HP and infection: Among them, fifteen sharing differential OTUs were considered to be CAG-related bacteria independent of Hp-infection, and they belonged to phylum Proteobacteria, including genus Labrys, Rhodopseudomonas, Pseudolabrys, Methylobacterium, Acidovorax, Bradyrhizobium, Variovorax, Pelomonas, and Herbaspirillum (Figure 3B).