Figure 2. Pulsed-field gel electrophoresis (PFGE) of colonization/infection pairs. PFGE of SmaI DNA digests of paired vancomycin-resistant enterococci isolates from nine patients with infection acquired in the intensive care unit. First colonizing rectal isolates are designated 1R to 9R. The corresponding first-infected site isolate from the same patient is designated 1I to 9I. End lanes contain NotI-digested Enterococcus faecalis OGIRF molecular weight marker. Band sizes are shown to the left in kilobase (kb) pairs. Patients 1 to 4 are in panel A, patients 5 to 9 in panel B.