Closely related NDM-1-encoding plasmids from Escherichia coli and Klebsiella pneumoniae in Taiwan.

Chao-Ju Chen,Ying-Tsong Chen,Yin-Ching Chuang,Jung-Chung Lin,Po-Liang Lu,Chang-Phone Fung,L. Kristopher Siu,Tsu-Lan Wu,Franklin D. Lowy

doi:10.1371/journal.pone.0104899

Abstract

ObjectiveTwo plasmids carrying bla NDM-1 isolated from carbapenem-resistant Klebsiella pneumoniae (CR-KP) and carbapenem-resistant Escherichia coli (CR-EC) were sequenced. CR-KP and CR-EC were isolated from two Taiwanese patients without travel histories.MethodsComplete sequencing of the plasmids (pLK75 and pLK78) was conducted using a shotgun approach. Annotation of the contigs was performed using the RAST Server, followed by manual inspection and correction.ResultsThese similar plasmids were obtained from two patients with overlapping stays at the same hospital. The pLK75 and pLK78 plasmids were 56,489-bp and 56,072-bp in length, respectively. Plasmid annotation revealed a common backbone similar to the IncN plasmid pR46. The regions flanking the bla NDM-1 genes in these plasmids were very similar to plasmid pNDM-HU01 in Japan, which contains a complex class 1 integron located next to an ISCR1 element. The ISCR1 element has been suggested to provide a powerful mechanism for mobilising antibiotic resistance genes.ConclusionTwo indigenous NDM-1-producing Enterobacteriaceae cases were identified for the first time in Taiwan, highlighting the alarming introduction of NDM-1-producing Enterobacteriaceae in this region.

Highlights

New Delhi metallo-b-lactamase 1 (NDM-1) is a novel metallo-blactamase (MBL) that was first identified in 2009 [1]
NDM-1 positive bacteria have been detected in the UK, India, Pakistan and Bangladesh during 2008–2009 [2]
Plasmids encoding blaNDM-1 were initially observed in Klebsiella pneumoniae and Escherichia coli

Summary

Results

These similar plasmids were obtained from two patients with overlapping stays at the same hospital. The pLK75 and pLK78 plasmids were 56,489-bp and 56,072-bp in length, respectively. Plasmid annotation revealed a common backbone similar to the IncN plasmid pR46. The regions flanking the blaNDM-1 genes in these plasmids were very similar to plasmid pNDM-HU01 in Japan, which contains a complex class 1 integron located next to an ISCR1 element. The ISCR1 element has been suggested to provide a powerful mechanism for mobilising antibiotic resistance genes

Introduction

Materials and Methods

Results and Discussion