Fig. 6

Antagonistic class II bacteriocins potentially play a regulatory role in the vaginal microbiome. a Correlation network between precursor clusters of class II bacteriocins and bacterial species in the vaginal microbiome. 23 clusters are negatively correlated with species in the community, with spearman’s rho < -0.3 and adjusted P < 0.05 shown in the network. The number in the node denotes the precursor cluster number. Av, Atopobium vaginae; Dm, Dialister micraerophilus; Lc, Lactobacillus crispatus; Li, Lactobacillus iners; Lp, Lactobacillus paragasseri; Vb, Veillonellaceae bacterium DNF00626. b Spearman correlation between precursor clusters and alpha diversity (Shannon index). The dashed line denotes the correlation coefficient cutoff < -0.4 and adjusted P < 0.05. Points refer to 240 precursor clusters detected in the vaginal metagenomes, 21 of which were significantly associated with the alpha diversity of the vaginal microbiome. c Global sequence identity to known class II bacteriocins (upper), sequence length (middle), abundance and prevalence of 21 clusters (bottom) in the vaginal metagenome (MG, n = 169) and metatranscriptome (MT, n = 180). The point size and color are proportionate to the cluster prevalence and average abundance in the MG and MT datasets, respectively. d Gene organization of bgc120802 and precursor sequences of cluster_467 and cluster_468. Putative double-glycines leader peptides are in grey. e The minimum inhibitory concentration (MIC) of chemically synthesized bacteriocins. NA: not available, no inhibitory effect detected with 200 μg/mL. Gram-(-) bacteria, Gram-negative bacteria; Gram-( +) bacteria, Gram-positive bacteria