The enteropathogen Yersinia pseudotuberculosis causes gastrointestinal infections in humans. Although this species is usually susceptible to antibiotics active against Gram-negative bacteria, we identified three multidrug resistant (MDR) strains of Y. pseudotuberculosis that were isolated from the environment in Russia and from a patient in France. The resistance traits of the two Russian isolates were transferable at high frequencies (≈2×10-1/donor CFU) to Y. pseudotuberculosis. In contrast no transfer of the antibiotic resistances carried by the French strain was observed. Sequencing of the plasmid extracts of the Y. pseudotuberculosis transconjugants for the Russian isolates revealed the presence of conjugative plasmids of the IncN group that carried genes conferring resistance to four to six classes of antibiotics. The French strain harbored a large MDR plasmid of the IncHI2 group that carried resistance genes to six families of antibiotics, and contained a truncated set of transfer genes, accounting for the lack of plasmid transfer. All three Y. pseudotuberculosis plasmids were homologous to MDR plasmids found in various enterobacteria. A phylogenetic analysis showed that the two Russian strain plasmids were closely related to each other and were more distant from the French plasmid. To the best of our knowledge, this is the first molecular characterization of MDR plasmids in Y. pseudotuberculosis. Due to the propensity of this species to acquire exogenous plasmids, the risk of emergence of new MDR Y. pseudotuberculosis isolates should be seriously taken into consideration.

中文翻译：

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假性耶尔森氏菌多药耐药性的分子基础。

肠病原性耶尔森氏菌假结核病会导致人类胃肠道感染。尽管该物种通常对具有革兰氏阴性菌活性的抗生素敏感，但我们鉴定了三种假单胞菌的多重耐药（MDR）菌株，它们从俄罗斯的环境和法国的患者中分离出来。两个俄罗斯分离株的抗性状可以高频（≈2×10-1 /供体CFU）转移至假结核耶尔森氏菌。相反，未观察到该法国菌株携带的抗生素抗性的转移。对俄罗斯分离株的假结核耶尔森氏菌转导结合体的质粒提取物进行测序，发现存在IncN组结合质粒，该质粒带有赋予对四到六类抗生素抗性的基因。该法国菌株含有IncHI2组的大型MDR质粒，该质粒携带对六个抗生素家族的抗性基因，并且含有一组截短的转移基因，这说明缺乏质粒转移。所有三种假结核耶尔森氏菌质粒均与各种肠杆菌中发现的MDR质粒同源。系统发育分析表明，两个俄罗斯菌株质粒彼此密切相关，与法国质粒距离较远。据我们所知，这是假结核耶尔森氏菌中MDR质粒的第一个分子表征。由于该物种倾向于获取外源质粒，因此应认真考虑出现新的MDR假结核分枝杆菌菌株的风险。