efflux pumps
- Mechanisms of ResistanceNovel Mechanisms of Efflux-Mediated Levofloxacin Resistance and Reduced Amikacin Susceptibility in Stenotrophomonas maltophilia
Fluoroquinolone resistance in Stenotrophomonas maltophilia is multifactorial, but the most significant factor is overproduction of efflux pumps, particularly SmeDEF, following mutation. Here, we report that mutations in the glycosyl transferase gene smlt0622 in S. maltophilia K279a mutant K...
- Mechanisms of ResistanceAntibiotic Substrate Selectivity of Pseudomonas aeruginosa MexY and MexB Efflux Systems Is Determined by a Goldilocks Affinity
Resistance-nodulation-division (RND) efflux pumps are important contributors to bacterial antibiotic resistance. In this study, we combined evolutionary sequence analyses, computational structural modeling, and ligand docking to develop a framework that can explain the known antibiotic substrate selectivity differences between two Pseudomonas aeruginosa RND...
- SusceptibilityThioridazine Is an Efflux Pump Inhibitor in Mycobacterium avium Complex but of Limited Clinical Relevance
Treatment of Mycobacterium avium complex pulmonary disease (MAC-PD) is challenging partly due to high efflux pump expression. Thioridazine might block these efflux pumps. We explore the efficacy of thioridazine against M. avium isolates using MICs, time-kill combination assays, ex vivo...
- Mechanisms of Action: Physiological EffectsPossible Binding of Piperine in Mycobacterium tuberculosis RNA Polymerase and Rifampin Synergism
The activity of rifampin (RIF) and piperine was evaluated at the relative transcript levels of 12 efflux pumps (EPs), and an additional mechanism was proposed to be behind the synergic interactions of piperine plus RIF in Mycobacterium tuberculosis. AutoDock v4.2.3 and Molegro v6 programs were used to evaluate PIP binding in...
- Mechanisms of ResistanceCinnamaldehyde Induces Expression of Efflux Pumps and Multidrug Resistance in Pseudomonas aeruginosa
Essential oils or their components are increasingly used to fight bacterial infections. Cinnamaldehyde (CNA), the main constituent of cinnamon bark oil, has demonstrated interesting properties in vitro against various pathogens, including Pseudomonas aeruginosa. In the present study, we investigated the mechanisms and possible therapeutic consequences of...
- Mechanisms of ResistanceThe TetR Family Transcription Factor MAB_2299c Regulates the Expression of Two Distinct MmpS-MmpL Efflux Pumps Involved in Cross-Resistance to Clofazimine and Bedaquiline in Mycobacterium abscessus
Mycobacterium abscessus is a human pathogen responsible for severe respiratory infections, particularly in patients with underlying lung disorders. Notorious for being highly resistant to most antimicrobials, new therapeutic approaches are needed to successfully treat M. abscessus-infected patients...
- Mechanisms of ResistanceAbrogation of Triazole Resistance upon Deletion of CDR1 in a Clinical Isolate of Candida auris
Candida auris has rapidly emerged as a health care-associated and multidrug-resistant pathogen of global concern. In this work, we examined the relative expression of the four C. auris genes with the highest degree of homology to Candida...
- SusceptibilityHigh Prevalence of Bedaquiline Resistance in Treatment-Naive Tuberculosis Patients and Verapamil Effectiveness
In the regions where bedaquiline (BDQ) is introduced into the regimen, analysis of MIC and screening for preexisting resistance mutations could be crucial. The high prevalence of isolates with high BDQ MICs without prior exposure to BDQ was worrisome.
- Mechanisms of ResistanceRoles of Efflux Pumps from Different Superfamilies in the Surface-Associated Motility and Virulence of Acinetobacter baumannii ATCC 17978
Although the relationship between Acinetobacter baumannii efflux pumps and antimicrobial resistance is well documented, less is known about the involvement of these proteins in the pathogenicity of this nosocomial pathogen. In previous work, we identified the AbaQ major facilitator superfamily (MFS) efflux pump and demonstrated its participation in the motility and...
- Mechanisms of ResistanceTarget (MexB)- and Efflux-Based Mechanisms Decreasing the Effectiveness of the Efflux Pump Inhibitor D13-9001 in Pseudomonas aeruginosa PAO1: Uncovering a New Role for MexMN-OprM in Efflux of β-Lactams and a Novel Regulatory Circuit (MmnRS) Controlling MexMN Expression
Efflux pumps contribute to antibiotic resistance in Gram-negative pathogens. Correspondingly, efflux pump inhibitors (EPIs) may reverse this resistance.