Virulence ( IF 5.2 ) Pub Date : 2020-12-29 , DOI: 10.1080/21505594.2020.1859274 F Morales-León 1, 2, 3 , A Opazo-Capurro 1, 2 , C Caro 1, 3 , N Lincopan 4, 5 , A Cardenas-Arias 4 , F Esposito 4, 5 , V Illesca 6 , M L Rioseco 7 , M Domínguez-Yévenes 1 , C A Lima 1, 2 , H Bello-Toledo 1, 2 , Gerardo González-Rocha 1, 2
ABSTRACT
Convergence of virulence and antibiotic-resistance has been reported in Klebsiella pneumoniae, but not in Klebsiella variicola. We, hereby, report the detection and genomic characterization of hypervirulent and hypermucoviscous K. pneumoniae and K. variicola recovered in Chile from health-care associated infections, which displayed resistance to broad-spectrum cephalosporins. One hundred forty-six K. pneumoniae complex isolates were screened by hypermucoviscosity by the “string test.” Two hypermucoid isolates, one hypermucoviscous K. pneumoniae (hmKp) and one K. variicola (hmKv), were further investigated by whole-genome sequencing. In vivo virulence was analyzed by the Galleria mellonella killing assay. In silico analysis of hmKp UCO-494 and hmKv UCO-495 revealed the presence of multiple antibiotic-resistance genes, such as bla CTX-M-1, bla DHA-1 and bla LEN-25 among others clinically relevant resistance determinants, including mutations in a two-component regulatory system related to colistin resistance. These genetic features confer a multidrug-resistant (MDR) phenotype in both strains. Moreover, virulome in silico analysis confirmed the presence of the aerobactin gene iutA, in addition to yersiniabactin and/or colicin V encoding genes, which are normally associated to high virulence in humans. Furthermore, both isolates were able to kill G. mellonella and displayed higher virulence in comparison with the control strain. In summary, the convergence of virulence and the MDR-phenotype in K. pneumoniae complex members is reported for the first time in Chile, denoting a clinical problem that deserves special attention and continuous surveillance in South America.
中文翻译:
智利的高毒力和超粘液产生超广谱 β-内酰胺酶的肺炎克雷伯菌和天花克雷伯菌
摘要
在肺炎克雷伯菌中已经报道了毒力和抗生素抗性的融合,但在天花克雷伯菌中没有报道。我们特此,报告检测和超强和hypermucoviscous的基因组鉴定肺炎克雷伯菌和K. variicola在智利恢复从医疗保健相关的感染,这显示广谱头孢菌素耐药。一四六肺炎克雷伯复杂的菌株通过hypermucoviscosity通过筛选“字符串的考验。” 通过全基因组测序进一步研究了两种超粘液分离株,一种超粘液性肺炎克雷伯菌(hmKp) 和一种天花克雷伯菌(hmKv) 。通过大蜡螟杀死试验分析体内毒力。hmKp UCO-494 和 hmKv UCO-495 的计算机分析显示存在多个抗生素抗性基因,例如bla CTX-M-1、bla DHA-1和bla LEN-25以及其他临床相关的抗性决定因素,包括突变在与粘菌素抗性相关的双组分调节系统中。这些遗传特征赋予两种菌株多药耐药 (MDR) 表型。此外,计算机病毒组分析证实了厌氧菌素基因iutA的存在,除了耶尔森菌素和/或大肠杆菌素 V 编码基因,这些基因通常与人类的高毒力有关。此外,与对照菌株相比,两种分离株都能够杀死大蜡螟菌并显示出更高的毒力。总之,在智利首次报道了肺炎克雷伯氏菌复合体成员的毒力和 MDR 表型的趋同,这表明南美洲值得特别关注和持续监测的临床问题。