Representative PFGE patterns of carbapenem-resistant P. aeruginosa. Lanes: M, low-range PFGE marker (size are given in kilobases); 1, strain DU20080/00; 2, strain DU16517/00; 3, strain DU31106/00; 4, strain DU34565/00; 5, strain DU8622/00; 6, strain DU9519/00; 7, strain DM10075/00; 8, strain DU40799/00; 9, strain DU6061/00; 10, strain DU14610/00; 11, strain DM727/00. The PFGE patterns are indicated by the letters above the lane numbers.