Fig. 2

Maximum likelihood phylogenetic tree of 216 C. perfringens strains. According to their phylogenetic relationships, the genomes were classified into five clades. The presence and absence of typical C. perfringens toxin genes, such as chromosomal plc, colA, pfoA, cpb2, and cpe (chromosomal or plasmid-borne), and plasmid-borne netB, alv, netF, tpeL, cpb, etx, becA, becB, iap, ibp, and lam (encoding the thermolysin-like metalloprotease called lambda toxin) [30], are indicated as different colour cells: black for the presence of chromosomal toxin genes, grey for the presence of plasmid-borne toxin genes, and light grey for the absence of the toxin gene. The toxinotyping of C. perfringens was determined based on the classification scheme proposed by Rood and co-workers and is indicated with seven colours [10]. In this study, the strains harbouring netB and cpe were classified as type G. The presence of the Pcp locus is shown as a red cell. Strain 13, which has pCP13, a representative plasmid of the pCP13-like family, is highlighted in blue, and the six bec-harbouring strains are highlighted in green