Castanheira Mariana, Deshpande Lalitagauri M, Mills Janet C, Jones Ronald N, Soave Rosemary, Jenkins Stephen G, Schuetz Audrey N
JMI Laboratories, North Liberty, Iowa, USA
JMI Laboratories, North Liberty, Iowa, USA.
Antimicrob Agents Chemother. 2016 Jan 4;60(3):1924-7. doi: 10.1128/AAC.01844-15.
Among 69 of 139 (49.6%) carbapenem-nonsusceptible Enterobacteriaceae carrying blaKPC, 1 Klebsiella pneumoniae was also positive for blaVIM. The isolate belonged to sequence type 258 (ST258) and carried blaKPC-2 on a copy of Tn4401a and blaVIM-4 on a class 1 integron. Genes were located on distinct plasmids belonging to Inc types A/C and FII. Elevated expression of the efflux pump AcrAB-TolC (acrA, 15.3 times) and reduced expression of outer membrane protein genes ompK35 and ompK37 (0.16 and 0.081 times, respectively) associated with various amino acid alterations on OmpK37 were observed. The presence of two carbapenemases in ST258 K. pneumoniae is of great concern due to the ability of this organism to widely disseminate.
在139株携带blaKPC的碳青霉烯类不敏感肠杆菌科细菌中，有69株（49.6%），其中1株肺炎克雷伯菌的blaVIM也呈阳性。该分离株属于序列型258（ST258），在一个Tn4401a拷贝上携带blaKPC-2，在1类整合子上携带blaVIM-4。这些基因位于属于Inc A/C和FII型的不同质粒上。观察到外排泵AcrAB-TolC的表达升高（acrA为15.3倍），以及外膜蛋白基因ompK35和ompK37的表达降低（分别为0.16倍和0.081倍），这与OmpK37上的各种氨基酸改变有关。由于该菌株具有广泛传播的能力，ST258肺炎克雷伯菌中存在两种碳青霉烯酶备受关注。
