Fig. 4

Expansion of protein families and phylogenetic diversity (PD) in the genus Clostridium. (a) Changes in the size of the core and accessory genome and PD (defined as the sum of branch lengths in a phylogenetic species tree) of solventogenic clostridia species after adding the newly sequenced Clostridium genomes. (b) Collector’s curve indicates the total increase in the number of protein families in the genus Clostridium before and after adding the new genomes. (c). Collector’s curve indicates the total increase in PD in the genus Clostridium.