In contrast, some G− taxa, such as Bacteroides, Blautia, Escherichia coli, Shigella, Chlamydia, and Fusobacterium, are closely and positively correlated with AD, mainly involving the activation of systematic inflammation by their enriched LPS in the cell wall and the invasion of proinflammatory cytokines, LPS, and even bacteria into the blood circulation system and brain, inducing Aβ deposition and tau phosphorylation [15–17, 70]. The gene discussed is MAPT; the disease is Alzheimer disease.