FIG. 3.

Southern hybridization with seven different IS-like elements. DNA probes RSα, ISB27B, FK1, RSβ, IS1632, ISB20, and IS1631 were prepared from plasmids pαHD7, pC27HD8, pK09HD1, pT14HD4, pβHD6, pT20HD4, and pT27HD5, respectively. Total DNAs from B. elkanii USDA76 and B. japonicum USDA110, NC4a, NK2, T7, NC3a, NK5, T2, and USDA123 were digested with BamHI for RSα-, ISB27B-, FK1-, IS1632-, and IS1631-specific hybridization, with XhoI for RSβ-specific hybridization, and with HindIII for ISB20-specific hybridization. The digested DNAs from each strain (3 μg/lane) were electrophoresed in 0.8% agarose-TAE (14), blotted onto a nylon filter, and hybridized with the radioactive probes. B. japonicum HRS strains (#) generally had numerous hybridization bands. This result is not due to overloading on the agarose gel or to partial digestion of total DNA as described previously (17, 18).