Southern blot hybridization of EcoRI-digested total DNA from a selection of R. gnavus E1 phylogenetically related strains using an ISRgn1-specific probe. Sizes of the fragments containing a copy of the insertion sequence are indicated (in kilobases) on the right. Lane 1, R. gnavus ATCC 29149T; lane 2, R. gnavus LEMG25; lane 3, R. gnavus LEMV95; lane 4, R. gnavus LEMV99; lane 5, R. gnavus LEMB86; lane 6, R. gnavus LEMV62; lane 7, R. gnavus LEMV50; lane 8, R. gnavus LEMV58; lane 9, R. gnavus LEMV66; lane 10, R. gnavus LEMB53; lane 11, R. hansenii DSMZ 20583T; lane 12, R. hansenii LEMV98; lane 13, C. nexile DSMZ 1787T; lane 14, C. nexile LEMB04; lane 15, New operational taxonomic unit (OTU) LEMV61; lane 16, New OTU LEMV78; lane 17, New OTU LEMV63; lane 18, R. gnavus E1 Bac−, which was included as a positive control. ATCC and DSMZ strains were laboratory reference strains from American Type Culture Collection (Manassas, Va.) and Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH (Braunschweig, Germany), respectively. The other strains were from our laboratory collection and are available upon request.