First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital.
Tigecycline is one of the few therapeutic options for treating infections caused by some multi-drug resistant pathogens, such as Klebsiella pneumoniae. However, tigecycline-resistant K. pneumoniae has been discovered recently in China. From 2009 to 2013, nine tigecycline-resistant K. pneumoniae isol...
Main Authors: | , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2014-01-01
|
Series: | PLoS ONE |
Online Access: | http://europepmc.org/articles/PMC4264890?pdf=render |
id |
doaj-d177971faa8f4b5dbd212c7898fb51d8 |
---|---|
record_format |
Article |
spelling |
doaj-d177971faa8f4b5dbd212c7898fb51d82020-11-24T21:55:25ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-01912e11518510.1371/journal.pone.0115185First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital.Xue ZhongHongtao XuDongke ChenHaijian ZhouXin HuGang ChengTigecycline is one of the few therapeutic options for treating infections caused by some multi-drug resistant pathogens, such as Klebsiella pneumoniae. However, tigecycline-resistant K. pneumoniae has been discovered recently in China. From 2009 to 2013, nine tigecycline-resistant K. pneumoniae isolates were identified in our hospital. Six of nine strains were identified before using tigecycline. To investigate the efflux-mediated resistance mechanisms of K. pneumoniae, the expression of efflux pump genes (acrA, acrB, tolC, oqxA and oqxB) and pump regulators (acrR, marA, soxS, rarA, rob and ramA) were examined by real-time RT-PCR. Molecular typing of the tigecycline resistant strains was performed. ST11 was the predominant clone of K. pneumoniae strains, while ST1414 and ST1415 were novel STs. Efflux pump inhibitor (EPI)-carbonyl cyanide chlorophenylhydrazone (CCCP) was able to reverse the resistance patterns of 5 resistant K. pneumoniae strains. In comparison with strain A111, a tigecycline-susceptible strain (negative control), we found that the expression levels of efflux pump genes and pump regulators were higher in a majority of resistant strains. Higher expression levels of regulators rarA (2.41-fold, 9.55-fold, 28.44-fold and 18.31-fold, respectively) and pump gene oqxB (3.87-fold, 31.96-fold, 50.61-fold and 29.45-fold, respectively) were observed in four tigecycline resistant strains (A363, A361, A368, A373, respectively). Increased expression of acrB was associated with ramA and marA expression. To our knowledge, studies on tigecycline resistance mechanism in K. pneumoniae are limited especially in China. In our study, we found that both efflux pump AcrAB-TolC and OqxAB contributed to tigecycline resistance in K. pneumoniae isolates.http://europepmc.org/articles/PMC4264890?pdf=render |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Xue Zhong Hongtao Xu Dongke Chen Haijian Zhou Xin Hu Gang Cheng |
spellingShingle |
Xue Zhong Hongtao Xu Dongke Chen Haijian Zhou Xin Hu Gang Cheng First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. PLoS ONE |
author_facet |
Xue Zhong Hongtao Xu Dongke Chen Haijian Zhou Xin Hu Gang Cheng |
author_sort |
Xue Zhong |
title |
First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. |
title_short |
First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. |
title_full |
First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. |
title_fullStr |
First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. |
title_full_unstemmed |
First emergence of acrAB and oqxAB mediated tigecycline resistance in clinical isolates of Klebsiella pneumoniae pre-dating the use of tigecycline in a Chinese hospital. |
title_sort |
first emergence of acrab and oqxab mediated tigecycline resistance in clinical isolates of klebsiella pneumoniae pre-dating the use of tigecycline in a chinese hospital. |
publisher |
Public Library of Science (PLoS) |
series |
PLoS ONE |
issn |
1932-6203 |
publishDate |
2014-01-01 |
description |
Tigecycline is one of the few therapeutic options for treating infections caused by some multi-drug resistant pathogens, such as Klebsiella pneumoniae. However, tigecycline-resistant K. pneumoniae has been discovered recently in China. From 2009 to 2013, nine tigecycline-resistant K. pneumoniae isolates were identified in our hospital. Six of nine strains were identified before using tigecycline. To investigate the efflux-mediated resistance mechanisms of K. pneumoniae, the expression of efflux pump genes (acrA, acrB, tolC, oqxA and oqxB) and pump regulators (acrR, marA, soxS, rarA, rob and ramA) were examined by real-time RT-PCR. Molecular typing of the tigecycline resistant strains was performed. ST11 was the predominant clone of K. pneumoniae strains, while ST1414 and ST1415 were novel STs. Efflux pump inhibitor (EPI)-carbonyl cyanide chlorophenylhydrazone (CCCP) was able to reverse the resistance patterns of 5 resistant K. pneumoniae strains. In comparison with strain A111, a tigecycline-susceptible strain (negative control), we found that the expression levels of efflux pump genes and pump regulators were higher in a majority of resistant strains. Higher expression levels of regulators rarA (2.41-fold, 9.55-fold, 28.44-fold and 18.31-fold, respectively) and pump gene oqxB (3.87-fold, 31.96-fold, 50.61-fold and 29.45-fold, respectively) were observed in four tigecycline resistant strains (A363, A361, A368, A373, respectively). Increased expression of acrB was associated with ramA and marA expression. To our knowledge, studies on tigecycline resistance mechanism in K. pneumoniae are limited especially in China. In our study, we found that both efflux pump AcrAB-TolC and OqxAB contributed to tigecycline resistance in K. pneumoniae isolates. |
url |
http://europepmc.org/articles/PMC4264890?pdf=render |
work_keys_str_mv |
AT xuezhong firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital AT hongtaoxu firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital AT dongkechen firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital AT haijianzhou firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital AT xinhu firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital AT gangcheng firstemergenceofacrabandoqxabmediatedtigecyclineresistanceinclinicalisolatesofklebsiellapneumoniaepredatingtheuseoftigecyclineinachinesehospital |
_version_ |
1725862790299648000 |