Molecular characterization of a multidrug-resistant strain of enteroinvasive Escherichia coli O164 isolated in Japan
Molecular characterization of a multidrug-resistant strain of enteroinvasive Escherichia coli O164 isolated in Japan
复制标题
DOI：
10.1099/jmm.0.45908-0
复制
发表时间：
2005-03-01
影响因子：
3
通讯作者：
Shimamoto, T
中科院分区：
文献类型：
--
作者：
Ahmed, AM;Miyoshi, S;Shimamoto, T
肠侵袭性大肠杆菌（EIEC）O 164菌株RIMD 05091045是从日本大坂机场检疫设施的一名腹泻旅行患者中分离出来的。该菌株对链霉素、大观霉素、复方新诺明和氨苄西林具有多重耐药性，对环丙沙星的敏感性降低。多药耐药表型的分子表征揭示了1类整合子的存在，包含三个基因，二氢叶酸还原酶XII型基因，dfrXII，赋予耐药性甲氧苄啶，氨基糖苷腺苷转移酶基因，aadA 2，赋予耐药性链霉素和壮观霉素，和未知功能的ORF。Southern印迹杂交和接合实验表明，1类整合子位于一个小于90 kb的可转移质粒上。发现EIEC 0164对氨苄西林的耐药性是由于TEM-1 β-内酰胺酶的存在。另一方面，一个单一的突变，以前没有被描述，P1 58-S，检测到的喹诺酮类药物耐药决定区的拓扑异构酶IV的parC的下游，并可能是负责降低敏感性环丙沙星在这个菌株。
Enteroinvasive Escherichia coli (EIEC) O164 strain RIMD05091045 was isolated from a travelling patient suffering from diarrhoea at the Osaka airport quarantine facility in Japan. The strain showed multidrug resistance against streptomycin, spectinomycin, co-trimoxazole (trimethoprim/sulfamethoxazole) and ampicillin, and reduced susceptibility to ciprofloxacin. Molecular characterization of the multidrug-resistance phenotype revealed the presence of a class 1 integron containing three genes, a dihydrofolate reductase type XII gene, dfrXII, which confers resistance to trimethoprim, an aminoglycoside adenyltransferase gene, aadA2, which confers resistance to streptomycin and spectinomycin, and an ORF of unknown function. Southern blot hybridization and conjugation experiments showed that the class 1 integron was located on a transferable plasm id that was less than 90 kb in size. The resistance of EIEC 0164 to ampicillin was found to be due to the presence of TEM-1 beta-lactamase. On the other hand, a single mutation that has not previously been described, P1 58-to-S, was detected downstream of the quinolone-resistance-determining region of parC of topoisomerase IV and may be responsible for the reduced susceptibility to ciprofloxacin in this strain.