Molecular modelling and simulation studies of the Mycobacterium tuberculosis multidrug efflux pump protein Rv1258c

In the search for an effective strategy to overcome antimicrobial resistance, a series of new morpholine-containing 5-arylideneimidazolones differing within either the amine moiety or at position five of imidazolones was explored as potential antibiotic adjuvants against Gram-positive and Gram-negative bacteria. Compounds (7–23) were tested for oxacillin adjuvant properties in the Methicillin-susceptible S. aureus (MSSA) strain ATCC 25923 and Methicillin-resistant S. aureus MRSA 19449. Compounds 14–16 were tested additionally in combination with various antibiotics. Molecular modelling was performed to assess potential mechanism of action. Microdilution and real-time efflux (RTE) assays were carried out in strains of K. aerogenes to determine the potential of compounds 7–23 to block the multidrug efflux pump AcrAB-TolC. Drug-like properties were determined experimentally. Two compounds (10, 15) containing non-condensed aromatic rings, significantly reduced oxacillin MICs in MRSA 19449, while 15 additionally enhanced the effectiveness of ampicillin. Results of molecular modelling confirmed the interaction with the allosteric site of PBP2a as a probable MDR-reversing mechanism. In RTE, the compounds inhibited AcrAB-TolC even to 90% (19). The 4-phenylbenzylidene derivative (15) demonstrated significant MDR-reversal “dual action” for β-lactam antibiotics in MRSA and inhibited AcrAB-TolC in K. aerogenes. 15 displayed also satisfied solubility and safety towards CYP3A4 in vitro.

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Piperine as an inhibitor of Rv1258c, a putative multidrug efflux pump of Mycobacterium tuberculosis

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkq186 ◽

2010 ◽

Vol 65 (8) ◽

pp. 1694-1701 ◽

Cited By ~ 93

Author(s):

S. Sharma ◽

M. Kumar ◽

S. Sharma ◽

A. Nargotra ◽

S. Koul ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Efflux Pump ◽

Multidrug Efflux ◽

Multidrug Efflux Pump

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Identification of a Novel Multidrug Efflux Pump of Mycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00298-08 ◽

2008 ◽

Vol 52 (7) ◽

pp. 2503-2511 ◽

Cited By ~ 89

Author(s):

Olga Danilchanka ◽

Claudia Mailaender ◽

Michael Niederweis

Keyword(s):

Mycobacterium Tuberculosis ◽

Outer Membrane ◽

Bacterial Infections ◽

Molecular Mechanisms ◽

Efflux Pump ◽

Model Organism ◽

Multidrug Efflux ◽

Multidrug Efflux Pump ◽

Efflux Pump Inhibitor ◽

High Level

ABSTRACT The impermeability of the outer membrane in combination with drug efflux are major determinants of the natural drug resistance of mycobacteria. β-Lactams are the most widely used antibiotics for treatment of bacterial infections. However, it is unknown how β-lactams enter Mycobacterium tuberculosis and whether efflux pumps exist that can export these drugs out of the cell. To identify the molecular mechanisms of M. tuberculosis resistance to β-lactams, a library of 7,500 transposon mutants was generated in the model organism Mycobacterium bovis BCG. Thirty-three unique insertion sites were determined that conferred medium or high-level (≥2,000 μg/ml) resistance to ampicillin. Three mutants in sulfolipid synthesis or transport were highly resistant to ampicillin, indicating an indirect effect of the lipid composition on the outer membrane permeability of M. bovis BCG to ampicillin. Mutants with insertions in genes encoding surface molecules such as PPE proteins or lipoarabinomannan were also completely resistant to ampicillin, thus suggesting a lack of transport across the outer membrane. Insertion of the transposon in front of bcg0231 increased transcription of the gene and concomitantly the resistance of M. bovis BCG to ampicillin, streptomycin, and chloramphenicol by 32- to 64-fold. Resistance to vancomycin and tetracycline was increased four- to eightfold. Bcg0231 and Rv0194 are almost identical ATP-binding cassette transporters. Expression of rv0194 significantly reduced accumulation of ethidium bromide and conferred multidrug resistance to Mycobacterium smegmatis. Both effects were abrogated in the presence of the efflux pump inhibitor reserpine. These results demonstrate that Rv0194 is a novel multidrug efflux pump of M. tuberculosis.

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Characterization of P55, a Multidrug Efflux Pump inMycobacterium bovis and Mycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.45.3.800-804.2001 ◽

2001 ◽

Vol 45 (3) ◽

pp. 800-804 ◽

Cited By ~ 82

Author(s):

Pedro E. A. Silva ◽

Fabiana Bigi ◽

Marı́a de la Paz Santangelo ◽

Maria Isabel Romano ◽

Carlos Martı́n ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Mycobacterium Smegmatis ◽

Efflux Pump ◽

Tetracycline Resistance ◽

Drug Efflux ◽

Multidrug Efflux ◽

Multidrug Efflux Pump ◽

Reading Frame ◽

Carbonyl Cyanide

ABSTRACT The Mycobacterium bovis P55 gene, located downstream from the gene that encodes the immunogenic lipoprotein P27, has been characterized. The gene was identical to the open reading frame of the Rv1410c gene in the genome of Mycobacterium tuberculosisH37Rv, annotated as a probable drug efflux protein. Genes similar toP55 were present in all species of the M. tuberculosis complex and other mycobacteria such asMycobacterium leprae and Mycobacterium avium. By Western blotting, P55 was located in the membrane fraction ofM. bovis. When transformed into Mycobacterium smegmatis after cloning, P55 conferred aminoglycoside and tetracycline resistance. The levels of resistance to streptomycin and tetracycline conferred by P55 were decreased in the presence of the protonophore carbonyl cyanide m-chlorophenylhydrazone and the pump inhibitors verapamil and reserpine. M. smegmatiscells expressing the plasmid-encoded P55 accumulated less tetracycline than the control cells. We conclude that P55 is a membrane protein implicated in aminoglycoside and tetracycline efflux in mycobacteria.

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Faculty Opinions recommendation of Structure of the AcrAB-TolC multidrug efflux pump.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718356663.793495679 ◽

2014 ◽

Author(s):

Paul Savage

Keyword(s):

Efflux Pump ◽

Multidrug Efflux ◽

Multidrug Efflux Pump

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Faculty Opinions recommendation of Molecular basis for inhibition of AcrB multidrug efflux pump by novel and powerful pyranopyridine derivatives.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726218324.793516072 ◽

2016 ◽

Author(s):

Herschel Wade

Keyword(s):

Molecular Basis ◽

Efflux Pump ◽

Multidrug Efflux ◽

Multidrug Efflux Pump

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Faculty Opinions recommendation of Biased partitioning of the multidrug efflux pump AcrAB-TolC underlies long-lived phenotypic heterogeneity.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727537002.793532571 ◽

2017 ◽

Author(s):

Chris Whitfield

Keyword(s):

Efflux Pump ◽

Phenotypic Heterogeneity ◽

Multidrug Efflux ◽

Multidrug Efflux Pump

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Correlation between the Antibiotic Resistance Genes and Susceptibility to Antibiotics among the Carbapenem-Resistant Gram-Negative Pathogens

Antibiotics ◽

10.3390/antibiotics10030255 ◽

2021 ◽

Vol 10 (3) ◽

pp. 255

Author(s):

Salma M. Abdelaziz ◽

Khaled M. Aboshanab ◽

Ibrahim S. Yahia ◽

Mahmoud A. Yassien ◽

Nadia A. Hassouna

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Efflux Pump ◽

Antibiotic Resistance Genes ◽

Multiple Drug ◽

P Value ◽

Multidrug Efflux ◽

Multidrug Efflux Pump ◽

Gram Negative ◽

Carbapenem Resistant

In this study, the correlation between the antibiotic resistance genes and antibiotic susceptibility among the carbapenem-resistant Gram-negative pathogens (CRGNPs) recovered from patients diagnosed with acute pneumonia in Egypt was found. A total of 194 isolates including Klebsiella pneumoniae (89; 46%), Escherichia coli (47; 24%) and Pseudomonas aeruginosa (58; 30%) were recovered. Of these, 34 (18%) isolates were multiple drug resistant (MDR) and carbapenem resistant. For the K. pneumoniae MDR isolates (n = 22), blaNDM (14; 64%) was the most prevalent carbapenemase, followed by blaOXA-48 (11; 50%) and blaVIM (4; 18%). A significant association (p value < 0.05) was observed between the multidrug efflux pump (AcrA) and resistance to β-lactams and the aminoglycoside acetyl transferase gene (aac-6’-Ib) gene and resistance to ciprofloxacin, azithromycin and β-lactams (except for aztreonam). For P. aeruginosa, a significant association was noticed between the presence of the blaSHV gene and the multidrug efflux pump (MexA) and resistance to fluoroquinolones, amikacin, tobramycin, co-trimoxazole and β-lactams and between the aac-6’-Ib gene and resistance to aminoglycosides. All P. aeruginosa isolates (100%) harbored the MexAB-OprM multidrug efflux pump while 86% of the K. pneumoniae isolates harbored the AcrAB-TolC pump. Our results are of great medical importance for the guidance of healthcare practitioners for effective antibiotic prescription.

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