scholarly journals Induction of Multidrug Resistance Mechanism in Escherichia coli Biofilms by Interplay between Tetracycline and Ampicillin Resistance Genes

2009 ◽  
Vol 53 (11) ◽  
pp. 4628-4639 ◽  
Author(s):  
Thithiwat May ◽  
Akinobu Ito ◽  
Satoshi Okabe
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Marker Genes ◽  
Ampicillin Resistance ◽  
High Level ◽  
Biofilm Development ◽  
Level Resistance

ABSTRACT Biofilms gain resistance to various antimicrobial agents, and the presence of antibiotic resistance genes is thought to contribute to a biofilm-mediated antibiotic resistance. Here we showed the interplay between the tetracycline resistance efflux pump TetA(C) and the ampicillin resistance gene (bla TEM-1) in biofilms of Escherichia coli harboring pBR322 in the presence of the mixture of ampicillin and tetracycline. E. coli in the biofilms could obtain the high-level resistance to ampicillin, tetracycline, penicillin, erythromycin, and chloramphenicol during biofilm development and maturation as a result of the interplay between the marker genes on the plasmids, the increase of plasmid copy number, and consequently the induction of the efflux systems on the bacterial chromosome, especially the EmrY/K and EvgA/S pumps. In addition, we characterized the overexpression of the TetA(C) pump that contributed to osmotic stress response and was involved in the induction of capsular colanic acid production, promoting formation of mature biofilms. However, this investigated phenomenon was highly dependent on the addition of the subinhibitory concentrations of antibiotic mixture, and the biofilm resistance behavior was limited to aminoglycoside antibiotics. Thus, marker genes on plasmids played an important role in both resistance of biofilm cells to antibiotics and in formation of mature biofilms, as they could trigger specific chromosomal resistance mechanisms to confer a high-level resistance during biofilm formation.

scholarly journals Improved Electrotransformation and Decreased Antibiotic Resistance of the Cystic Fibrosis Pathogen Burkholderia cenocepacia Strain J2315

2009 ◽  
Vol 76 (4) ◽  
pp. 1095-1102 ◽  
Author(s):  
Nelly Dubarry ◽  
Wenli Du ◽  
David Lane ◽  
Franck Pasta
Keyword(s):  
Cystic Fibrosis ◽  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Efflux Pump ◽  
Antibiotic Resistance Genes ◽  
Burkholderia Cenocepacia ◽  
The Poor ◽  
High Level

ABSTRACT The bacterium Burkholderia cenocepacia is pathogenic for sufferers from cystic fibrosis (CF) and certain immunocompromised conditions. The B. cenocepacia strain most frequently isolated from CF patients, and which serves as the reference for CF epidemiology, is J2315. The J2315 genome is split into three chromosomes and one plasmid. The strain was sequenced several years ago, and its annotation has been released recently. This information should allow genetic experimentation with J2315, but two major impediments appear: the poor potential of J2315 to act as a recipient in transformation and conjugation and the high level of resistance it mounts to nearly all antibiotics. Here, we describe modifications to the standard electroporation procedure that allow routine transformation of J2315 by DNA. In addition, we show that deletion of an efflux pump gene and addition of spermine to the medium enhance the sensitivity of J2315 to certain commonly used antibiotics and so allow a wider range of antibiotic resistance genes to be used for selection.

scholarly journals Antimicrobial Resistance Genes in Enterotoxigenic Escherichia coli O149:K91 Isolates Obtained over a 23-Year Period from Pigs

2003 ◽  
Vol 47 (10) ◽  
pp. 3214-3221 ◽  
Author(s):  
Christine Maynard ◽  
John M. Fairbrother ◽  
Sadjia Bekal ◽  
François Sanschagrin ◽  
Roger C. Levesque ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Antimicrobial Agents ◽  
Enterotoxigenic Escherichia Coli ◽  
Genotypic Resistance ◽  
Class 1 Integron ◽  
Phenotypic Resistance ◽  
Antimicrobial Resistance Genes

ABSTRACT A total of 112 Escherichia coli O149:K91 strains isolated from pigs with diarrhea in Quebec, Canada, between 1978 and 2000 were characterized for their genotypic antimicrobial resistance profiles. Tests for resistance to 10 antimicrobial agents were conducted. Resistance to tetracycline and sulfonamides was found to be the most frequent, but resistance to cefotaxime and ceftiofur was absent. An increase in the number of isolates resistant to at least three antimicrobials was observed over time. The distribution of 28 resistance genes covering six antimicrobial families (beta-lactams, aminoglycosides, phenicols, tetracycline, trimethoprim, and sulfonamides) was assessed by colony hybridization. Significant differences in the distributions of tetracycline [tet(A), tet(B), tet(C)], trimethoprim (dhfrI, dhfrV, dhfrXIII), and sulfonamide (sulI, sulII) resistance genes were observed during the study period (1978 to 2000). Sixty percent of the isolates possessed a class 1 integron, illustrating the importance of integrons in the epidemiology of antibiotic resistance in E. coli strains from pigs. Amplification of the integron's variable region resulted in four distinct fragments of 1, 1.3, 1.6, and 1.8 kb, with the 1.6- and 1.8-kb fragments appearing only during the last half of the study period. Examination of linkages among the different resistance genes showed a variety of positive and negative associations. Association analysis of isolates divided into two groups, those isolated between 1978 and 1989 and those isolated between 1990 and 2000, revealed the appearance of new positive resistance gene associations. Our genotypic resistance analyses of ETEC isolates from pigs indicate that many of the antibiotic resistance genes behind phenotypic resistance are not static but, rather, are in a state of flux driven by various selection forces such as the use of specific antimicrobials.

scholarly journals Susceptibility to antibiotics in escherichiae isolated in a multidisciplinary medical centre

2016 ◽  
Vol 65 (4) ◽  
pp. 83-89
Author(s):  
Nadezda S. Kozlova ◽  
Natalia E. Barantsevich ◽  
Elena P. Barantsevich
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Multidrug Resistance ◽  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
E Coli ◽  
Microdilution Method ◽  
Carbapenem Resistant ◽  
Resistant Strains ◽  
High Level

Relevance. Antimicrobial resistance in nosocomial strains currently presents a very important problem.  Aim of the study: Study of antibiotic resistance in Escherichia coli, isolated in a multidisciplinary centre.  Materials and Methods. Susceptibility of 151 E. coli strains to 15 antibiotics was studied by microdilution method. Results. The majority of the studied strains were resistant to antibiotics, including: ampicillin (57.0%), ciprofloxacin and moxifloxacin (42.4% each), III and IV generation cephalosporins (37.1% and 34.4%, respectively) and gentamycin (29.1%). The highest activity against E. coliwas shown for carbapenems (resistance to erthapenem – 2.6%, meropenem – 0.7%), in particular, for imipenem – no strains resistant to this drug were isolated. Resistance to amikacin and phosphomycin was low: 3.3% and 1.3% respectively. Wide diversity of antibiotic resistance spectra was revealed in studied strains, with a high level of multidrug resistance (48.0%). Conclusion. Study of susceptibility to antimicrobial agents in E. coli, isolated in a multidisciplinary centre, showed predominance of resistant strains with a high level of multidrug resistance. The appearance of carbapenem-resistant strains in a multidisciplinary centre presents a rising problem.

scholarly journals Analysis of antibiotic resistance phenotypes and genes of Escherichia coli from healthy swine in Guizhou, China

2021 ◽  
Vol 88 (1) ◽  
Author(s):  
Bo Yu ◽  
Yanan Zhang ◽  
Li Yang ◽  
Jinge Xu ◽  
Shijin Bu
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Detection Rate ◽  
Antimicrobial Agents ◽  
Antibiotic Resistance Genes ◽  
Multidrug Resistant ◽  
Multiple Drug ◽  
E Coli ◽  
Extended Spectrum

This study was carried out to investigate the resistance phenotypes and resistance genes of Escherichia coli from swine in Guizhou, China. A total of 47 E. coli strains isolated between 2013 and 2018 were tested using the Kirby–Bauer (K–B) method to verify their resistance to 19 common clinical antimicrobials. Five classes consisting of 29 resistance genes were detected using polymerase chain reaction. The status regarding extended-spectrum β-lactamase (ESBL) and the relationship between ESBL CTX-M-type β-lactamase genes and plasmid-mediated quinolone resistance (PMQR) genes were analysed. A total of 46 strains (97.9%) were found to be multidrug resistant. Amongst them, 27 strains (57.4%) were resistant to more than eight antimicrobials, and the maximum number of resistant antimicrobial agents was 16. Twenty antibiotic resistance genes were detected, including six β-lactamase genes blaTEM (74.5%), blaCTX-M-9G (29.8%), blaDHA (17.0%), blaCTX-M-1G (10.6%), blaSHV (8.5%), blaOXA (2.1%), five aminoglycoside-modifying enzyme genes aac(3′)-IV (93.6%), aadA1 (78.7%), aadA2 (76.6%), aac(3′)-II c (55.3%), aac(6′)-Ib (2.1%) and five amphenicol resistance genes floR (70.2%), cmlA (53.2%), cat2 (10.6%), cat1 (6.4%), cmlB (2.1%), three PMQR genes qnrS (55.3%), oqxA (53.2%), qepA (27.7%) and polypeptide resistance gene mcr-1 (40.4%). The detection rate of ESBL-positive strains was 80.9% (38/47) and ESBL TEM-type was the most abundant ESBLs. The percentage of the PMQR gene in blaCTX-M-positive strains was high, and the detection rate of blaCTX-M-9G was the highest in CTX-M type. It is clear that multiple drug resistant E. coli is common in healthy swine in this study. Extended-spectrum β-lactamase is very abundant in the E. coli strains isolated from swine and most of them are multiple compound genotypes.

scholarly journals Culturing Ancient Bacteria Carrying Resistance Genes from Permafrost and Comparative Genomics with Modern Isolates

2020 ◽  
Vol 8 (10) ◽  
pp. 1522
Author(s):  
Pamela Afouda ◽  
Grégory Dubourg ◽  
Anthony Levasseur ◽  
Pierre-Edouard Fournier ◽  
Jeremy Delerce ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Antimicrobial Agents ◽  
Bacterial Species ◽  
Acquired Resistance ◽  
Antibiotic Resistance Genes ◽  
Resistance Mechanisms ◽  
Genome Comparison ◽  
Antibiotics Use ◽  
High Level

Long considered to be a consequence of human antibiotics use by deduction, antibiotic resistance mechanisms appear to be in fact a much older phenomenon as antibiotic resistance genes have previously been detected from millions of year-old permafrost samples. As these specimens guarantee the viability of archaic bacteria, we herein propose to apply the culturomics approach to recover the bacterial content of a Siberian permafrost sample dated, using the in situ-produced cosmogenic nuclide chlorine36 (36Cl), at 2.7 million years to study the dynamics of bacterial evolution in an evolutionary perspective. As a result, we cultured and sequenced the genomes of 28 ancient bacterial species including one new species. To perform genome comparison between permafrost strains and modern isolates we selected 7 of these species (i.e., Achromobacter insolitus, Bacillus idriensis, Brevundimonas aurantiaca, Janibacter melonis, Kocuria rhizophila, Microbacterium hydrocarbonoxydans and Paracoccus yeei). We observed a high level of variability in genomic content with a percentage of shared genes in the core genomes ranging from 21.23% to 55.59%. In addition, the Single Nucleotide Polymorphism (SNP) comparison between permafrost and modern strains for the same species did not allow a dating of ancient strains based on genomic content. There were no significant differences in antibiotic resistance profiles between modern and ancient isolates of each species. Acquired resistance to antibiotics was phenotypically detected in all gram-negative bacterial species recovered from permafrost, with a significant number of genes coding for antibiotic resistance detected. Taken together, these findings confirm previously obtained data that antibiotic resistance predates humanity as most of antimicrobial agents are natural weapons used in inter-microbial conflicts within the biosphere.

scholarly journals Post-Covid-19 Era: What is Next?

2021 ◽  
Author(s):  
Shiela Chetri
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Carbapenem Resistance ◽  
Resistance Mechanisms ◽  
Multidrug Efflux Pump ◽  
High Risk Factors ◽  
Clinical Complications

Antimicrobial resistance (AMR) is a natural phenomenon in bacteria which becomes a threat for health-care settings around the world. A concerted global response is needed to tackle rising rates of antibiotic resistance, without it we risk returning to the pre antibiotic era. As bacteria evolve very fast according to the environment in which they inhabit via developing different defence mechanisms to combat with the noxious agents like different classes of antibiotics including carbapenems. This results into treatment failure and clinical complications. Global emergence of antibiotic resistance due to bacterial multidrug efflux pump systems are a major and common mechanism of intrinsic antimicrobial resistance employed by bacteria which are spreading rapidly due to over use or misuse of antimicrobial agents. This review mainly focusses on the transcriptional expression of efflux pump system AcrAB-TolC, local regulatory genes (AcrR and AcrS), mediating carbapenem resistance in clinical isolates of Escherichia coli under antibiotic stress, a genetic interplay study between intrinsic and acquired antibiotic resistance mechanisms along with a brief summary on high risk factors and prevalence of urinary tract infections by multidrug resistant Uropathogenic Escherichia coli.

scholarly journals Evaluation of Antibiotic Resistance Pattern of Escherichia coli Isolated From Broiler Chickens With Colibacillosis in Ardabil Province, Iran

2020 ◽  
Vol 5 (4) ◽  
pp. 125-130
Author(s):  
Aidin Azizpour ◽  
Ciamak Ghazaei
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Broiler Chickens ◽  
Antimicrobial Agents ◽  
Diffusion Method ◽  
Resistance Pattern ◽  
Economic Damage ◽  
Poultry Industry ◽  
Disk Diffusion Method ◽  
High Level

Introduction: Colibacillosis is one of the most important bacterial diseases of birds that is caused by Escherichia coli. This disease causes considerable economic damage to the poultry industry every year. Various antimicrobial agents are used to reduce the damage caused by this infection. But in recent decades, the increased use of antibiotics has led to the development of resistant genes and, consequently increasing antibiotic resistance of bacteria, leading to a decrease in the efficacy of antibiotics. The purpose of this study was to determine the susceptibility and drug resistance of 178 isolates of 40 chicken flocks in Ardabil province northwest of Iran. Methods: Five carcasses were randomly selected from each flocks with colibacillosis and sampled from liver and heart using sterile swabs. After culture and isolation, colonies were identified by biochemical and serological methods. Antibiotic resistance of all isolates to 19 antibiotics was determined using disk diffusion method based on CLSI guidelines. Results: Of 200 samples, 178 (89%) were isolated, and 22 (11%) did not grow. In this study the highest antibiotic resistance was observed against flumequine (98.31%), nalidixic acid (97.25%), tylosin (97.20%), oxytetracycline (97.20%), chlortetracycline (95.50%), difloxacin (89.32%), doxycycline (81.47%), enrofloxacin (77.53%), sulfamethoxazole + trimethoprim (71.91%), and the lowest antibiotic resistance was recorded for Linco-Spectin (36.52%), chloramphenicol (22.47%), gentamycin (7.30%), fuzbac (5.05%) and ceftriaxone (3.93%). All isolates were highly sensitive to ceftazidime. Conclusion: The results of this study showed a high level of resistance to antibiotics commonly used in poultry industry, which is probably due to improper use of antibiotics in poultries.

scholarly journals Molecular pathways to high-level azithromycin resistance in Neisseria gonorrhoeae

2021 ◽  
Author(s):  
J G E Laumen ◽  
S S Manoharan-Basil ◽  
E Verhoeven ◽  
S Abdellati ◽  
I De Baetselier ◽  
...  
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Ribosomal Proteins ◽  
Efflux Pump ◽  
23S Rrna ◽  
Rrna Gene ◽  
23S Rrna Gene ◽  
Evolution Of Resistance ◽  
High Level ◽  
Azithromycin Resistance ◽  
Level Resistance

Abstract Background The prevalence of azithromycin resistance in Neisseria gonorrhoeae is increasing in numerous populations worldwide. Objectives To characterize the genetic pathways leading to high-level azithromycin resistance. Methods A customized morbidostat was used to subject two N. gonorrhoeae reference strains (WHO-F and WHO-X) to dynamically sustained azithromycin pressure. We tracked stepwise evolution of resistance by whole genome sequencing. Results Within 26 days, all cultures evolved high-level azithromycin resistance. Typically, the first step towards resistance was found in transitory mutations in genes rplD, rplV and rpmH (encoding the ribosomal proteins L4, L22 and L34 respectively), followed by mutations in the MtrCDE-encoded efflux pump and the 23S rRNA gene. Low- to high-level resistance was associated with mutations in the ribosomal proteins and MtrCDE efflux pump. However, high-level resistance was consistently associated with mutations in the 23S ribosomal RNA, mainly the well-known A2059G and C2611T mutations, but also at position A2058G. Conclusions This study enabled us to track previously reported mutations and identify novel mutations in ribosomal proteins (L4, L22 and L34) that may play a role in the genesis of azithromycin resistance in N. gonorrhoeae.

scholarly journals Novel Soil-Derived Beta-Lactam, Chloramphenicol, Fosfomycin and Trimethoprim Resistance Genes Revealed by Functional Metagenomics

Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 378
Author(s):  
Inka Marie Willms ◽  
Maja Grote ◽  
Melissa Kocatürk ◽  
Lukas Singhoff ◽  
Alina Andrea Kraft ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Antibiotic Resistance Genes ◽  
Reference Database ◽  
Functional Metagenomics ◽  
Beta Lactam ◽  
Public Attention ◽  
Soil Ecosystems ◽  
High Level ◽  
Antibiotic Efflux

Antibiotic resistance genes (ARGs) in soil are considered to represent one of the largest environmental resistomes on our planet. As these genes can potentially be disseminated among microorganisms via horizontal gene transfer (HGT) and in some cases are acquired by clinical pathogens, knowledge about their diversity, mobility and encoded resistance spectra gained increasing public attention. This knowledge offers opportunities with respect to improved risk prediction and development of strategies to tackle antibiotic resistance, and might help to direct the design of novel antibiotics, before further resistances reach hospital settings or the animal sector. Here, metagenomic libraries, which comprise genes of cultivated microorganisms, but, importantly, also those carried by the uncultured microbial majority, were screened for novel ARGs from forest and grassland soils. We detected three new beta-lactam, a so far unknown chloramphenicol, a novel fosfomycin, as well as three previously undiscovered trimethoprim resistance genes. These ARGs were derived from phylogenetically diverse soil bacteria and predicted to encode antibiotic inactivation, antibiotic efflux, or alternative variants of target enzymes. Moreover, deduced gene products show a minimum identity of ~21% to reference database entries and confer high-level resistance. This highlights the vast potential of functional metagenomics for the discovery of novel ARGs from soil ecosystems.

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