title: A Common Flanking Region in Promiscuous Plasmids Encoding blaNDM-1 in Klebsiella pneumoniae Isolated in Singapore.
abstract: Bacteria encoding the New Delhi metallo-β-lactamase gene (blaNDM-1) are regarded as superbugs for their resistance to multiple antibiotics. Plasmids encoding blaNDM-1 have been observed to be spreading among gram-negative bacteria around the world. Previous studies have demonstrated that multiple modifications of blaNDM-1-harboring plasmids might contribute to the spread of the gene. In this study, we analyzed blaNDM-1-encoding plasmids from two Klebsiella pneumoniae isolates, DU7433 and DU1301, found to be unrelated by pulsed field gel electrophoresis and multilocus sequencing typing (DU7433: ST14 and DU1301: ST11), and compared them with previously published plasmids. Although strains DU1301, DU7433, and previously published strain DU43320 carried unrelated plasmids, their transconjugants exhibited similar antimicrobial resistance profiles. Transconjugants lacked the resistance to aztreonam, ciprofloxacin, gentamicin, tetracycline, and trimethoprim/sulfamethoxazole when compared with the corresponding clinical isolates. Plasmids pTR1 from DU1301 and pTR2 from DU7433 had completely different plasmid backbones except a short conserved region of blaNDM-1 and ble flanked with truncated or nontruncated ISAba125 and trpF. The presence of this common region among known blaNDM-1-carrying plasmids implies that the dissemination of blaNDM-1 may be facilitated by mobilization of this conserved immediate region among different plasmids. Control measures should be strictly enforced whenever increasing incidences of epidemiological unrelated strains were identified.
authors: 1 Institute of Molecular and Genomic Medicine, National Health Research Institutes , Zhunan, Taiwan .|2 Institute of Genomics and Bioinformatics, National Chung Hsing University , Taichung, Taiwan .|3 Biotechnology Center, National Chung Hsing University , Taichung, Taiwan .
authors: Ying-Tsong
authors: YT
authors: Chen
authors: 4 National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes , Zhunan, Taiwan .|5 PhD Program for Aging, College of Medicine, China Medical University , Taichung, Taiwan .
authors: L Kristopher
authors: LK
authors: Siu
authors: 4 National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes , Zhunan, Taiwan .
authors: Yu-Kuo
authors: YK
authors: Tsai
authors: 4 National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes , Zhunan, Taiwan .
authors: Fu-Mei
authors: FM
authors: Lin
authors: 6 Department of Pathology, Singapore General Hospital , Singapore , Singapore.
authors: Tse Hsien
authors: TH
authors: Koh
authors: 7 Department of Medical Laboratory Science and Biotechnology, Yuanpei University of Medical Technology , Hsinchu, Taiwan .
authors: Jiun-Han
authors: JH
authors: Chen
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001398:Aztreonam / Q000494:pharmacology; D001483:Base Sequence; D002939:Ciprofloxacin / Q000494:pharmacology; D003227:Conjugation, Genetic; D017124:Conserved Sequence; D004269:DNA, Bacterial / Q000235:genetics*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D015870:Gene Expression; D005839:Gentamicins / Q000494:pharmacology; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism*; D012846:Singapore; D013752:Tetracycline / Q000494:pharmacology; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D005839:Gentamicins; D002939:Ciprofloxacin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1; D013752:Tetracycline; D001398:Aztreonam