Cluster 1 and 2 C. perfringens homologs of known sporulation genes summarized by Galperin and colleagues [8]*.

* Homologs of the known sporulation genes summarized in reference [8] but that do not have specific sporulation-associated increased expression (grouped in Clusters 3–6) can be retrieved from S1 Table.** Locus tags of C. perfringens homologs are shown with their assigned C. perfringens gene names, gene names of the Bacillus genes are bracketed, and locus tags of C. difficile 630 are preceded by ‘CD’.Cluster 1 and 2 C. perfringens homologs of known sporulation genes summarized by Galperin and colleagues [8]*.