Putative replication region of pSD15. (A) A 5-kb region
of pSD15 contains a putative replicase (MS100), helicase (MS102),
partition protein (MS101), five iterons, and a 316-bp AT-rich region.
(B) The sequence of the five iterons is shown, with the base-pair
position on pSD15 indicated in parentheses. Mismatched bases are
indicated in boldface.