Fig. 5

Integrated association of the differential gut microbial features with fecal metabolites, CCHD-P versus CCHD-G. A, B Overview of the significant associations between multilevel microbial features and fecal metabolites. The significant associations between continuous microbial variables (microbial abundance, metabolic pathways, and vSVs) and fecal metabolites are determined by Spearman’s rank correlation analysis and shown in Circos plot A; whereas the significant associations between binary microbial variables (dSVs) and fecal metabolites are determined by Mann–Whitney U test and shown in heatmap B. The associated microbial features and metabolites are identified in the comparison of CCHD-P and CCHD-G. Other metabolites include lipids, amino acids, nucleotides, and carbohydrates. C Heatmap of significant correlations between fecal metabolites (including LA derivatives, B vitamins, and aromatic lactic acids) with Enterococcus abundance and vSVs in Enterococcus faecalis ATCC29212 (Spearman’s rank correlation analysis). Asterisks indicate statistical significance. D Boxplots (center, median; box, IQR; whiskers, IQR × 1.5; dots, outliers) showing the relative abundance of pyridoxal in individuals harboring a 9-kbp dSV in Enterococcus faecium NRRL B.2354 genome (blue, n = 23) and individuals with no deletion (red, n = 13). Significance is determined by Mann–Whitney U test. *P < 0.05, **P < 0.01. CCHD-G, CCHD patients with good prognosis; CCHD-P, CCHD patients with poor prognosis; HMOs, human milk oligosaccharides; SCFAs, short-chain fatty acids; LA, linoleic acid; dSV, deletion structural variation; vSV, variable structural variation