We found that cells of Vibrio parahaemolyticus possess an energy-dependent efflux system for norfloxacin. cloned a gene putative norfloxacin protein from the chromosomal DNA V. by using Escherichia coli mutant lacking major multidrug AcrAB as host and sequenced (norM). Cells E. transformed with plasmid carrying norM showed elevated The transformants resistance not only to ciprofloxacin but also structurally unrelated compounds ethidium, kanamycin, streptomycin. These results suggest this is...

ABSTRACT Two new genes ( mexXY ) similar to mexAB , mexCD and mexEF mediating multidrug resistance were cloned from the chromosome of Pseudomonas aeruginosa . Elevated ethidium extrusion was observed with Escherichia coli cells harboring plasmid carrying This MexXY system confers higher fluoroquinolones than MexAB MexCD systems, E. TolC or P. OprM is necessary for function system.

Anti-pseudomonas aminoglycosides, such as amikacin and tobramycin, are used in the treatment of Pseudomonas aeruginosa infections. However, their use is linked to development resistance. During last decade, MexXY multidrug efflux system has been comprehensively studied, numerous reports laboratory clinical isolates have published. This increasingly recognized one primary determinants aminoglycoside resistance P. aeruginosa. In cystic fibrosis isolates, upregulation pump considered most...

ABSTRACT NorM of Vibrio parahaemolyticus apparently is a new type multidrug efflux protein, with no significant sequence similarity to any known transport proteins. Based on the following experimental results, we conclude that an Na + -driven /drug antiporter. (i) Energy-dependent ethidium from cells possessing was observed in presence but not K . (ii) An artificially imposed, inwardly directed gradient elicited cells. (iii) The addition loaded efflux. Thus, antiporting pump, first be found...

Corilagin and tellimagrandin I are polyphenols isolated from the extract of Arctostaphylos uvaursi Rosa canina L. (rose red), respectively. We have reported that corilagin remarkably reduced minimum inhibitory concentration (MIC) beta-lactams in methicillin-resistant Staphylococcus aureus(MRSA). In this study, we investigated effect on penicillin binding protein 2 '(2a) (PBP2 '(PBP2a)) which mainly confers resistance to beta-lactam antibiotics MRSA. These compounds when added culture medium...

The MexXY components of the MexXY-OprM multidrug efflux system Pseudomonas aeruginosa are encoded by a MexZ repressor-regulated operon that is inducible antibiotics target ribosome. Mutant strains disrupted in gene, PA5471, were shown to be compromised for drug-inducible mexXY expression and, therefore, MexXY-OprM-mediated antimicrobial resistance. PA5471 gene was same ribosome-targeting agents induce expression. Moreover, vector-driven cloned sufficient promote and MexXY-mediated resistance...

ABSTRACT Gene vmrA , cloned from Vibrio parahaemolyticus made Escherichia coli resistant to 4prime;,6-diamino-2-phenylindol, tetraphenylphosphonium chloride, acriflavine, and ethidium bromide. VmrA belongs the DinF branch of MATE family efflux transporters. catalyzed acriflavine showed Na + /drug transporter activity because addition -loaded cells caused efflux.

We cloned the gene PA1361 (we designated pmpM), which seemed to encode a multidrug efflux pump belonging MATE family, of Pseudomonas aeruginosa by PCR method using drug-hypersensitive Escherichia coli KAM32 strain as host. Cells E. possessing pmpM showed elevated resistance several antimicrobial agents. observed energy-dependent ethidium from cells gene. found that PmpM is an H(+)-drug antiporter, and this finding first reported case H(+)-coupled in family. Disruption reintroduction P....

Induction of the MexCD-OprJ multidrug efflux pump was investigated in wild-type Pseudomonas aeruginosa PAO1. induced by clinically important disinfectants such as benzalkonium chloride and chlorhexidine gluconate, some cytotoxic agents tetraphenylphosphonium chloride, ethidium bromide rhodamine 6G. not norfloxacin, tetracycline, chloramphenicol, streptomycin, erythromycin or carbenicillin, although they are substrates for pump. Cells PAO1 showed increased resistance to norfloxacin when grown...

Over-expression of AdeABC efflux pump stimulated continuously by the mutated AdeRS two component system has been found to result in antimicrobial resistance, even tigecycline (TGC) multidrug-resistant Acinetobacter baumannii (MRAB). Although insertion sequence, ISAba1, contributes one mutations, detail mechanism remains unclear. In present study we collected 130 TGC-resistant isolates from 317 carbapenem resistant MRAB (MRAB-C) isolates, and 38 them were characterized with ISAba1 adeS gene....

The emergence and spread of multidrug-resistant P. aeruginosa infections is great concern, as very few agents are effective against strains this species. Methanolic extracts from the Coptidis Rhizoma (the rhizomes Coptis japonica var. major Satake) or Phellodendri Cortex bark Phellodendron chinense Schneider) markedly reduced resistance to anti-pseudomonal aminoglycosides (e.g., amikacin) in strains. Berberine, most abundant benzylisoquinoline alkaloid two extracts, aminoglycoside via a...

ABSTRACT Acinetobacter baumannii is highly resistant to antimicrobial agents, and XDR strains have become widespread. A. has developed resistance colistin, which considered the last resort against Gram-negative bacteria, mainly caused by lipooligosaccharide (LOS) phosphoethanolamine (pEtN) and/or galactosamine (GalN) modifications induced mutations that activate two-component system (TCS) pmrAB . Although PmrAB of been recognized as a drug factor, its function TCS, including regulatory genes...

To envisage the roles of MexXY- and MexAB-multidrug efflux pumps in intrinsic multidrug resistance wild-type strain Pseudomonas aeruginosa PAO1, we constructed mutants lacking either individual or both pumps. A mutant MexXY showed increased susceptibility to aminoglycosides, erythromycin, tetracycline, but not beta-lactams, chloramphenicol, quinolones. MexAB nalidixic acid, fluoroquinolones. an all antimicrobial agents tested compared with wild type. Very similar results were obtained a...

ABSTRACT Genes ( ebrAB ) responsible for ethidium resistance were cloned from chromosomal DNA of Bacillus subtilis ATCC 9372. The recombinant plasmid produced elevated against bromide, acriflavine, pyronine Y, and safranin O not only in Escherichia coli but also B. . It caused an energy-dependent efflux E. EbrA EbrB showed high sequence similarity with members the small multidrug (SMR) family pumps. Neither ebrA nor ebrB was sufficient resistance, introduction two genes carried on different...

The Pseudomonas aeruginosa nalD gene encodes a TetR family repressor with homology to the SmeT and TtgR repressors of smeDEF ttgABC multidrug efflux systems Stenotrophomonas maltophilia putida, respectively. A sequence upstream mexAB-oprM overlapping second promoter for this system was very similar operator sequences, NalD binding region was, in fact, demonstrated. Moreover, increased expression from seen mutant, consistent directly controlling promoter.

The multiresistant taxonomic outlier Pseudomonas aeruginosa PA7 possesses the conserved efflux genes, mexXY; however these are linked to a unique gene encoding an outer membrane channel, dubbed oprA, that is absent in most P. strains. Using genetic knockouts and single copy chromosomal complementation, we showed aminoglycoside resistance mediated part by MexXY-OprA pump, intriguingly MexXY this strain can utilize either OprA or OprM mexAB genes. We also identified small portion of oprA...

The emergence of multidrug-resistant Pseudomonas aeruginosa has become a serious problem in medical settings. P. clinical isolate PA7 is resistant to fluoroquinolones, aminoglycosides, and most -lactams but not imipenem. In this study, enhanced efflux-mediated fluoroquinolone resistance was shown reflect increased expression two nodulation cell division (RND) -type multidrug efflux operons, mexEF-oprN mexXY-oprA. Such rarely been reported because MexEF-OprN-overproducing mutants often...

We constructed a series of deletion mutants lacking all the four major mex operons for Mex multidrug efflux pumps or possessing each one from Pseudomonas aeruginosa PAO1. The drug specificity MexAB-OprM, MexXY-OprM and MexCD-OprJ was investigated. Surprisingly, we found that an inducible pump, inducers which were tetraphenylphosphonium chloride, ethidium bromide, rhodamine 6G acriflavine. Fluoroquinolones, chloramphenicol, erythromycin tetracycline not although they substrates MexCD-OprJ.

NorM is a member of the multidrug and toxic compound extrusion (MATE) family functions as Na+/multidrug antiporter in Vibrio parahaemolyticus, although underlying mechanism antiport unknown. Acidic amino acid residues Asp32, Glu251, Asp367 transmembrane region are conserved one clusters MATE family. In this study, we investigated role(s) acidic by site-directed mutagenesis. Wild-type mutant proteins with replacements D32E (D32 to E), D32N, D32K, E251D, E251Q, D367A, D367E, D367N, D367K were...

A gene responsible for multidrug resistance was cloned from the chromosomal DNA of non-O1 Vibrio cholerae NCTC 4716 by using as a host drug-hypersensitive Escherichia coli strain KAM32, which lacks major efflux pumps. E. cells transformed with showed elevated levels to number structurally dissimilar drugs, such tetracycline, norfloxacin, ciprofloxacin, doxorubicin, daunomycin, 4',6-diamidino-2-phenylindole, and Hoechst 33342. We determined nucleotide sequence found one open reading frame....