Agarose gels of PCRs probing for AME genes in various ATCC strains and clinical isolates. Strains of (A) clinically isolated MRSA USA 100, USA 200, USA 300, and USA 600, (B) S. aureus ATCC 29213, S. aureus ATCC 33591, and an uncategorized MRSA, and (C) B. cereus ATCC 11778 tested for aac(6′)-Ib (lane 1), aac(3)-IV (lane 2), ant(2″)-Ia (lane 3), and aph(3′)-Ia (lane 4). L1 and L2 represent 100-bp and 1-kb DNA ladders, respectively. Expected band sizes are as follows: aac(6′)-Ib, 482 bp; aac(3)-IV, 230 bp; ant(2″)-Ia, 534 bp; aph(3′)-Ia, 624 bp.