Fig. 3

The gut microbial compositions for CN− and CN+ participants. A The bacterial community in both groups at different taxonomic levels. Bar graphs indicated the relative abundance of phylum-level, class-level, order-level, and family-level taxa. B LEfSe analysis between CN− and CN+. As shown in the histogram of LDA scores for differentially abundant taxa, positive LDA scores indicated the enrichment of taxa in the CN+ group (green), and negative LDA scores indicated the enriched taxa in the CN− group (red). The LDA scores (log10) > 2 and p < 0.05 were listed. Cladogram indicated the phylogenetic distribution of gut bacteria. Colors represented different groups (CN−, red; CN+, green). Nodes with different colors represented important taxa in different groups. Yellow nodes suggested no significantly differential taxa between the two groups. C The heatmap showing the relative abundance and distribution of differentially abundant taxa identified by the LEfSe method. CN− amyloid-β-negative cognitively normal participants, CN+ amyloid-β-positive cognitively normal participants, LEfSe linear discriminant analysis (LDA) effect size