scholarly journals A Two-Component Multidrug Efflux Pump, EbrAB, in Bacillus subtilis

2000 ◽  
Vol 182 (8) ◽  
pp. 2307-2310 ◽  
Author(s):  
Yoko Masaoka ◽  
Yasuhiro Ueno ◽  
Yuji Morita ◽  
Teruo Kuroda ◽  
Tohru Mizushima ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Efflux Pump ◽  
Sequence Similarity ◽  
Multidrug Efflux ◽  
Chromosomal Dna ◽  
Multidrug Efflux Pump ◽  
High Sequence Similarity ◽  
Small Multidrug Resistance ◽  
Multidrug Efflux Pumps ◽  
Safranin O

ABSTRACT Genes (ebrAB) responsible for ethidium resistance were cloned from chromosomal DNA of Bacillus subtilis ATCC 9372. The recombinant plasmid produced elevated resistance against ethidium bromide, acriflavine, pyronine Y, and safranin O not only inEscherichia coli but also in B. subtilis. It also caused an elevated energy-dependent efflux of ethidium in E. coli. EbrA and EbrB showed high sequence similarity with members of the small multidrug resistance (SMR) family of multidrug efflux pumps. Neither ebrA nor ebrB was sufficient for resistance, but introduction of the two genes carried on different plasmids conferred drug resistance. Thus, both EbrA and EbrB appear to be necessary for activity of the multidrug efflux pump. In known members of the SMR family, only one gene produces drug efflux. Thus, EbrAB is a novel SMR family multidrug efflux pump with two components.

scholarly journals Functional Cloning and Characterization of a Multidrug Efflux Pump, MexHI-OpmD, from a Pseudomonas aeruginosa Mutant

2003 ◽  
Vol 47 (9) ◽  
pp. 2990-2992 ◽  
Author(s):  
Hiroshi Sekiya ◽  
Takehiko Mima ◽  
Yuji Morita ◽  
Teruo Kuroda ◽  
Tohru Mizushima ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Ethidium Bromide ◽  
Rhodamine 6G ◽  
Efflux Pump ◽  
Efflux Pumps ◽  
Multidrug Efflux ◽  
Chromosomal Dna ◽  
Multidrug Efflux Pump ◽  
Multidrug Efflux Pumps

ABSTRACT We isolated mutant YM644, which showed elevated resistance to norfloxacin, ethidium bromide, acriflavine, and rhodamine 6G, from Pseudomonas aeruginosa YM64, a strain that lacks four major multidrug efflux pumps. The genes responsible for the resistance were mexHI-opmD. Elevated ethidium extrusion was observed with cells of YM644 and YM64 harboring a plasmid carrying the genes. Disruption of the genes in the chromosomal DNA of YM644 made the cells sensitive to the drugs.

scholarly journals A Broad-Specificity Multidrug Efflux Pump Requiring a Pair of Homologous SMR-Type Proteins

2000 ◽  
Vol 182 (8) ◽  
pp. 2311-2313 ◽  
Author(s):  
Donald L. Jack ◽  
Michael L. Storms ◽  
Jason H. Tchieu ◽  
Ian T. Paulsen ◽  
Milton H. Saier
Keyword(s):  
Escherichia Coli ◽  
Efflux Pump ◽  
Multidrug Resistant ◽  
Drug Efflux ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Resistant Phenotype ◽  
Small Multidrug Resistance ◽  
Drug Efflux Pumps ◽  
Broad Specificity

ABSTRACT The Bacillus subtilis genome encodes seven homologues of the small multidrug resistance (SMR) family of drug efflux pumps. Six of these homologues are paired in three distinct operons, and coexpression in Escherichia coli of one such operon,ykkCD, but not expression of either ykkC orykkD alone, gives rise to a broad specificity, multidrug-resistant phenotype including resistance to cationic, anionic, and neutral drugs.

scholarly journals EfrAB, an ABC Multidrug Efflux Pump in Enterococcus faecalis

2003 ◽  
Vol 47 (12) ◽  
pp. 3733-3738 ◽  
Author(s):  
Eun-Woo Lee ◽  
M. Nazmul Huda ◽  
Teruo Kuroda ◽  
Tohru Mizushima ◽  
Tomofusa Tsuchiya
Keyword(s):  
Enterococcus Faecalis ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Amino Acid Sequences ◽  
Open Reading Frames ◽  
Multidrug Efflux ◽  
Chromosomal Dna ◽  
Multidrug Efflux Pump ◽  
E Coli ◽  
Dna Fragment

ABSTRACT A DNA fragment responsible for resistance to antimicrobial agents was cloned from the chromosomal DNA of Enterococcus faecalis ATCC 29212 by using drug-hypersensitive mutant Escherichia coli KAM32 as a host cell. Cells of E. coli KAM32 harboring a recombinant plasmid (pAEF82) carrying the DNA fragment became resistant to many structurally unrelated antimicrobial agents, such as norfloxacin, ciprofloxacin, doxycycline, acriflavine, 4′,6-diamidino-2-phenylindole, tetraphenylphosphonium chloride, daunorubicin, and doxorubicin. Since the sequence of the whole genome of E. faecalis is known, we sequenced several portions of the DNA insert in plasmid pAEF82 and identified two open reading frames within the insert. We designated the genes efrA and efrB. A search of the deduced amino acid sequences of EfrA and EfrB revealed that they are similar to each other and that they belong to the ATP-binding cassette (ABC) family of multidrug efflux transporters. Transformed E. coli KAM32 cells harboring efrAB showed energy-dependent efflux of acriflavine. The efflux activity was inhibited by reserpine, verapamil, and sodium-o-vanadate, known inhibitors of ABC efflux pumps.

scholarly journals Control of Biofilm Formation in Healthcare: Recent Advances Exploiting Quorum-Sensing Interference Strategies and Multidrug Efflux Pump Inhibitors

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1676 ◽  
Author(s):  
Bindu Subhadra ◽  
Dong Kim ◽  
Kyungho Woo ◽  
Surya Surendran ◽  
Chul Choi
Keyword(s):  
Quorum Sensing ◽  
Biofilm Formation ◽  
Efflux Pump ◽  
Financial Burden ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Persistent Infections ◽  
Healthcare Settings ◽  
Recent Advances ◽  
Multidrug Efflux Pumps

Biofilm formation in healthcare is an issue of considerable concern, as it results in increased morbidity and mortality, imposing a significant financial burden on the healthcare system. Biofilms are highly resistant to conventional antimicrobial therapies and lead to persistent infections. Hence, there is a high demand for novel strategies other than conventional antibiotic therapies to control biofilm-based infections. There are two approaches which have been employed so far to control biofilm formation in healthcare settings: one is the development of biofilm inhibitors based on the understanding of the molecular mechanism of biofilm formation, and the other is to modify the biomaterials which are used in medical devices to prevent biofilm formation. This review will focus on the recent advances in anti-biofilm approaches by interrupting the quorum-sensing cellular communication system and the multidrug efflux pumps which play an important role in biofilm formation. Research efforts directed towards these promising strategies could eventually lead to the development of better anti-biofilm therapies than the conventional treatments.

scholarly journals Dehydrozingerone Exhibits Synergistic Antifungal Activities in Combination with Dodecanol against Budding Yeast via the Restriction of Multidrug Resistance

2018 ◽  
Vol 5 (02) ◽  
pp. e61-e67
Author(s):  
Chika Yamawaki ◽  
Yoshihiro Yamaguchi ◽  
Akira Ogita ◽  
Toshio Tanaka ◽  
Ken-ichi Fujita
Keyword(s):  
Drug Resistance ◽  
Antifungal Activity ◽  
Efflux Pump ◽  
Fungal Infections ◽  
Zingiber Officinale ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Yeast Saccharomyces Cerevisiae ◽  
Multidrug Transporters ◽  
Multidrug Efflux Pumps

AbstractDrug resistance in fungal infections has been a more frequent occurrence with the increasing number of immunocompromised patients. In efforts to overcome the problem of fungal drug resistance, we focused on the phenolic compound dehydrozingerone, which is isolated from Zingiber officinale. The effectiveness of this compound on the model yeast Saccharomyces cerevisiae has not been reported. In our study, dehydrozingerone showed a weak antifungal activity against the yeast, but demonstrated a synergistic effect in combination with dodecanol, which typically only restricts cell growth transiently. Efflux of rhodamine 6G through the multidrug efflux pumps was significantly restricted by dehydrozingerone. The transcription level of PDR5, encoding a primary multidrug efflux pump in S. cerevisiae, was enhanced with dodecanol treatment, whereas the level was reduced by dehydrozingerone. These results suggest that dehydrozingerone may be effective for potentiating antifungal activity of other drugs that are expelled from fungi by multidrug transporters like Pdr5p.

scholarly journals SmdAB, a Heterodimeric ABC-Type Multidrug Efflux Pump, in Serratia marcescens

2007 ◽  
Vol 190 (2) ◽  
pp. 648-654 ◽  
Author(s):  
Taira Matsuo ◽  
Jing Chen ◽  
Yusuke Minato ◽  
Wakano Ogawa ◽  
Tohru Mizushima ◽  
...  
Keyword(s):  
Serratia Marcescens ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Amino Acid Sequences ◽  
Multidrug Efflux ◽  
Chromosomal Dna ◽  
Atpase Inhibitor ◽  
Multidrug Efflux Pump ◽  
Hoechst 33342 ◽  
E Coli

ABSTRACT We cloned genes, designated smdAB, that encode a multidrug efflux pump from the chromosomal DNA of clinically isolated Serratia marcescens NUSM8906. For cells of the drug-hypersensitive strain Escherichia coli KAM32 harboring a recombinant plasmid carrying smdAB, structurally unrelated antimicrobial agents such as norfloxacin, tetracycline, 4′,6-diamidino-2-phenylindole (DAPI), and Hoechst 33342 showed elevated MICs. The deduced amino acid sequences of both SmdA and SmdB exhibited similarities to the sequences of ATP-binding cassette (ABC)-type multidrug efflux pumps. The efflux of DAPI and Hoechst 33342 from E. coli cells expressing SmdAB was observed, and the efflux activities were inhibited by sodium o-vanadate, which is a well-known ATPase inhibitor. The introduction of smdA or smdB alone into E. coli KAM32 did not elevate the MIC of DAPI; thus, both SmdA and SmdB were required for function. These results indicate that SmdAB is probably a heterodimeric multidrug efflux pump of the ABC family in S. marcescens.

scholarly journals Multiresistance Genes of Rhizobium etli CFN42

2000 ◽  
Vol 13 (5) ◽  
pp. 572-577 ◽  
Author(s):  
Ramón González-Pasayo ◽  
Esperanza Martínez-Romero
Keyword(s):  
Wild Type Strain ◽  
Efflux Pump ◽  
Rhizobium Etli ◽  
Wild Type ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Enhanced Sensitivity ◽  
Multidrug Efflux Pumps ◽  
High Concentrations ◽  
Major Facilitator

Multidrug efflux pumps of bacteria are involved in the resistance to various antibiotics and toxic compounds. In Rhizobium etli, a mutualistic symbiont of Phaseolus vulgaris (bean), genes resembling multidrug efflux pump genes were identified and designated rmrA and rmrB. rmrA was obtained after the screening of transposon-generated fusions that are inducible by bean-root released flavonoids. The predicted gene products of rmrAB shared significant homology to membrane fusion and major facilitator proteins, respectively. Mutants of rmrA formed on average 40% less nodules in bean, while mutants of rmrA and rmrB had enhanced sensitivity to phytoalexins, flavonoids, and salicylic acid, compared with the wild-type strain. Multidrug resistance genes emrAB from Escherichia coli complemented an rmrA mutant from R. etli for resistance to high concentrations of naringenin.

scholarly journals NorM of Vibrio parahaemolyticus Is an Na+-Driven Multidrug Efflux Pump

2000 ◽  
Vol 182 (23) ◽  
pp. 6694-6697 ◽  
Author(s):  
Yuji Morita ◽  
Atsuko Kataoka ◽  
Sumiko Shiota ◽  
Tohru Mizushima ◽  
Tomofusa Tsuchiya
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Efflux Pump ◽  
Sequence Similarity ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Significant Sequence Similarity ◽  
Wide Range ◽  
New Type ◽  
Biological World ◽  
Energy Dependent

ABSTRACT NorM of Vibrio parahaemolyticusapparently is a new type of multidrug efflux protein, with no significant sequence similarity to any known transport proteins. Based on the following experimental results, we conclude that NorM is an Na+-driven Na+/drug antiporter. (i) Energy-dependent ethidium efflux from cells possessing NorM was observed in the presence of Na+ but not of K+. (ii) An artificially imposed, inwardly directed Na+gradient elicited ethidium efflux from cells. (iii) The addition of ethidium to cells loaded with Na+ elicited Na+efflux. Thus, NorM is an Na+/drug antiporting multidrug efflux pump, the first to be found in the biological world. Judging from the similarity of the NorM sequence to those of putative proteins in sequence databases, it seems that Na+/drug antiporters are present not only in V. parahaemolyticus but also in a wide range of other organisms.

scholarly journals CmeABC Functions as a Multidrug Efflux System in Campylobacter jejuni

2002 ◽  
Vol 46 (7) ◽  
pp. 2124-2131 ◽  
Author(s):  
Jun Lin ◽  
Linda Overbye Michel ◽  
Qijing Zhang
Keyword(s):  
Campylobacter Jejuni ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Wild Type ◽  
Multidrug Efflux ◽  
Intrinsic Resistance ◽  
Multidrug Efflux Pump ◽  
Efflux Pump Inhibitor ◽  
Gram Negative ◽  
Multidrug Efflux Pumps

ABSTRACT Campylobacter jejuni, a gram-negative organism causing gastroenteritis in humans, is increasingly resistant to antibiotics. However, little is known about the drug efflux mechanisms in this pathogen. Here we characterized an efflux pump encoded by a three-gene operon (designated cmeABC) that contributes to multidrug resistance in C. jejuni 81-176. CmeABC shares significant sequence and structural homology with known tripartite multidrug efflux pumps in other gram-negative bacteria, and it consists of a periplasmic fusion protein (CmeA), an inner membrane efflux transporter belonging to the resistance-nodulation-cell division superfamily (CmeB), and an outer membrane protein (CmeC). Immunoblotting using CmeABC-specific antibodies demonstrated that cmeABC was expressed in wild-type 81-176; however, an isogenic mutant (9B6) with a transposon insertion in the cmeB gene showed impaired production of CmeB and CmeC. Compared to wild-type 81-176, 9B6 showed a 2- to 4,000-fold decrease in resistance to a range of antibiotics, heavy metals, bile salts, and other antimicrobial agents. Accumulation assays demonstrated that significantly more ethidium bromide and ciprofloxacin accumulated in mutant 9B6 than in wild-type 81-176. Addition of carbonyl cyanide m-chlorophenylhydrazone, an efflux pump inhibitor, increased the accumulation of ciprofloxacin in wild-type 81-176 to the level of mutant 9B6. PCR and immunoblotting analysis also showed that cmeABC was broadly distributed in various C. jejuni isolates and constitutively expressed in wild-type strains. Together, these findings formally establish that CmeABC functions as a tripartite multidrug efflux pump that contributes to the intrinsic resistance of C. jejuni to a broad range of structurally unrelated antimicrobial agents.

scholarly journals Molecular Cloning and Characterization of an ABC Multidrug Efflux Pump, VcaM, in Non-O1 Vibrio cholerae

2003 ◽  
Vol 47 (8) ◽  
pp. 2413-2417 ◽  
Author(s):  
Nazmul Huda ◽  
Eun-Woo Lee ◽  
Jing Chen ◽  
Yuji Morita ◽  
Teruo Kuroda ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Vibrio Cholerae ◽  
Efflux Pump ◽  
Efflux Pumps ◽  
Atp Binding ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Hoechst 33342 ◽  
Hydrophobic Domain ◽  
Multidrug Efflux Pumps

ABSTRACT 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 multidrug efflux pumps. E. coli cells transformed with the gene showed elevated levels of resistance to a number of structurally dissimilar drugs, such as tetracycline, norfloxacin, ciprofloxacin, doxorubicin, daunomycin, 4′,6-diamidino-2-phenylindole, and Hoechst 33342. We determined the nucleotide sequence and found one open reading frame. We designated the gene vcaM. The deduced product, VcaM, seems to be a polypeptide with 619 amino acid residues (69 kDa) that has a putative topology of six transmembrane segments in the N-terminal hydrophobic domain, followed by an ATP binding domain in the C-terminal hydrophilic region. The sequence of VcaM was shown to be similar to those of human multidrug resistance proteins P-glycoprotein MDR1 and lactococcal LmrA, which are driven by ATP. The efflux of Hoechst 33342 and doxorubicin from cells possessing VcaM was detected. The efflux activity was inhibited by reserpine and sodium o-vanadate, which are potent inhibitors of MDR1 and LmrA. Thus, we conclude that VcaM is a member of the family of multidrug efflux pumps of the ATP binding cassette type and the first experimentally proven example of a multidrug efflux pump of this family in gram-negative bacteria.

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