FIG. 1.

Phylogenetic analysis of replication proteins expressed by bifidobacterial plasmids. The replication proteins encoded by bifidobacterial plasmids and other homologous replication proteins were compared by ClustalW multiple alignments (313). A phylogenetic tree was generated by the neighbor-joining method, using P distance values (307). The numbers associated with the branches represent the bootstrap values. Bifidobacterial plasmid replicons are indicated in bold. Roman numerals indicate the five different classes of replication proteins expressed from bifidobacterial plasmids.