scholarly journals Enhanced Survival of Rifampin- and Streptomycin-Resistant Escherichia coli Inside Macrophages

2016 ◽  
Vol 60 (7) ◽  
pp. 4324-4332 ◽  
Author(s):  
Paulo Durão ◽  
Daniela Gülereşi ◽  
João Proença ◽  
Isabel Gordo
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Multiple Drug Resistance ◽  
Host Cells ◽  
Resistant Bacteria ◽  
Multiple Drug ◽  
Bacterial Survival ◽  
Phagocytic Cells ◽  
Content Type ◽  
Multiple Paths

ABSTRACTThe evolution of multiple-antibiotic-resistant bacteria is an increasing global problem. Even though mutations causing resistance usually incur a fitness cost in the absence of antibiotics, the magnitude of such costs varies across environments and genomic backgrounds. We studied how the combination of mutations that confer resistance to rifampin (Rifr) and streptomycin (Strr) affects the fitness ofEscherichia coliwhen it interacts with cells from the immune system, i.e., macrophages (Mϕs). We found that 13 RifrStrrdoubly resistant genotypes, of the 16 tested, show a survival advantage inside Mϕs, indicating that double resistance can be highly beneficial in this environment. Our results suggest that there are multiple paths to acquire multiple-drug resistance in this context, i.e., if a clone carrying Rifrallele H526 or S531 acquires a second mutation conferring Strr, the resulting double mutant has a high probability of showing increased survival inside Mϕs. On the other hand, we found two cases of sign epistasis between mutations, leading to a significant decrease in bacterial survival. Remarkably, infection of Mϕs with one of these combinations, K88R+H526Y, resulted in an altered pattern of gene expression in the infected Mϕs. This indicates that the fitness effects of resistance may depend on the pattern of gene expression of infected host cells. Notwithstanding the benefits of resistance found inside Mϕs, the RifrStrrmutants have massive fitness costs when the bacteria divide outside Mϕs, indicating that the maintenance of double resistance may depend on the time spent within and outside phagocytic cells.

scholarly journals First Report ofblaIMP-14on a Plasmid Harboring Multiple Drug Resistance Genes in Escherichia coli Sequence Type 131

2016 ◽  
Vol 60 (8) ◽  
pp. 5068-5071 ◽  
Author(s):  
Nicole Stoesser ◽  
Anna E. Sheppard ◽  
Gisele Peirano ◽  
Robert P. Sebra ◽  
Tarah Lynch ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Multiple Drug Resistance ◽  
Carbapenem Resistance ◽  
Sequence Type ◽  
Multiple Drug ◽  
Class 1 Integron ◽  
Content Type ◽  
Carbapenem Resistant ◽  
Class 1

ABSTRACTTheblaIMP-14carbapenem resistance gene has largely previously been observed inPseudomonas aeruginosaandAcinetobacterspp. As part of global surveillance and sequencing of carbapenem-resistantEscherichia coli, we identified a sequence type 131 strain harboringblaIMP-14within a class 1 integron, itself nested within an ∼54-kb multidrug resistance region on an epidemic IncA/C2plasmid. The emergence ofblaIMP-14in this context in the ST131 lineage is of potential clinical concern.

scholarly journals Prevalence of tet(X4) in Escherichia coli From Duck Farms in Southeast China

2021 ◽  
Vol 12 ◽  
Author(s):  
Yang Yu ◽  
Chao-Yue Cui ◽  
Xu Kuang ◽  
Chong Chen ◽  
Min-Ge Wang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multiple Drug Resistance ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Multiple Drug ◽  
Southeast China ◽  
E Coli ◽  
Polymerase Chain ◽  
Human Infections ◽  
Primary Gene

ObjectivesCarbapenems, colistin, and tigecycline are critically important antibiotics in clinics. After the global appearance of blaNDM and mcr mediating the resistance to carbapenems and colistin, respectively, tigecycline becomes the last-resort drug against severe human infections caused by multidrug-resistant bacteria. Recently, a mobile tigecycline resistance gene tet(X4) has been identified in Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii that causes high resistance to tigecycline and other tetracyclines. In this study, the prevalence of tet(X4) in E. coli isolates from duck and goose farms in Southeast China was identified and characterized.MethodsFeces, soil, sewage, and dust samples were collected from duck and goose farms along with the southeast coast provinces of China. Antimicrobial susceptibility testing and polymerase chain reaction screening were performed to investigate the phenotype and genotype of tigecycline resistance. Conjugation, S1 pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing were used to determine the transferability, genetic location, and the genomic characteristics of tet(X4).ResultsIn total, 1,716 samples were collected, and 16 isolates (0.9%) recovered from Guangdong, Shandong, and Jiangsu were positive for tet(X4) gene with tigecycline minimum inhibitory concentrations ≥16 mg/L. Notably, among these tet(X4)-positive E. coil isolates, seven of them were from the environment samples (soil and sewage). PFGE and multilocus sequence typing demonstrated that ST3997 was the most prevalent sequence type (eight isolates, 50%) in Jiangsu province. By conjugation assays, 11 isolates were able to transfer tet(X4) plasmid to E. coli C600 recipient, and these plasmids belonged to IncHI1 and IncX1 detected by sequence analysis. tet(X4) was found adjacent to an insertion sequence ISCR2 downstream and a catD gene upstream for all isolates. In addition, multiple-drug resistance to tigecycline, chlortetracycline, ampicillin, florfenicol, ciprofloxacin, gentamicin, trimethoprim/sulfamethoxazole, and fosfomycin was profiled in most of the tet(X4)-positive isolates.ConclusionThe identification of tet(X4) harboring E. coli strains in duck farms and their surrounding environment enlarges our knowledge of the variety and prevalence of tigecycline resistance. The prevalence of tet(X4) raises concern for the use of tetracyclines in animal farming, and the tet(X4) gene should be listed as primary gene for resistance surveillance.

scholarly journals Occurrence of Antimicrobial-Resistant Escherichia coli and Salmonella enterica in the Beef Cattle Production and Processing Continuum

2014 ◽  
Vol 81 (2) ◽  
pp. 713-725 ◽  
Author(s):  
John W. Schmidt ◽  
Getahun E. Agga ◽  
Joseph M. Bosilevac ◽  
Dayna M. Brichta-Harhay ◽  
Steven D. Shackelford ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Generation Cephalosporin ◽  
Resistant Bacteria ◽  
Processing Plant ◽  
Cattle Production ◽  
Content Type ◽  
E Coli ◽  
Beef Processing ◽  
Tract Infections

ABSTRACTSpecific concerns have been raised that third-generation cephalosporin-resistant (3GCr)Escherichia coli, trimethoprim-sulfamethoxazole-resistant (COTr)E. coli, 3GCrSalmonella enterica, and nalidixic acid-resistant (NALr)S. entericamay be present in cattle production environments, persist through beef processing, and contaminate final products. The prevalences and concentrations of these organisms were determined in feces and hides (at feedlot and processing plant), pre-evisceration carcasses, and final carcasses from three lots of fed cattle (n= 184). The prevalences and concentrations were further determined for strip loins from 103 of the carcasses. 3GCrSalmonellawas detected on 7.6% of hides during processing and was not detected on the final carcasses or strip loins. NALrS. entericawas detected on only one hide. 3GCrE. coliand COTrE. coliwere detected on 100.0% of hides during processing. Concentrations of 3GCrE. coliand COTrE. colion hides were correlated with pre-evisceration carcass contamination. 3GCrE. coliand COTrE. coliwere each detected on only 0.5% of final carcasses and were not detected on strip loins. Five hundred and 42 isolates were screened for extraintestinal pathogenicE. coli(ExPEC) virulence-associated markers. Only two COTrE. coliisolates from hides were ExPEC, indicating that fed cattle products are not a significant source of ExPEC causing human urinary tract infections. The very low prevalences of these organisms on final carcasses and their absence on strip loins demonstrate that current sanitary dressing procedures and processing interventions are effective against antimicrobial-resistant bacteria.

scholarly journals Pathovar Transcriptomes

mSystems ◽  
2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Amy Platenkamp ◽  
Jay L. Mellies
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Regulatory Networks ◽  
Virulence Gene ◽  
Model System ◽  
Genomic Sequences ◽  
Bacterial Strains ◽  
Content Type ◽  
Virulence Gene Expression ◽  
Link Type

ABSTRACT Archetypal pathogenic bacterial strains are often used to elucidate regulatory networks of an entire pathovar, which encompasses multiple lineages and phylogroups. With enteropathogenic Escherichia coli (EPEC) as a model system, Hazen and colleagues (mSystems 6:e00024-17, 2017, https://doi.org/10.1128/mSystems.00024-17 ) used 9 isolates representing 8 lineages and 3 phylogroups to find that isolates with similar genomic sequences exhibit similarities in global transcriptomes under conditions of growth in medium that induces virulence gene expression, and they found variation among individual isolates. Archetypal pathogenic bacterial strains are often used to elucidate regulatory networks of an entire pathovar, which encompasses multiple lineages and phylogroups. With enteropathogenic Escherichia coli (EPEC) as a model system, Hazen and colleagues (mSystems 6:e00024-17, 2017, https://doi.org/10.1128/mSystems.00024-17 ) used 9 isolates representing 8 lineages and 3 phylogroups to find that isolates with similar genomic sequences exhibit similarities in global transcriptomes under conditions of growth in medium that induces virulence gene expression. They also found variation among individual isolates. Their work illustrates the importance of moving beyond observing regulatory phenomena of a limited number of regulons in a few archetypal strains, with the possibility of correlating clinical symptoms to key transcriptional pathways across lineages and phylogroups.

Antibiotic susceptibility testing of bacteria in drinking water sources in Akungba‐Akoko, Ondo State, Nigeria

2011 ◽  
Vol 1 (4) ◽  
pp. 233-237
Author(s):  
A. O. Ajayi ◽  
N. F. Agangan
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Multiple Drug Resistance ◽  
Antibiotic Sensitivity ◽  
Water Sources ◽  
Resistant Bacteria ◽  
Multiple Drug ◽  
Antibiotic Resistant ◽  
Antibiotic Sensitivity Test ◽  
The University

In present investigation, the bacteriological analysis and antibiotic sensitivitypattern of drinking water samples collected from different sources ofAkungba Ã¢â‚¬ÂAkoko, Nigeria was done. The antibiotics mainly considered in ourstudy for determining the sensitivity were amongst the commonly used inthis area for treatment of infectious diseases. As a result, the bacteriologicalindex, especially coliform count was observed notably high with 72 x10 1 cfu/ml for stream sample and 26.4 x 10 1 cfu/ml for borehole sample. The majorbacterial isolates identified in the water samples were Staphylococcus sp,E.coli  Ã¢â‚¬Ânegative bacteria wereobserved showing 75% and 65% resistant to Septrin and Amoxicillin respectively.Also, multiple drug resistance was observed for many antibiotics.Therefore, the presence of high amount antibiotic resistant bacteria of clinicalimportance is reported in these water sources which are usually consumedby students and members of the University community. Hence, thisstudy necessitates the need for water treatment so that epidemics of waterbornebacterial disease can be averted in this region., Klebsiella sp, Pseudomonas sp., Enterococcus sp., Bacillus cereus andothers. With regards to the antibiotic sensitivity test, all isolates showed100% resistance to Ampicillin and Cloxacillin and 85.7% resistance to Zinnacef[a cephalosporin product]. However, the gram 

Characterization of novel ybjG and dacC variants in Escherichia coli

2013 ◽  
Vol 62 (11) ◽  
pp. 1728-1734 ◽  
Author(s):  
Dongguo Wang ◽  
Enping Hu ◽  
Jiayu Chen ◽  
Xiulin Tao ◽  
Katelyn Gutierrez ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multiple Drug Resistance ◽  
Multiple Drug ◽  
The Novel ◽  
Conventional Pcr ◽  
E Coli ◽  
Novel Variants ◽  
Restriction Sites ◽  
Genetic Structures

A total of 69 strains of Escherichia coli from patients in the Taizhou Municipal Hospital, China, were isolated, and 11 strains were identified that were resistant to bacitracin, chloramphenicol, tetracycline and erythromycin. These strains were PCR positive for at least two out of three genes, ybjG, dacC and mdfA, by gene mapping with conventional PCR detection. Conjugation experiments demonstrated that these genes existed in plasmids that conferred resistance. Novel ybjG and dacC variants were isolated from E. coli strains EC2163 and EC2347, which were obtained from the sputum of intensive care unit patients. Genetic mapping showed that the genes were located on 8200 kb plasmid regions flanked by EcoRI restriction sites. Three distinct genetic structures were identified among the 11 PCR-positive strains of E. coli, and two contained the novel ybjG and dacC variants. The putative amino acid differences in the ybjG and dacC gene variants were characterized. These results provide evidence for novel variants of ybjG and dacC, and suggest that multiple drug resistance in hospital strains of E. coli depends on the synergistic function of ybjG, dacC and mdfA within three distinct genetic structures in conjugative plasmids.

scholarly journals The Repeat-In-Toxin Family Member TosA Mediates Adherence of Uropathogenic Escherichia coli and Survival during Bacteremia

2011 ◽  
Vol 80 (2) ◽  
pp. 493-505 ◽  
Author(s):  
Patrick D. Vigil ◽  
Travis J. Wiles ◽  
Michael D. Engstrom ◽  
Lev Prasov ◽  
Matthew A. Mulvey ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Virulence Factors ◽  
Upper Urinary Tract ◽  
Host Cells ◽  
Content Type ◽  
E Coli ◽  
Wide Range ◽  
Novel Target ◽  
Tract Infections

ABSTRACTUropathogenicEscherichia coli(UPEC) is responsible for the majority of uncomplicated urinary tract infections (UTI) and represents the most common bacterial infection in adults. UPEC utilizes a wide range of virulence factors to colonize the host, including the novel repeat-in-toxin (RTX) protein TosA, which is specifically expressed in the host urinary tract and contributes significantly to the virulence and survival of UPEC.tosA, found in strains within the B2 phylogenetic subgroup ofE. coli, serves as a marker for strains that also contain a large number of well-characterized UPEC virulence factors. The presence oftosAin anE. coliisolate predicts successful colonization of the murine model of ascending UTI, regardless of the source of the isolate. Here, a detailed analysis of the function oftosArevealed that this gene is transcriptionally linked to genes encoding a conserved type 1 secretion system similar to other RTX family members. TosA localized to the cell surface and was found to mediate (i) adherence to host cells derived from the upper urinary tract and (ii) survival in disseminated infections and (iii) to enhance lethality during sepsis (as assessed in two different animal models of infection). An experimental vaccine, using purified TosA, protected vaccinated animals against urosepsis. From this work, it was concluded that TosA belongs to a novel group of RTX proteins that mediate adherence and host damage during UTI and urosepsis and could be a novel target for the development of therapeutics to treat ascending UTIs.

scholarly journals Mycobacterium tuberculosis Alters the Metalloprotease Activity of the COP9 Signalosome

mBio ◽  
2014 ◽  
Vol 5 (4) ◽  
Author(s):  
Lia Danelishvili ◽  
Lmar Babrak ◽  
Sasha J. Rose ◽  
Jamie Everman ◽  
Luiz E. Bermudez
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Cop9 Signalosome ◽  
Virulence Determinants ◽  
Bacterial Survival ◽  
Phagocytic Cells ◽  
Content Type ◽  
Metalloprotease Activity ◽  
Macrophage Protein

ABSTRACT Inhibition of apoptotic death of macrophages by Mycobacterium tuberculosis represents an important mechanism of virulence that results in pathogen survival both in vitro and in vivo. To identify M. tuberculosis virulence determinants involved in the modulation of apoptosis, we previously screened a transposon bank of mutants in human macrophages, and an M. tuberculosis clone with a nonfunctional Rv3354 gene was identified as incompetent to suppress apoptosis. Here, we show that the Rv3354 gene encodes a protein kinase that is secreted within mononuclear phagocytic cells and is required for M. tuberculosis virulence. The Rv3354 effector targets the metalloprotease (JAMM) domain within subunit 5 of the COP9 signalosome (CSN5), resulting in suppression of apoptosis and in the destabilization of CSN function and regulatory cullin-RING ubiquitin E3 enzymatic activity. Our observation suggests that alteration of the metalloprotease activity of CSN by Rv3354 possibly prevents the ubiquitin-dependent proteolysis of M. tuberculosis-secreted proteins. IMPORTANCE Macrophage protein degradation is regulated by a protein complex called a signalosome. One of the signalosomes associated with activation of ubiquitin and protein labeling for degradation was found to interact with a secreted protein from M. tuberculosis, which binds to the complex and inactivates it. The interference with the ability to inactivate bacterial proteins secreted in the phagocyte cytosol may have crucial importance for bacterial survival within the phagocyte.

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