Zhu Yuying, Yi Yong, Liu Fei, Lv Na, Yang Xi, Li Jing, Hu Yongfei, Zhu Baoli
Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Beijing Key Laboratory of Microbial Drug Resistance and Resistome, Beijing 100101, China.
The 306th Hospital of People's Liberation Army, Beijing 100101, China.
Microbiol Res. 2014 Nov;169(11):811-6. doi: 10.1016/j.micres.2014.04.002. Epub 2014 Apr 18.
The class 1 integron is an important driver of the nosocomial dissemination of multidrug-resistant (MDR) bacteria, such as Acinetobacters. In this study, we characterized the gene cassette arrays of class 1 integrons in Acinetobacter baumannii, where the detailed structure of these integrons for 38 clinical strains was analyzed. The results showed that there are three types of gene cassette arrays that are carried by different class 1 integrons, among them the aac(6')-IId-catB8-aadA1 array was the most prevalent. For detailed analysis of the integron structure, whole genome sequencing was carried out on strain AB16, and it was found that a single integron on its chromosome has a partial Tn21 transposon in its 5' flanking region and two complete copies of the insertion element IS26 in both the 5' and 3' flanking regions, indicating that the integron could be acquired by horizontal gene transfer. Furthermore, there is one resistance island AbaR22, one bla gene containing a transposon, four intrinsic resistant genes and one efflux pump that together confer six types of antibiotic resistance.
1类整合子是多重耐药（MDR）细菌如不动杆菌在医院内传播的重要驱动因素。在本研究中，我们对鲍曼不动杆菌中1类整合子的基因盒阵列进行了表征，分析了38株临床菌株中这些整合子的详细结构。结果表明，有三种类型的基因盒阵列由不同的1类整合子携带，其中aac(6')-IId-catB8-aadA1阵列最为普遍。为了详细分析整合子结构，对菌株AB16进行了全基因组测序，发现其染色体上的单个整合子在其5'侧翼区域有一个部分Tn21转座子，在5'和3'侧翼区域都有两个完整的插入元件IS26拷贝，这表明该整合子可能通过水平基因转移获得。此外，有一个耐药岛AbaR22、一个含有转座子的bla基因、四个固有耐药基因和一个外排泵，它们共同赋予六种类型的抗生素耐药性。
