FIG. 4.

The C. fetus subsp. venerealis genomic island exhibits a conserved position of chromosome insertion. PFGE of SmaI-digested C. fetus DNA (top), followed by Southern hybridization with a radioactively labeled orf21 probe (bottom), reveals a typical resolution of the unique gene region on a 240-kb fragment. The asterisks (top) identify hybridized fragments. The identification numbers above the lanes designate isolates of the strain collection, as listed parenthetically in Table S1 in the supplemental material. A PFGE-DNA ladder (New England Biolabs) served as a standard (ST).