FIGURE 2.

Unsupervised spectral clustering of the sputum metagenome in bronchiectasis reveals three clusters with pan-European distribution. a) Principal coordinate analysis (PCoA) plot, based on Bray–Curtis dissimilarity, illustrating three microbiome clusters: Pseudomonas-dominant (n=71; green), Streptococcus-dominant (n=224; orange) and Haemophilus-dominant (n=54; purple). Circles intersected by a cross indicate PCoA centroids of the identified clusters. p-value determined by PERMANOVA.

b) Stacked bar plots illustrating microbiome composition of the three clusters. c) Linear discriminant analysis (LDA) effect size analysis illustrating the top 20 differentially abundant microbial species across the identified clusters. d) Differences in α-diversity (Shannon diversity index) of the lung microbiome across the identified clusters. Data presented as median and interquartile ranges, with whiskers indicating range. e) Distribution of the identified clusters across the respective regions in Northern and Western Europe (NWE) (n=39), Southern Europe (SE) (n=174) and the UK (n=136). ns: nonsignificant; PC: principal coordinate. ***: p<0.001.