Fig. 1
From: Host adaptation in gut Firmicutes is associated with sporulation loss and altered transmission cycle
Sporulation loss in distinct evolutionary lineages of gut Firmicutes. a Prediction of sporulation capability in human-associated Firmicutes families based on the presence of 66 sporulation-associated genes. Erysipelotrichaceae, Peptostreptococcaceae, Clostridiaceae, Ruminococcaceae, and Lachnospiraceae families have a bimodal pattern with genomes either having a high scoring (blue dots) (classified as Spore-Formers) or a low scoring sporulation signature score (red dots) (classified as Former-Spore-Formers). Lactobacillaceae, Enterococcaceae, Actinobacteria, Bacteroidetes, and Proteobacteria are all non-spore-forming (yellow dots) and contain low scoring genomes that lack spo0A which is essential for sporulation. b Presence and absence of sporulation signature genes were determined in gut-associated Spore-Formers (SF) (n=456) and Former-Spore-Formers (FSF) (n=117) bacteria. FSF have less sporulation signature genes for all sporulation stages compared to SF (all stages q< 0.0001, except for stage 0 q=0.0491, Fisher’s exact test, adjusted for multiple testing). The cartoon describes sporulation stages. c Phylogeny of the Firmicutes constructed from 40 universal protein-coding genes extracted from 1358 whole-genome sequences. Sporulation has been lost at large taxonomic scales (Lactobacillales order) and at small taxonomic scales (within host-associated Erysipelotrichales and Clostridiales orders). Major taxonomic orders are indicated by branch colors and name, black branches at the base of phylogeny represent non-Firmicutes root derived from Actinobacteria genomes