title: [Discovery of new structure of class 1 integron in MDR Pseudomonas aeruginosa and its association with drug-resistance].
abstract: OBJECTIVE
  To investigate the characteristics of class I integrons among clinical multidrug-resistant Pseudomonas aeruginosa isolates, and to analyze the association between class I integrons and multidrug resistance.
  
  
  METHODS
  Pseudomonas aeruginosa strains were isolated from clinical samples, and the multidrug-resistant ones were picked out from these isolates. PCR assays were used to detect the variable regions of class I integrons, and the resulting products were then digested with restriction enzyme Sau 3A I and sequenced. SPSS19.0 software was used for statistical analysis.
  
  
  RESULTS
  Class I integrons were detected in 27.3% of the clinical multidrug-resistant Pseudomonas aeruginosa isolates. Amplification of variable regions of class I integrons revealed three different gene cassette arrays (1500, 2300 and 4000 bp), two of them were also found in other bacteria. These gene cassette arrays encoded aminoglycoside-modifying enzymes (aadA, aadB, aac(6') II and aadA13), beta-lactamases (blaCARB8 and oxa10) and chloromycetin efflux pump (cmlA8). Analysis results suggested closely relationship between class I integrons and aminoglycoside resistance.
  
  
  CONCLUSIONS
  We revealed three different gene cassette arrays in the clinical isolates of the multidrug-resistant Pseudomonas aeruginosa, and gene cassette array aadB-aac(6') II -blaCARB8 was the most prevalent. The three gene cassette arrays all contained the aminoglycoside-resistant genes.
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China. ying.yu.zhu@163.com
authors.forename: Yuying
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: The 306th Hospital of People's Liberation Army, Beijing 100101, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Na
authors.initials: N
authors.lastname: Lv
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Baoli
authors.initials: B
authors.lastname: Zhu
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Hu
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial; D032023:Integrons; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001618:beta-Lactamases