study groups showed comparable microbiota diversities with no significant difference. H. pylori-positive group revealed higher abundance of MAPK signaling functional pathways (FDR = 0.046), along with Cell cycle and Ariginine and proloine pathways (FDR = 0.05) compared to the controls. Our findings inferred compositional and functional alterations in H. pylori-associated gut microbiota that may play role in gut inflammation and malignant transformation observed in H. pylori infection.