%0 Journal Article
%T The Genetic Structures of an Extensively Drug Resistant (XDR) Klebsiella pneumoniae and Its Plasmids.
%A Li L
%A Yu T
%A Ma Y
%A Yang Z
%A Wang W
%A Song X
%A Shen Y
%A Guo T
%A Kong J
%A Wang M
%A Xu H
%J Front Cell Infect Microbiol
%V 8
%N 0
%D 2018
%M 30662878
%F 6.073
%R 10.3389/fcimb.2018.00446
%X Multi-, extensively-, and pan-drug resistant bacteria are a threat to our health today, because their wide resistance spectra make their infections difficult to cure. In this work, we isolated an extensively drug resistant (XDR) Klebsiella pneumoniae 2-1 strain from the stool sample of a patient diagnosed of colorectal cancer. K. pneumoniae 2-1 was found to be resistant to all the antibiotics tested except for cefepime, tigecycline, and ceftazidime-avibactam. By sequencing the complete genome of K. pneumoniae 2-1, we found it contains a chromosome of 5.23 Mb and two circular plasmids with the size of 246 and 90 kb. The larger plasmid, pKP21HI1 was found to be a new conjugation-defective plasmid belonging to incompatibility group HI1B and a new sequence type. Further comparative genomics analysis and antimicrobial resistance gene analysis showed that although a great deal of changes took place on the chromosome of K. pneumoniae 2-1 in comparison with the reference genome, the extensively drug resistance phenotype of K. pneumoniae 2-1 is primarily due to the two multidrug resistant plasmids it contains. This work explains the genetic and mechanistic basis of the extensive drug resistance of K. pneumoniae 2-1, and found that plasmids play key roles in the strong antibiotic resistance of bacteria.