The Role Of Mexxy Efflux Pump Expression In The Development Of Aminoglycoside Resistance In P. Aeruginosa Over Time In Patients With Cystic Fibrosis

AbstractThe biological features that allow a pathogen to survive in the hospital environment are mostly unknown. The extinction of bacterial epidemics in hospitals is mostly attributed to changes in medical practice, including infection control, but the role of bacterial adaptation has never been documented. We analyzed a collection of Pseudomonas aeruginosa isolates belonging to the Besançon Epidemic Strain (BES), responsible for a 12-year nosocomial outbreak, using a genotype-to-phenotype approach. Bayesian analysis estimated the emergence of the clone in the hospital five years before its opening, during the creation of its water distribution network made of copper. BES survived better than the reference strains PAO1 and PA14 in a copper solution due to a genomic island containing 13 metal-resistance genes and was specifically able to proliferate in the ubiquitous amoeba Vermamoeba vermiformis. Mutations affecting amino-acid metabolism, antibiotic resistance, lipopolysaccharide biosynthesis, and regulation were enriched during the spread of BES. Seven distinct regulatory mutations attenuated the overexpression of the genes encoding the efflux pump MexAB-OprM over time. The fitness of BES decreased over time in correlation with its genome size. Overall, the resistance to inhibitors and predators presumably aided the proliferation and propagation of BES in the plumbing system of the hospital. The pathogen further spread among patients via multiple routes of contamination. The decreased prevalence of patients infected by BES mirrored the parallel and convergent genomic evolution and reduction that affected bacterial fitness. Along with infection control measures, this may have participated in the extinction of BES in the hospital setting.ImportanceBacterial pathogens are responsible for nosocomial outbreaks, but the sources of contamination of the hospitals are mostly unclear and the role of bacterial evolution in the extinction of outbreaks has never been considered. Here, we found that an epidemic strain of the pathogen Pseudomonas aeruginosa contaminated the drinking water network of a hospital due to its tolerance to copper and predatory amoeba, both present in the water pipes. The extinction of the outbreak occurred concomitantly with parallel and convergent genome evolution and a reduction in the size of the bacterial genome that correlated with the fitness of the pathogen. Our data suggest that pathogen evolution participated in the extinction of an outbreak in a hospital setting.

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Mutations in Ribosomal Protein RplA or Treatment with Ribosomal Acting Antibiotics Activates Production of Aminoglycoside Efflux Pump SmeYZ in Stenotrophomonas maltophilia

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01524-19 ◽

2019 ◽

Vol 64 (2) ◽

Cited By ~ 1

Author(s):

Karina Calvopiña ◽

Punyawee Dulyayangkul ◽

Matthew B. Avison

Keyword(s):

Ribosomal Protein ◽

Stenotrophomonas Maltophilia ◽

Efflux Pump ◽

Clinical Isolates ◽

Efflux System ◽

Aminoglycoside Resistance ◽

Content Type ◽

Ribosomal Protein L1 ◽

Significant Mechanism

ABSTRACT Aminoglycoside resistance in Stenotrophomonas maltophilia is multifactorial, but the most significant mechanism is overproduction of the SmeYZ efflux system. By studying laboratory-selected mutants and clinical isolates, we show here that damage to the 50S ribosomal protein L1 (RplA) activates SmeYZ production. We also show that gentamicin and minocycline, which target the ribosome, induce expression of smeYZ. These findings explain the role of SmeYZ in both intrinsic and mutationally acquired aminoglycoside resistance.

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Pseudomonas aeruginosa Biofilm Lung Infection in Cystic Fibrosis: The Challenge of Persisters

10.5772/intechopen.95590 ◽

2021 ◽

Author(s):

Gianmarco Mangiaterra ◽

Mehdi Amiri ◽

Nicholas Cedraro ◽

Francesca Biavasco

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Efflux Pump ◽

Low Frequency ◽

Lung Infection ◽

Resistant Strains ◽

Special Concern ◽

Microbiological Assays ◽

Acquired Antibiotic Resistance

Pseudomonas aeruginosa lung infection is difficult to eradicate due to the multiple (intrinsic and acquired) antibiotic resistance of bacteria and to their ability to produce a thick biofilm. Antibiotic treatment is hampered by poor antibiotic diffusion, efflux pump overexpression and the development of a persistent subpopulation with low metabolic activity. This is a cause for special concern in Cystic Fibrosis (CF) patients, where P. aeruginosa lung infection is the chief cause of morbidity and mortality. Combined tobramycin-ciprofloxacin treatment is routinely adopted due to the low frequency of resistant strains and its ostensible ability to control the infection. Nevertheless, symptoms usually recur, mainly due to the antibiotic persisters, which are difficult to detect in routine cultural microbiological assays. This chapter describes the issues involved in the microbiological diagnosis of P. aeruginosa lung infection in CF patients and the possible role of subinhibitory antibiotic concentrations in persister development and infection recurrence.

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MexXY efflux pump overexpression and aminoglycoside resistance in cystic fibrosis isolates of Pseudomonas aeruginosa from chronic infections

Canadian Journal of Microbiology ◽

10.1139/cjm-2017-0380 ◽

2017 ◽

Vol 63 (12) ◽

pp. 929-938 ◽

Cited By ~ 8

Author(s):

Manu Singh ◽

Yvonne C.W. Yau ◽

Shirley Wang ◽

Valerie Waters ◽

Ayush Kumar

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Efflux Pump ◽

Multidrug Resistant ◽

Regulatory Genes ◽

Multidrug Efflux ◽

Chronic Infections ◽

Aminoglycoside Resistance ◽

Resistance Nodulation Division ◽

Lung Infections

In this study, we analyzed 15 multidrug-resistant cystic fibrosis isolates of Pseudomonas aeruginosa from chronic lung infections for expression of 4 different multidrug efflux systems (MexAB–OprM, MexCD–OprJ, MexEF–OprN, and MexXY), using quantitative reverse transcriptase PCR. Overexpression of MexXY pump was observed in all of the isolates tested. Analysis of regulatory genes that control the expression of these 4 efflux pumps revealed a number of previously uncharacterized mutations. Our work shows that MexXY pump overexpression is common in cystic fibrosis isolates and could be contributing to their reduced aminoglycoside susceptibility. Further, we also identified novel mutations in the regulatory genes of the 4 abovementioned Resistance–Nodulation–Division superfamily pumps that may be involved in the overexpression of these pumps.

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The BpeAB-OprB Efflux Pump of Burkholderia pseudomallei 1026b Does Not Play a Role in Quorum Sensing, Virulence Factor Production, or Extrusion of Aminoglycosides but Is a Broad-Spectrum Drug Efflux System

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01803-09 ◽

2010 ◽

Vol 54 (8) ◽

pp. 3113-3120 ◽

Cited By ~ 69

Author(s):

Takehiko Mima ◽

Herbert P. Schweizer

Keyword(s):

Quorum Sensing ◽

Virulence Factor ◽

Burkholderia Pseudomallei ◽

Efflux Pump ◽

Homoserine Lactone ◽

Genetically Engineered ◽

Multidrug Efflux ◽

Efflux System ◽

Aminoglycoside Resistance

ABSTRACT Most Burkholderia pseudomallei strains are intrinsically aminoglycoside resistant, mainly due to AmrAB-OprA-mediated efflux. Rare naturally occurring or genetically engineered mutants lacking this pump are aminoglycoside susceptible despite the fact that they also encode and express BpeAB-OprB, which was reported to mediate efflux of aminoglycosides in the Singapore strain KHW. To reassess the role of BpeAB-OprB in B. pseudomallei aminoglycoside resistance, we used mutants overexpressing or lacking this pump in either AmrAB-OprA-proficient or -deficient strain 1026b backgrounds. Our data show that BpeAB-OprB does not mediate efflux of aminoglycosides but is a multidrug efflux system which extrudes macrolides, fluoroquinolones, tetracyclines, acriflavine, and, to a lesser extent, chloramphenicol. Phylogenetically, BpeAB-OprB is closely related to Pseudomonas aeruginosa MexAB-OprM, which has a similar substrate spectrum. AmrAB-OprA is most closely related to MexXY, the only P. aeruginosa efflux pump known to extrude aminoglycosides. Since BpeAB-OprB in strain KHW was also implicated in playing a major role in export of acylated homoserine lactone (AHL) quorum-sensing molecules and in expression of diverse virulence factors, we explored whether this was also true in the strain 1026b background. The results showed that BpeAB-OprB was not required for AHL export, and mutants lacking this efflux system exhibited normal swimming motility and siderophore production, which were severely impaired in KHW bpeAB-oprB mutants. Biofilm formation was impaired in 1026b Δ(amrRAB-oprA) and Δ(amrRAB-oprA) Δ(bpeAB-oprB) mutants. At present, we do not know why our BpeAB-OprB susceptibility and virulence factor expression results with 1026b and its derivatives are different from those previously published for Singapore strain KHW.

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Aminoglycoside resistance mechanisms in Pseudomonas aeruginosa isolates from non-cystic fibrosis patients in Thailand

Canadian Journal of Microbiology ◽

10.1139/cjm-2012-0465 ◽

2013 ◽

Vol 59 (1) ◽

pp. 51-56 ◽

Cited By ~ 6

Author(s):

Kanchana Poonsuk ◽

Chanwit Tribuddharat ◽

Rungtip Chuanchuen

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Amino Acid ◽

High Resistance ◽

Amino Acid Change ◽

Efflux Pump ◽

Resistance Mechanisms ◽

Aminoglycoside Resistance ◽

Resistance Rates

This study aimed to examine aminoglycosides (AMGs) resistance mechanisms, including the AMG-modifying enzyme genes, mexXY, rplY, nuoG, and galU, in the Pseudomonas aeruginosa non-cystic fibrosis (CF) isolates in Thailand. One hundred P. aeruginosa isolates from non-CF patients were examined for susceptibility to AMGs and for the presence of 10 AMG-modifying enzyme genes. Thirty randomly selected isolates were tested for transcription of mexXY and nuoG and mutations in rplY and galU. All the P. aeruginosa isolates exhibited simultaneous resistance to at least 4 AMGs. High resistance rates to amikacin (92%), gentamicin (95%), streptomycin (99%), and tobramycin (96%) were observed, and all isolates were resistant to kanamycin, neomycin, and spectinomycin. Nine AMG-modifying enzyme genes were detected, including aadA1 (84%), aadB (84%), aadA2 (67%), ant(2″)-Ia (72%), strA-strB (70%), aph(3′)-IIb (57%), aac(3′)-Ia (40%), and aac(6′)-IIa (27%). None of the isolates harbored aac(6′)-IIb. Of 30 isolates tested, all but 1 isolate expressed MexXY. Two isolates did not express nuoG. Six isolates carried an amino acid change in RplY, but none of the isolates harbored mutation in galU. The results indicated that the AMG-modifying enzyme genes were widespread among the P. aeruginosa non-CF isolates. The MexXY efflux pump and inactivation for rplY played a role in AMG resistance but disruption of nuoG or galU did not.

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Role of RND Efflux Pumps in Drug Resistance of Cystic Fibrosis Pathogens

Antibiotics ◽

10.3390/antibiotics10070863 ◽

2021 ◽

Vol 10 (7) ◽

pp. 863

Author(s):

Viola Camilla Scoffone ◽

Gabriele Trespidi ◽

Giulia Barbieri ◽

Samuele Irudal ◽

Elena Perrin ◽

...

Keyword(s):

Cystic Fibrosis ◽

Drug Resistance ◽

Efflux Pump ◽

Bacterial Species ◽

Efflux Pumps ◽

Burkholderia Cenocepacia ◽

Multi Drug Resistance ◽

Achromobacter Xylosoxidans ◽

Rnd Efflux Pumps

Drug resistance represents a great concern among people with cystic fibrosis (CF), due to the recurrent and prolonged antibiotic therapy they should often undergo. Among Multi Drug Resistance (MDR) determinants, Resistance-Nodulation-cell Division (RND) efflux pumps have been reported as the main contributors, due to their ability to extrude a wide variety of molecules out of the bacterial cell. In this review, we summarize the principal RND efflux pump families described in CF pathogens, focusing on the main Gram-negative bacterial species (Pseudomonas aeruginosa, Burkholderia cenocepacia, Achromobacter xylosoxidans, Stenotrophomonas maltophilia) for which a predominant role of RND pumps has been associated to MDR phenotypes.

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