Collateral Sensitivity Associated with Antibiotic Resistance Plasmids

AbstractCollateral sensitivity (CS) is a promising alternative approach to counteract the rising problem of antibiotic resistance (ABR). CS occurs when the acquisition of resistance to one antibiotic produces increased susceptibility to a second antibiotic. For CS to be widely applicable in clinical practice, it would need to be effective against the different resistance mechanisms available to bacteria. Recent studies have focused on CS strategies designed against ABR mediated by chromosomal mutations. However, one of the main drivers of ABR in clinically relevant bacteria is the horizontal transfer of ABR genes mediated by plasmids. Here, we report the first analysis of CS associated with the acquisition of complete ABR plasmids, including the clinically important carbapenem-resistance conjugative plasmid pOXA-48. In addition, we describe the conservation of CS in clinical E. coli isolates and its application to the selective elimination of plasmid-carrying bacteria. Our results provide new insights that establish the basis for developing CS-informed treatment strategies to combat plasmid-mediated ABR.

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Collateral sensitivity associated with antibiotic resistance plasmids

eLife ◽

10.7554/elife.65130 ◽

2021 ◽

Vol 10 ◽

Author(s):

Cristina Herencias ◽

Jerónimo Rodríguez-Beltrán ◽

Ricardo León-Sampedro ◽

Aida Alonso-del Valle ◽

Jana Palkovičová ◽

...

Keyword(s):

Antibiotic Resistance ◽

Treatment Strategies ◽

Carbapenem Resistance ◽

Conjugative Plasmid ◽

Promising Alternative ◽

E Coli ◽

Collateral Sensitivity ◽

Alternative Approach ◽

Informed Treatment ◽

Chromosomal Mutations

Collateral sensitivity (CS) is a promising alternative approach to counteract the rising problem of antibiotic resistance (ABR). CS occurs when the acquisition of resistance to one antibiotic produces increased susceptibility to a second antibiotic. Recent studies have focused on CS strategies designed against ABR mediated by chromosomal mutations. However, one of the main drivers of ABR in clinically relevant bacteria is the horizontal transfer of ABR genes mediated by plasmids. Here, we report the first analysis of CS associated with the acquisition of complete ABR plasmids, including the clinically important carbapenem-resistance conjugative plasmid pOXA-48. In addition, we describe the conservation of CS in clinical E. coli isolates and its application to selectively kill plasmid-carrying bacteria. Our results provide new insights that establish the basis for developing CS-informed treatment strategies to combat plasmid-mediated ABR.

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Nitric oxide (NO) elicits aminoglycoside tolerance in Escherichia coli but antibiotic resistance gene carriage and NO sensitivity have not co-evolved

Archives of Microbiology ◽

10.1007/s00203-021-02245-2 ◽

2021 ◽

Author(s):

Cláudia A. Ribeiro ◽

Luke A. Rahman ◽

Louis G. Holmes ◽

Ayrianna M. Woody ◽

Calum M. Webster ◽

...

Keyword(s):

Nitric Oxide ◽

Antibiotic Resistance ◽

Antibiotic Susceptibility ◽

Bacterial Pathogens ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Resistance Mechanisms ◽

Current Work ◽

E Coli ◽

Respiratory Inhibitor

AbstractThe spread of multidrug-resistance in Gram-negative bacterial pathogens presents a major clinical challenge, and new approaches are required to combat these organisms. Nitric oxide (NO) is a well-known antimicrobial that is produced by the immune system in response to infection, and numerous studies have demonstrated that NO is a respiratory inhibitor with both bacteriostatic and bactericidal properties. However, given that loss of aerobic respiratory complexes is known to diminish antibiotic efficacy, it was hypothesised that the potent respiratory inhibitor NO would elicit similar effects. Indeed, the current work demonstrates that pre-exposure to NO-releasers elicits a > tenfold increase in IC50 for gentamicin against pathogenic E. coli (i.e. a huge decrease in lethality). It was therefore hypothesised that hyper-sensitivity to NO may have arisen in bacterial pathogens and that this trait could promote the acquisition of antibiotic-resistance mechanisms through enabling cells to persist in the presence of toxic levels of antibiotic. To test this hypothesis, genomics and microbiological approaches were used to screen a collection of E. coli clinical isolates for antibiotic susceptibility and NO tolerance, although the data did not support a correlation between increased carriage of antibiotic resistance genes and NO tolerance. However, the current work has important implications for how antibiotic susceptibility might be measured in future (i.e. ± NO) and underlines the evolutionary advantage for bacterial pathogens to maintain tolerance to toxic levels of NO.

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Utilization of Vector Autoregressive and Linear Transfer Models to Follow Up the Antibiotic Resistance Spiral in Gram-negative Bacteria From Cephalosporin Consumption to Colistin Resistance

Clinical Infectious Diseases ◽

10.1093/cid/ciy1086 ◽

2018 ◽

Vol 69 (8) ◽

pp. 1410-1421 ◽

Cited By ~ 2

Author(s):

Hajnalka Tóth ◽

Adina Fésűs ◽

Orsolya Kungler-Gorácz ◽

Bence Balázs ◽

László Majoros ◽

...

Keyword(s):

Antibiotic Resistance ◽

Carbapenem Resistance ◽

Gram Negative Bacteria ◽

Vicious Cycle ◽

Var Models ◽

Gram Negative ◽

Vector Autoregressive ◽

E Coli ◽

Cephalosporin Resistance ◽

Klebsiella Spp

Abstract Background Increasing antibiotic resistance may reciprocally affect consumption and lead to use of broader-spectrum alternatives; a vicious cycle that may gradually limit therapeutic options. Our aim in this study was to demonstrate this vicious cycle in gram-negative bacteria and show the utility of vector autoregressive (VAR) models for time-series analysis in explanatory and dependent roles simultaneously. Methods Monthly drug consumption data in defined daily doses per 100 bed-days and incidence densities of gram-negative bacteria (Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, and Acinetobacter baumannii) resistant to cephalosporins or to carbapenems were analyzed using VAR models. These were compared to linear transfer models used earlier. Results In case of all gram-negative bacteria, cephalosporin consumption led to increasing cephalosporin resistance, which provoked carbapenem use and consequent carbapenem resistance and finally increased colistin consumption, exemplifying the vicious cycle. Different species were involved in different ways. For example, cephalosporin-resistant Klebsiella spp. provoked carbapenem use less than E. coli, and the association between carbapenem resistance of P. aeruginosa and colistin use was weaker than that of A. baumannii. Colistin use led to decreased carbapenem use and decreased carbapenem resistance of P. aeruginosa but not of A. baumannii. Conclusions VAR models allow analysis of consumption and resistance series in a bidirectional manner. The reconstructed resistance spiral involved cephalosporin use augmenting cephalosporin resistance primarily in E. coli. This led to increased carbapenem use, provoking spread of carbapenem-resistant A. baumannii and consequent colistin use. Emergence of panresistance is fueled by such antibiotic-resistance spirals.

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609. Differing Genotypic Contexts Between E. coli and A. baumannii Modulate the Role of blaADC-7 in the Development of Antibiotic Collateral Sensitivity

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.678 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S284-S285

Author(s):

Erin McClure ◽

Julia Newman ◽

Nikhil Krishnan ◽

Joseph Rutter ◽

Andrea M Hujer ◽

...

Keyword(s):

Antibiotic Resistance ◽

Fold Increase ◽

Protein Product ◽

Coli Strain ◽

Fourth Generation ◽

Clinical Strain ◽

Health Crisis ◽

E Coli ◽

Collateral Sensitivity ◽

Resistance Evolution

Abstract Background Antibiotic resistance is a global health crisis. While persistent drug discovery of novel antibiotics has previously been relied upon to thwart resistance, evolution inevitably perseveres. While genes conferring antibiotic resistance have previously been characterized, it is unclear how varying genetic contexts can change the antibiotic resistance phenotype a given gene confers. Methods The DH10B strain of E. coli was transformed with a blaADC-7 plasmid. In 12 evolutionary replicates, the modified E. coli strain and a clinical strain of A. baumannii containing the same resistance gene were passaged daily for 10 days on cefepime gradient agar plates with gradually increasing concentrations of cefepime. MICs of cefepime and a diverse set of 15 other drugs were determined for the parental strains and after the final passage passage. MIC of cefepime after intermediary passages were determined for select replicates. Lastly the blaADC-7 gene after the final passage was sequenced. Results At the end of 10 passages, collateral sensitivity in A. baumannii was observed to tigecycline and fosfomycin in 5 and 6 replicates respectively, out of 12 total. 4 out of 12 E. coli replicates displayed collateral sensitivity to minocycline (Figure 1). In the third E. coli replicate, Sanger sequencing revealed a novel S286R mutation in blaADC-7 appearing in passage seven which preceded a several log fold increase in the MIC of cefepime (Figures 2 and 3). No additional mutations were found in the other evolutionary replicates. Conclusion Patterns of resistance varied among antibiotics of the same class, (e.g., tetracyclines, fourth-generation cephalosporins) in both E. coli and A. baumannii; however, A. baumannii expressed less widespread collateral resistance than E. coli. A previously undiscovered S286R mutation in blaADC-7 coincided with a pronounced increased in resistance to cefepime. Further studies are required to determine whether this mutation gives rise to a structural change in the protein product. Given that no other mutations were found, resistance to cefepime and subsequent collateral resistance to other antibiotics may have developed due to epigenetic changes or mutations outside the blaADC-7 genes. Indeed, future experiments with whole-genome sequencing may reveal such changes. Disclosures All authors: No reported disclosures.

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480. Molecular Characterization of Multidrug-Resistant Gram-Negative Pathogens in Three Tertiary Care Hospitals in Egypt

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.553 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S235-S235

Author(s):

Amani Kholy ◽

Samia A Girgis ◽

Arwa R Elmanakhly ◽

Mervat A F Shetta ◽

Dalia El- Kholy ◽

...

Keyword(s):

Molecular Characterization ◽

Resistance Genes ◽

Genetic Basis ◽

Tertiary Care ◽

Carbapenem Resistance ◽

Resistance Mechanisms ◽

Gram Negative ◽

E Coli ◽

Tertiary Care Hospitals

Abstract Background High rates of AMR among Gram-negative bacilli (GNB) have been reported from Egypt for almost 2 decades. Surveillance and identifying the genetic basis of AMR provide important information to optimize patient care. As there is no adequate data on the genetic basis of AMR in Egypt, we aimed to identify the molecular characterization of multi-drug-resistant (MDR) Gram-negative pathogens (GNP). Methods Three major tertiary-care hospitals in Egypt participated in the “Study for Monitoring Antimicrobial Resistance Trends” (SMART) from 2014 to 2016. Consecutive GNPs were identified and their susceptibility to antimicrobials were tested. Molecular identification of ESBL, AmpC, and carbapenemase resistance genes was conducted on MDR isolates. Results We enrolled 1,070 consecutive Gram-negative isolates; only one isolate per patient according to the standard protocol of (SMART). During 2014–2015, 578 GNP were studied. Enterobacteriaceae comprised 66% of the total isolates. K. pneumoniae and E. coli were the most common (29.8% and 29.4%). K. pneumoniae and E. coli were the predominant organisms in IAI (30.5% and 30.1%, respectively) and UTI (and 38.9% and 48.6%, respectively), while Acinetobacter baumannii was the most prevalent in RTI (40.2%). ESBL producers were phenotypically detected in 53% of K. pneumoniae, and 68% of E. coli. During 2016, 495 GNP were studied. ESBL continued to be high. For E. coli and K. pneunomiea, the most active antimicrobials were amikacin (≥93%), imipenem/meropenem (≥87%) and colistin (97%). Genetic study of ertapenem-resistant isolates and 50% of isolates with ESBL phenotype revealed ESβL production in more than 90% of isolates; blaCTXM-15 was detected in 71.4% and 68.5% in K. pneumoniae and E. coli, respectively, blaTEM-OSBL in 48.5% and47.5% of K. pneumoniae and E. coli, respectively. Carbapenem resistance genes were detected in 45.4% of isolates. In K. pneumoniae, OXA-48 dominated (40.6%), followed by NDM1 (23.7%) and OXA-232 (4.5%). Conclusion Our study detected alarming rates of resistance and identified many resistance mechanisms in clinical isolates from Egyptian hospitals. These high rates highlight the importance of continuous monitoring of the resistance trend and discovering the novel resistant mechanisms of resistance, and the underscores a national antimicrobial stewardship plan in Egypt. Disclosures All authors: No reported disclosures.

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AyigPmutant strain is a small colony variant ofE. coliand shows pleiotropic antibiotic resistance

Canadian Journal of Microbiology ◽

10.1139/cjm-2017-0347 ◽

2017 ◽

Vol 63 (12) ◽

pp. 961-969 ◽

Cited By ~ 6

Author(s):

Hui Xia ◽

Qiongwei Tang ◽

Jie Song ◽

Jiang Ye ◽

Haizhen Wu ◽

...

Keyword(s):

Antibiotic Resistance ◽

Genetic Basis ◽

Coenzyme Q ◽

Small Colony Variant ◽

E Coli ◽

Collateral Sensitivity ◽

Persistent Infections ◽

Antibiotic Resistance Profile ◽

Small Colony ◽

Insight Into

Small colony variants (SCVs) are a commonly observed subpopulation of bacteria that have a small colony size and distinctive biochemical characteristics. SCVs are more resistant than the wild type to some antibiotics and usually cause persistent infections in the clinic. SCV studies have been very active during the past 2 decades, especially Staphylococcus aureus SCVs. However, fewer studies on Escherichia coli SCVs exist, so we studied an E. coli SCV during an experiment involving the deletion of the yigP locus. PCR and DNA sequencing revealed that the SCV was attributable to a defect in the yigP function. Furthermore, we investigated the antibiotic resistance profile of the E. coli SCV and it showed increased erythromycin, kanamycin, and d-cycloserine resistance, but collateral sensitivity to ampicillin, polymyxin, chloramphenicol, tetracycline, rifampin, and nalidixic acid. We tried to determine the association between yigP and the pleiotropic antibiotic resistance of the SCV by analyzing biofilm formation, cellular morphology, and coenzyme Q (Q8) production. Our results indicated that impaired Q8biosynthesis was the primary factor that contributed to the increased resistance and collateral sensitivity of the SCV. This study offers a novel genetic basis for E. coli SCVs and an insight into the development of alternative antimicrobial strategies for clinical therapy.

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Carbapenem Resistance: Mechanisms and Drivers of Global Menace

Pathogenic Bacteria ◽

10.5772/intechopen.90100 ◽

2020 ◽

Cited By ~ 1

Author(s):

Bilal Aslam ◽

Maria Rasool ◽

Saima Muzammil ◽

Abu Baker Siddique ◽

Zeeshan Nawaz ◽

...

Keyword(s):

Global Health ◽

Protein Modification ◽

Carbapenem Resistance ◽

Resistance Mechanisms ◽

Health Concern ◽

E Coli ◽

Carbapenem Resistant ◽

Global Health Issue ◽

Class I Integrons ◽

Day By Day

The emergence of carbapenem-resistant bacterial pathogens is a significant and mounting health concern across the globe. At present, carbapenem resistance (CR) is considered as one of the most concerning resistance mechanisms and mainly found in gram-negative bacteria of the Enterobacteriaceae family. Although carbapenem resistance has been recognized in Enterobacteriaceae from last 20 years or so, recently it emerged as a global health issue as CR clonal dissemination of various Enterobacteriaceae members especially E. coli, and Klebsiella pneumoniae are reported from across the globe at an alarming rate. Phenotypically, carbapenems resistance is in due to the two key mechanisms, like structural mutation coupled with β-lactamase production and the ability of the pathogen to produce carbapenemases which ultimately hydrolyze the carbapenem. Additionally, penicillin-binding protein modification and efflux pumps are also responsible for the development of carbapenem resistance. Carbapenemases are classified into different classes which include Ambler classes A, B, and D. Several mobile genetic elements (MGEs) have their potential role in carbapenem resistance like Tn4401, Class I integrons, IncFIIK2, IncF1A, and IncI2. Taking together, resistance against carbapenems is continuously evolving and posing a significant health threat to the community. Variable mechanisms that are associated with carbapenem resistance, different MGEs, and supplementary mechanisms of antibiotic resistance in association with virulence factors are expanding day by day. Timely demonstration of this global health concern by using molecular tools, epidemiological investigations, and screening may permit the suitable measures to control this public health menace.

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Quinolone Resistance Reversion by Targeting the SOS Response

mBio ◽

10.1128/mbio.00971-17 ◽

2017 ◽

Vol 8 (5) ◽

Cited By ~ 26

Author(s):

E. Recacha ◽

J. Machuca ◽

P. Díaz de Alba ◽

M. Ramos-Güelfo ◽

F. Docobo-Pérez ◽

...

Keyword(s):

Antibiotic Resistance ◽

Antimicrobial Agents ◽

Sos Response ◽

Resistance Mechanisms ◽

Quinolone Resistance ◽

Resistant Bacteria ◽

Health Crisis ◽

E Coli ◽

Isogenic Strains

ABSTRACT Suppression of the SOS response has been postulated as a therapeutic strategy for potentiating antimicrobial agents. We aimed to evaluate the impact of its suppression on reversing resistance using a model of isogenic strains of Escherichia coli representing multiple levels of quinolone resistance. E. coli mutants exhibiting a spectrum of SOS activity were constructed from isogenic strains carrying quinolone resistance mechanisms with susceptible and resistant phenotypes. Changes in susceptibility were evaluated by static (MICs) and dynamic (killing curves or flow cytometry) methodologies. A peritoneal sepsis murine model was used to evaluate in vivo impact. Suppression of the SOS response was capable of resensitizing mutant strains with genes encoding three or four different resistance mechanisms (up to 15-fold reductions in MICs). Killing curve assays showed a clear disadvantage for survival (Δlog10 CFU per milliliter [CFU/ml] of 8 log units after 24 h), and the in vivo efficacy of ciprofloxacin was significantly enhanced (Δlog10 CFU/g of 1.76 log units) in resistant strains with a suppressed SOS response. This effect was evident even after short periods (60 min) of exposure. Suppression of the SOS response reverses antimicrobial resistance across a range of E. coli phenotypes from reduced susceptibility to highly resistant, playing a significant role in increasing the in vivo efficacy. IMPORTANCE The rapid rise of antibiotic resistance in bacterial pathogens is now considered a major global health crisis. New strategies are needed to block the development of resistance and to extend the life of antibiotics. The SOS response is a promising target for developing therapeutics to reduce the acquisition of antibiotic resistance and enhance the bactericidal activity of antimicrobial agents such as quinolones. Significant questions remain regarding its impact as a strategy for the reversion or resensitization of antibiotic-resistant bacteria. To address this question, we have generated E. coli mutants that exhibited a spectrum of SOS activity, ranging from a natural SOS response to a hypoinducible or constitutively suppressed response. We tested the effects of these mutations on quinolone resistance reversion under therapeutic concentrations in a set of isogenic strains carrying different combinations of chromosome- and plasmid-mediated quinolone resistance mechanisms with susceptible, low-level quinolone resistant, resistant, and highly resistant phenotypes. Our comprehensive analysis opens up a new strategy for reversing drug resistance by targeting the SOS response. IMPORTANCE The rapid rise of antibiotic resistance in bacterial pathogens is now considered a major global health crisis. New strategies are needed to block the development of resistance and to extend the life of antibiotics. The SOS response is a promising target for developing therapeutics to reduce the acquisition of antibiotic resistance and enhance the bactericidal activity of antimicrobial agents such as quinolones. Significant questions remain regarding its impact as a strategy for the reversion or resensitization of antibiotic-resistant bacteria. To address this question, we have generated E. coli mutants that exhibited a spectrum of SOS activity, ranging from a natural SOS response to a hypoinducible or constitutively suppressed response. We tested the effects of these mutations on quinolone resistance reversion under therapeutic concentrations in a set of isogenic strains carrying different combinations of chromosome- and plasmid-mediated quinolone resistance mechanisms with susceptible, low-level quinolone resistant, resistant, and highly resistant phenotypes. Our comprehensive analysis opens up a new strategy for reversing drug resistance by targeting the SOS response.

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Carriage of Carbapenem-Resistant Enterobacterales in Adult Patients Admitted to a University Hospital in Italy

Antibiotics ◽

10.3390/antibiotics10010061 ◽

2021 ◽

Vol 10 (1) ◽

pp. 61

Author(s):

Pamela Barbadoro ◽

Daniela Bencardino ◽

Elisa Carloni ◽

Enrica Omiccioli ◽

Elisa Ponzio ◽

...

Keyword(s):

Antibiotic Resistance ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Resistance Rate ◽

Coli Strain ◽

Adult Patients ◽

University Hospital ◽

E Coli ◽

Genetic Features ◽

Phenotypic Tests

The emerging spread of carbapenemase-producing Enterobacterales (CPE) strains, in particular, Klebsiella pneumoniae and Escherichia coli, has become a significant threat to hospitalized patients. Carbapenemase genes are frequently located on plasmids than can be exchanged among clonal strains, increasing the antibiotic resistance rate. The aim of this study was to determine the prevalence of CPE in patients upon their admission and to analyze selected associated factors. An investigation of the antibiotic resistance and genetic features of circulating CPE was carried out. Phenotypic tests and molecular typing were performed on 48 carbapenemase-producing strains of K. pneumoniae and E. coli collected from rectal swabs of adult patients. Carbapenem-resistance was confirmed by PCR detection of resistance genes. All strains were analyzed by PCR-based replicon typing (PBRT) and multilocus sequence typing (MLST) was performed on a representative isolate of each PBRT profile. More than 50% of the strains were found to be multidrug-resistant, and the blaKPC gene was detected in all the isolates with the exception of an E. coli strain. A multireplicon status was observed, and the most prevalent profile was FIIK, FIB KQ (33%). MLST analysis revealed the prevalence of sequence type 512 (ST512). This study highlights the importance of screening patients upon their admission to limit the spread of CRE in hospitals.

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The chemotherapeutic drug methotrexate selects for antibiotic resistance

10.1101/2020.11.12.378059 ◽

2020 ◽

Author(s):

Jónína S. Gudmundsdóttir ◽

Elizabeth G. A. Fredheim ◽

Catharina I. M. Koumans ◽

Joachim Hegstad ◽

Po-Cheng Tang ◽

...

Keyword(s):

Antibiotic Resistance ◽

Antibacterial Properties ◽

Treatment Strategies ◽

Bacterial Populations ◽

E Coli ◽

Resistance Evolution ◽

Selective Pressures ◽

Methotrexate Chemotherapy ◽

Selection Of

AbstractUnderstanding drivers of antibiotic resistance evolution is fundamental for designing optimal treatment strategies and interventions to reduce the spread of antibiotic resistance. Various cytotoxic drugs used in cancer chemotherapy have antibacterial properties, but how bacterial populations are affected by these selective pressures is unknown. Here we test the hypothesis that the widely used cytotoxic drug methotrexate affects the evolution and selection of antibiotic resistance through the same mechanisms as the antibiotic trimethoprim. We show that methotrexate can select for trimethoprim resistance determinants located on the chromosome or a plasmid in clinical strains of Escherichia coli. Additionally, methotrexate can co-select for virtually any antibiotic resistance determinant when present together with trimethoprim resistance on a multidrug-resistance clinical plasmid. These selective effects occur at concentrations 40- to >320-fold below the methotrexate minimal inhibitory concentration for E. coli, suggesting a selective role of methotrexate chemotherapy for antibiotic resistance in patients that strongly depend on effective antibiotic treatment.

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