Abstract:
:The purpose of this study was to examine expression and regulation of 6 multidrug efflux systems, including MexAB-OprM, MexCD-OprJ, MexEF-OprN, MexXY, MexJK, and MexVW, in 13 non-cystic fibrosis (CF) clinical isolates of Pseudomonas aeruginosa. These isolates displayed a high level of resistance to many clinically important antibiotics. Some isolates simultaneously overexpressed up to 4 different Mex systems, as determined by quantitative real-time reverse transcription PCR. None of the isolates overexpressed MexCD-OprJ, and only 1 isolate overproduced MexJK. All the isolates overexpressed MexXY, while overexpression of MexEF-OprN and MexVW was common. DNA sequencing analysis of regulatory genes showed that no clear correlation could be established among (i) the presence of mutations, (ii) the type of mutations, (iii) the expression level of the Mex systems, and (iv) resistance to antibiotic substrates. The results suggest that the concomitant overexpression of some Mex systems may superimpose their antimicrobial drug efflux capabilities, contributing to the multidrug resistance phenotype in the P. aeruginosa non-CF clinical isolates. The existence of uncharacterized regulators for the Mex systems was signified.
journal_name
Can J Microbioljournal_title
Canadian journal of microbiologyauthors
Poonsuk K,Tribuddharat C,Chuanchuen Rdoi
10.1139/cjm-2014-0239subject
Has Abstractpub_date
2014-07-01 00:00:00pages
437-43issue
7eissn
0008-4166issn
1480-3275journal_volume
60pub_type
杂志文章abstract::Ten bacterial strains were isolated by enrichment culture, using as carbon sources either aliphatics or an aromatic-polar mixture. Oxygen uptake rate was used as a criterion to determine culture transfer timing at each enrichment stage. Biodegradation of aliphatics (10,000 mg L(-1)) and an aromatic-polar mixture (5000...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w03-098
更新日期:2003-12-01 00:00:00
abstract::Fifty-two killer, factor-resistant, nuclear mutants were isolated from sensitive strains of yeast and assorted into three functional groups. All but one mutant owed their resistance to an alteration in the cell wall binding site for killer. In several mutant strains, an alteration at the site of killer binding was ass...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:1978-03-01 00:00:00
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journal_title:Canadian journal of microbiology
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doi:10.1139/m76-036
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journal_title:Canadian journal of microbiology
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更新日期:1978-05-01 00:00:00
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journal_title:Canadian journal of microbiology
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journal_title:Canadian journal of microbiology
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doi:10.1139/m75-028
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m76-251
更新日期:1976-12-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-124
更新日期:1978-06-01 00:00:00
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journal_title:Canadian journal of microbiology
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更新日期:2009-07-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:1994-05-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w04-095
更新日期:2004-12-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2018-0087
更新日期:2018-11-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m90-136
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章,评审
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更新日期:2015-02-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-201
更新日期:1980-10-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w2012-037
更新日期:2012-05-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/W08-098
更新日期:2008-12-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1994-10-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:1989-03-01 00:00:00
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journal_title:Canadian journal of microbiology
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:2016-01-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:2005-06-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m75-024
更新日期:1975-02-01 00:00:00
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journal_title:Canadian journal of microbiology
pub_type: 杂志文章
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更新日期:2001-07-01 00:00:00