PCR identification and characterization of new IS 711 insertion sites in B. abortus B12 and B16 field isolates. IS711-anchored PCR with: (A), primers IS711out-P5; or (B), RB51-P5. Site-specific PCR with: (C), primers BruAb1_0736F and BruAb1_0737R; or (D), forward and reverse primers of BruAb2_0461. For each lane, the number refers to the B. abortus strain used in the amplification. Arrows indicate specific PCR products generated from each strain. M, 1 kb DNA ladder (Fermentas); M2, 1 kb DNA ladder (Roche).