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Hassannia M, Naderifar M, Salamy S, Akbarizadeh MR, Mohebi S, Moghadam MT. Engineered phage enzymes against drug-resistant pathogens: a review on advances and applications. Bioprocess Biosyst Eng 2024; 47:301-312. [PMID: 37962644 DOI: 10.1007/s00449-023-02938-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 10/16/2023] [Indexed: 11/15/2023]
Abstract
In recent decades, the expansion of multi and extensively drug-resistant (MDR and XDR) bacteria has reached an alarming rate, causing serious health concerns. Infections caused by drug-resistant bacteria have been associated with morbidity and mortality, making tackling bacterial resistance an urgent and unmet challenge that needs to be addressed properly. Endolysins are phage-encoded enzymes that can specifically degrade the bacterial cell wall and lead to bacterial death. There is remarkable evidence that corroborates the unique ability of endolysins to rapidly digest the peptidoglycan particular bonds externally without the assistance of phage. Thus, their modulation in therapeutic approaches has opened new options for therapeutic applications in the fight against bacterial infections in the human and veterinary sectors, as well as within the agricultural and biotechnology areas. The use of genetically engineered phage enzymes (EPE) promises to generate endolysin variants with unique properties for prophylactic and therapeutic applications. These approaches have gained momentum to accelerate basic as well as translational phage research and the potential development of therapeutics in the near future. This review will focus on the novel knowledge into EPE and demonstrate that EPE has far better performance than natural endolysins and phages in dealing with antibiotic-resistant infections. Therefore, it provides essential information for clinical trials involving EPE.
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Affiliation(s)
- Mohadeseh Hassannia
- Department of Genetic, Faculty of Science, Islamic Azad University, Tehran, Iran
| | - Mahin Naderifar
- School of Medicine, Zabol University of Medical Sciences, Zabol, Iran
| | - Shakiba Salamy
- Department of Microbiology, Faculty of Pharmacy, Islamic Azad University, Tehran, Iran
| | | | - Samane Mohebi
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Boroujeni MB, Mohebi S, Malekian A, Shahraeini SS, Gharagheizi Z, Shahkolahi S, Sadeghi RV, Naderifar M, Akbarizadeh MR, Soltaninejad S, Moghadam ZT, Moghadam MT, Mirzadeh F. The therapeutic effect of engineered phage, derived protein and enzymes against superbug bacteria. Biotechnol Bioeng 2024; 121:82-99. [PMID: 37881139 DOI: 10.1002/bit.28581] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 09/18/2023] [Accepted: 10/15/2023] [Indexed: 10/27/2023]
Abstract
Defending against antibiotic-resistant infections is similar to fighting a war with limited ammunition. As the new century unfolded, antibiotic resistance became a significant concern. In spite of the fact that phage treatment has been used as an effective means of fighting infections for more than a century, researchers have had to overcome many challenges of superbug bacteria by manipulating phages and producing engineered enzymes. New enzymes and phages with enhanced properties have a significant impact on the ability to fight antibiotic-resistant infections, which is considered a window of hope for the future. This review, therefore, illustrates not only the challenges caused by antibiotic resistance and superbug bacteria but also the engineered enzymes and phages that are being developed to solve these issues. Our study found that engineered phages, phage proteins, and enzymes can be effective in treating superbug bacteria and destroying the biofilm caused by them. Combining these engineered compounds with other antimicrobial substances can increase their effectiveness against antibiotic-resistant bacteria. Therefore, engineered phages, proteins, and enzymes can be used as a substitute for antibiotics or in combination with antibiotics to treat patients with superbug infections in the future.
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Affiliation(s)
| | - Samane Mohebi
- Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Azam Malekian
- Department of Parasitology, Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Sadegh Shahraeini
- Department of Medical Biotechnology, Drug Design and Bioinformatics Unit, Biotechnology Research Centre, Pasteur Institute of Iran, Tehran, Iran
| | - Zahra Gharagheizi
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Shaghayegh Shahkolahi
- Department of Microbiology, North Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Rezvaneh Vahedian Sadeghi
- Department of Microbiology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mahin Naderifar
- School of Nursing & Midwifery, Zabol University of Medical Sciences, Zabol, Iran
| | | | | | - Zahra Taati Moghadam
- School of Nursing and Midwifery, Guilan University of Medical Sciences, Rasht, Iran
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Naidoo N, Zishiri OT. Comparative genomics analysis and characterization of Shiga toxin-producing Escherichia coli O157:H7 strains reveal virulence genes, resistance genes, prophages and plasmids. BMC Genomics 2023; 24:791. [PMID: 38124028 PMCID: PMC10731853 DOI: 10.1186/s12864-023-09902-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023] Open
Abstract
Escherichia coli O157:H7 is a foodborne pathogen that has been linked to global disease outbreaks. These diseases include hemorrhagic colitis and hemolytic uremic syndrome. It is vital to know the features that make this strain pathogenic to understand the development of disease outbreaks. In the current study, a comparative genomic analysis was carried out to determine the presence of structural and functional features of O157:H7 strains obtained from 115 National Center for Biotechnology Information database. These strains of interest were analysed in the following programs: BLAST Ring Image Generator, PlasmidFinder, ResFinder, VirulenceFinder, IslandViewer 4 and PHASTER. Five strains (ECP19-198, ECP19-798, F7508, F8952, H2495) demonstrated a great homology with Sakai because of a few regions missing. Five resistant genes were identified, however, Macrolide-associated resistance gene mdf(A) was commonly found in all genomes. Majority of the strains (97%) were positive for 15 of the virulent genes (espA, espB, espF, espJ, gad, chuA, eae, iss, nleA, nleB, nleC, ompT, tccP, terC and tir). The plasmid analysis demonstrated that the IncF group was the most prevalent in the strains analysed. The prophage and genomic island analysis showed a distribution of bacteriophages and genomic islands respectively. The results indicated that structural and functional features of the many O157:H7 strains differ and may be a result of obtaining mobile genetic elements via horizontal gene transfer. Understanding the evolution of O157:H7 strains pathogenicity in terms of their structural and functional features will enable the development of detection and control of transmission strategies.
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Affiliation(s)
- Natalie Naidoo
- School of Life Sciences, College of Agriculture, Engineering and Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa.
| | - Oliver T Zishiri
- School of Life Sciences, College of Agriculture, Engineering and Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa
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Kuznetsova MV, Pospelova JS, Maslennikova IL, Starčič Erjavec M. Dual-Species Biofilms: Biomass, Viable Cell Ratio/Cross-Species Interactions, Conjugative Transfer. Int J Mol Sci 2023; 24:14497. [PMID: 37833945 PMCID: PMC10572544 DOI: 10.3390/ijms241914497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 10/15/2023] Open
Abstract
Biofilms as a form of adaptation are beneficial for bacterial survival and may be hot spots for horizontal gene transfer, including conjugation. The aim of this research was to characterize the biofilm biomass, viable cell ratios and conjugative transfer of the pOX38 plasmid, an F-plasmid derivative, from the Escherichia coli N4i pOX38 strain (donor) into a uropathogenic E. coli DL82 strain (recipient) within dual-species biofilms with one of the following opportunistic pathogenic bacteria: Klebsiella pneumoniae, Enterococcus faecalis or Pseudomonas aeruginosa. Dual-species biofilms of E. coli with K. pneumoniae or P. aeruginosa but not E. faecalis were more massive and possessed more exopolysaccharide matrix compared to single-species biofilms of donor and recipient cells. Correlation between biofilm biomass and exopolysaccharide matrix was rs = 0.888 in dual-species biofilms. In dual-species biofilm with E. faecalis the proportion of E. coli was the highest, while in the biofilm with P. aeruginosa and K. pneumoniae, the E. coli was less abundant. The conjugative frequencies of plasmid transfer in dual-species biofilms of E. coli with E. faecalis and P. aeruginosa were reduced. A decrease in conjugative frequency was also observed when cell-free supernatants (CFSs) of E. faecalis and P. aeruginosa were added to the E. coli conjugation mixture. Further, the activity of the autoinducer AI-2 in the CFSs of the E. coli conjugation mixture was reduced when bacteria or CFSs of E. faecalis and P. aeruginosa were added to the E. coli conjugation mixture. Hence, the intercellular and interspecies interactions in dual-species biofilms depend on the partners involved.
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Affiliation(s)
- Marina V Kuznetsova
- Institute of Ecology and Genetics of Microorganisms Ural Branch Russian Academy of Sciences, 614081 Perm, Russia
| | | | - Irina L Maslennikova
- Institute of Ecology and Genetics of Microorganisms Ural Branch Russian Academy of Sciences, 614081 Perm, Russia
| | - Marjanca Starčič Erjavec
- Department of Microbiology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
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Whelan S, Lucey B, Finn K. Uropathogenic Escherichia coli (UPEC)-Associated Urinary Tract Infections: The Molecular Basis for Challenges to Effective Treatment. Microorganisms 2023; 11:2169. [PMID: 37764013 PMCID: PMC10537683 DOI: 10.3390/microorganisms11092169] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/23/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023] Open
Abstract
Urinary tract infections (UTIs) are among the most common bacterial infections, especially among women and older adults, leading to a significant global healthcare cost burden. Uropathogenic Escherichia coli (UPEC) are the most common cause and accounts for the majority of community-acquired UTIs. Infection by UPEC can cause discomfort, polyuria, and fever. More serious clinical consequences can result in urosepsis, kidney damage, and death. UPEC is a highly adaptive pathogen which presents significant treatment challenges rooted in a complex interplay of molecular factors that allow UPEC to evade host defences, persist within the urinary tract, and resist antibiotic therapy. This review discusses these factors, which include the key genes responsible for adhesion, toxin production, and iron acquisition. Additionally, it addresses antibiotic resistance mechanisms, including chromosomal gene mutations, antibiotic deactivating enzymes, drug efflux, and the role of mobile genetic elements in their dissemination. Furthermore, we provide a forward-looking analysis of emerging alternative therapies, such as phage therapy, nano-formulations, and interventions based on nanomaterials, as well as vaccines and strategies for immunomodulation. This review underscores the continued need for research into the molecular basis of pathogenesis and antimicrobial resistance in the treatment of UPEC, as well as the need for clinically guided treatment of UTIs, particularly in light of the rapid spread of multidrug resistance.
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Affiliation(s)
- Shane Whelan
- Department of Biological Sciences, Munster Technological University, Bishopstown, T12 P928 Cork, Ireland;
| | - Brigid Lucey
- Department of Biological Sciences, Munster Technological University, Bishopstown, T12 P928 Cork, Ireland;
| | - Karen Finn
- Department of Analytical, Biopharmaceutical and Medical Sciences, Atlantic Technological University Galway City, Dublin Road, H91 T8NW Galway, Ireland
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Molecular Factors and Mechanisms Driving Multidrug Resistance in Uropathogenic Escherichia coli-An Update. Genes (Basel) 2022; 13:genes13081397. [PMID: 36011308 PMCID: PMC9407594 DOI: 10.3390/genes13081397] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/28/2022] [Accepted: 08/03/2022] [Indexed: 02/06/2023] Open
Abstract
The rapid emergence of multidrug-resistant (MDR) bacteria indisputably constitutes a major global health problem. Pathogenic Escherichia coli are listed among the most critical group of bacteria that require fast development of new antibiotics and innovative treatment strategies. Among harmful extraintestinal Enterobacteriaceae strains, uropathogenic E. coli (UPEC) pose a significant health threat. UPEC are considered the major causative factor of urinary tract infection (UTI), the second-most commonly diagnosed infectious disease in humans worldwide. UTI treatment places a substantial financial burden on healthcare systems. Most importantly, the misuse of antibiotics during treatment has caused selection of strains with the ability to acquire MDR via miscellaneous mechanisms resulting in gaining resistance against many commonly prescribed antibiotics like ampicillin, gentamicin, cotrimoxazole and quinolones. Mobile genetic elements (MGEs) such as transposons, integrons and conjugative plasmids are the major drivers in spreading resistance genes in UPEC. The co-occurrence of various bacterial evasion strategies involving MGEs and the SOS stress response system requires further research and can potentially lead to the discovery of new, much-awaited therapeutic targets. Here, we analyzed and summarized recent discoveries regarding the role, mechanisms, and perspectives of MDR in the pathogenicity of UPEC.
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A Biomimetic Porcine Urothelial Model for Assessing Escherichia coli Pathogenicity. Microorganisms 2022; 10:microorganisms10040783. [PMID: 35456833 PMCID: PMC9029248 DOI: 10.3390/microorganisms10040783] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/20/2022] [Accepted: 04/01/2022] [Indexed: 02/01/2023] Open
Abstract
Urinary tract infections can be severe, sometimes fatal, diseases whose etiological pathogens are predominantly uropathogenic strains of E. coli (UPEC). To investigate the UPEC pathogenesis, several models have already been established with minor or major disadvantages. The aim was to develop a simple, fast, and inexpensive biomimetic in vitro model based on normal porcine urothelial (NPU) cells that are genetically and physiologically similar to human bladder urothelium and to perform basic studies of E. coli pathogenicity. Initially, the model was tested using a set of control E. coli strains and, subsequently, with human E. coli strains isolated either from patients with urinary infections or from the feces of healthy individuals. A drop in viability of NPU cells was used as a measure of the pathogenicity of the individual strain tested. To visualize the subcellular events, transmission and scanning electron microscopy was performed. The strains were tested for the presence of different virulence-associated genes, phylogroup, type of core lipid, O-serotype, and type of lipopolysaccharide and a statistical analysis of possible correlations between strains’ characteristics and the effect on the model was performed. Results showed that our model has the discriminatory power to distinguish pathogenic from non-pathogenic E. coli strains, and to identify new, potentially pathogenic strains.
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Rezatofighi SE, Mirzarazi M, Salehi M. Virulence genes and phylogenetic groups of uropathogenic Escherichia coli isolates from patients with urinary tract infection and uninfected control subjects: a case-control study. BMC Infect Dis 2021; 21:361. [PMID: 33865334 PMCID: PMC8052790 DOI: 10.1186/s12879-021-06036-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 04/05/2021] [Indexed: 12/02/2022] Open
Abstract
Background Urinary Tract Infection (UTI) is one of the most common bacterial infectious diseases which causes considerable morbidity and costly health problems. Uropathogenic Escherichia coli (UPEC), the most common pathogen causing UTI, is a highly heterogeneous group of extraintestinal pathogenic E. coli (ExPEC) which may carry a variety of virulence factors and belonging to different phylogenetic backgrounds. The current study aimed to investigate the frequency and association between various virulence factors (VFs) and phylogenetic groups of UPEC and commensal isolates. Methods UPEC and commensal E. coli strains isolated from UTI and feces of healthy humans were compared for the presence of VFs and phylogenetic groups. Association between virulence genes was investigated and cluster analysis was employed. Results According to the results, among a 30 virulence markers tested, the pathogenicity-associated island (PAI), papAH, papEF, fimH, fyuA, and traT genes prevalence were statistically significant in UPEC isolates. A strong association was found between the B2 and D phylogenetic groups and clinical isolates of UPEC; while, commensal isolates were mostly associated with phylogenetic group A. The aggregated VFs scores were more than twice higher in the UPEC isolates in comparison with the commensal isolates. Interestingly, the B2 group in both UPEC and commensal isolates had the highest VF scores. A strong positive association was found between several virulence genes. The clustering results demonstrated that UPEC or commensal E. coli isolates were highly heterogeneous due to different composition of their virulence gene pool and pathogenicity islands. Conclusion Genetic structure and VFs of UPEC strains vary from region to region; therefore, to control the UTI, the epidemiological aspects and characterization of the UPEC isolates need to be investigated in different regions. Since UPEC isolates are generally originate from the commensal strains, it may be feasible to reduce the UTI burden by interfering the intestinal colonization, particularly in the highly pathogenic clonal lineages such as B2.
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Affiliation(s)
- Seyedeh Elham Rezatofighi
- Department of biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, 6135743135, Iran.
| | - Mahsa Mirzarazi
- Department of biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, 6135743135, Iran
| | - Mansour Salehi
- Department of Genetics and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran
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Characterization of antibiotic resistance integrons harbored by Romanian Escherichia coli uropathogenic strains. REV ROMANA MED LAB 2020. [DOI: 10.2478/rrlm-2020-0023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Because little is known about the integrons which constitute an important means of spreading resistance in bacteria circulating in Romania, this study aimed to detect antibiotic resistance gene cassettes embedded in integrons in a convenient collection of 60 ciprofloxacin-resistant Escherichia coli isolates of various phylogroups, associated with community-acquired urinary tract infections. Characterization of the integrons was accomplished by PCR, restriction fragment length polymorphism typing, and DNA sequencing of each identified type. More than half of the tested E. coli strains were positive for integrons of class 1 (31 strains) or 2 (1 strain). These strains derived more frequently from phylogenetic groups A (15 of 21 strains), B1 (10 of 14 strains), and F (3 of 4 strains), respectively. While 20 strains carried class 1 integrons which could be assigned to nine types, eleven strains carried integrons that lacked the 3’-end conserved segment. The attempts made to characterize the gene cassettes located within the variable region of the various integrons identified in this study revealed the presence of genes encoding resistance to trimethoprim, aminoglycosides, beta-lactams or chloramphenicol. The evidence of transferable resistance determinants already established in the autochthonous E. coli strains highlights the need for improved control of resistance-carrying bacteria.
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Lacerda Mariano L, Ingersoll MA. The immune response to infection in the bladder. Nat Rev Urol 2020; 17:439-458. [PMID: 32661333 DOI: 10.1038/s41585-020-0350-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2020] [Indexed: 12/22/2022]
Abstract
The bladder is continuously protected by passive defences such as a mucus layer, antimicrobial peptides and secretory immunoglobulins; however, these defences are occasionally overcome by invading bacteria that can induce a strong host inflammatory response in the bladder. The urothelium and resident immune cells produce additional defence molecules, cytokines and chemokines, which recruit inflammatory cells to the infected tissue. Resident and recruited immune cells act together to eradicate bacteria from the bladder and to develop lasting immune memory against infection. However, urinary tract infection (UTI) is commonly recurrent, suggesting that the induction of a memory response in the bladder is inadequate to prevent reinfection. Additionally, infection seems to induce long-lasting changes in the urothelium, which can render the tissue more susceptible to future infection. The innate immune response is well-studied in the field of UTI, but considerably less is known about how adaptive immunity develops and how repair mechanisms restore bladder homeostasis following infection. Furthermore, data demonstrate that sex-based differences in immunity affect resolution and infection can lead to tissue remodelling in the bladder following resolution of UTI. To combat the rise in antimicrobial resistance, innovative therapeutic approaches to bladder infection are currently in development. Improving our understanding of how the bladder responds to infection will support the development of improved treatments for UTI, particularly for those at risk of recurrent infection.
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Affiliation(s)
- Livia Lacerda Mariano
- Department of Immunology, Institut Pasteur, Paris, France.,Inserm, U1223, Paris, France
| | - Molly A Ingersoll
- Department of Immunology, Institut Pasteur, Paris, France. .,Inserm, U1223, Paris, France.
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The Frequency of PAI, aer and traT Genes in Escherichia coli Commensal and Urinary Pathogenic E. coli Isolates in Shahrekord and the Relationship Between the Two Groups by Multiplex PCR. Jundishapur J Microbiol 2020. [DOI: 10.5812/jjm.98683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Nosocomial infections are acquired during hospital treatment or in a hospital environment. One such infecting agent is uropathogenic Escherichia coli and many virulence genes enable it to become pathogenic, thereby causing damage to the host. Objectives: This study aimed to identify aer, traT, and PAI genes in E. coli isolates collected from fecal and urinary tract infection (UTI) specimens and determine the relationship between them in both populations studied in a center in Iran by multiplex polymerase chain reaction (PCR) assay. Methods: Seventy-five isolates of E. coli from the urine of inpatients and 75 isolates from commensal fecal without UTI and diarrhea were collected. The E. coli bacteria were detected and isolated, using biochemical techniques and supplementary tests in the Microbiology Laboratory of Shahrekord University of Medical Sciences. Antibiotic susceptibility pattern for 14 antibiotics was done utilizing the disc diffusion method. The existence of aer, traT, and PAI virulence genes among all isolates was investigated by multiplex PCR. Results: Among the urinary pathogenic E. coli isolates, the highest antibiotic resistance was observed in cefazolin, ampicillin, and cotrimoxazole antibiotics. The prevalence rates of aer, traT, and PAI genes in the fecal isolates were 92%, 90.6%, and 46.6%, respectively. Further, their prevalence rates in urine isolates were 96%, 97.3%, and 41.3%, in that order. Conclusions: The presence of the high frequency of pathogenic islands (PAIs), especially in fecal samples, is important because these genes are easily transmitted and convert a commensal bacterium into a pathogen. Because only the genome of pathogenic bacteria has been unwrapped, little attention has been paid to PAIs in commensal bacteria.
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Halaji M, Feizi A, Mirzaei A, Sedigh Ebrahim-Saraie H, Fayyazi A, Ashraf A, Havaei SA. The Global Prevalence of Class 1 Integron and Associated Antibiotic Resistance in Escherichia coli from Patients with Urinary Tract Infections, a Systematic Review and Meta-Analysis. Microb Drug Resist 2020; 26:1208-1218. [PMID: 32282274 DOI: 10.1089/mdr.2019.0467] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Objectives: The present systematic review and meta-analysis study aimed to investigate the prevalence of class 1 integrons and their associated antibiotic resistance in uropathogenic Escherichia coli. Materials and Methods: A systematic search was conducted to identify studies meeting our inclusion criteria in the Web of Science, PubMed, Embase, Scopus, and Google Scholar electronic databases to the end of July 2019. Finally, 35 articles were selected for data extraction, and meta-analysis was performed using the metaprop program in the STATA, version 11.0, software. Results: The pooled prevalence of class 1 integrons was 47% (95% confidence interval [CI]: 40-54), ranging from 6% to 90%. There was significant heterogeneity among the 35 studies (χ2 = 840.37; p < 0.001; I2 = 95.95%). The results of the subgroup analysis based on characterization of patients indicated that pooled prevalence of class 1 integrons was 52% (95% CI: 41-63; n = 14 studies) and 43% (95% CI: 34-54; n = 19 studies) in hospitalized and community patients, respectively. The lowest and highest prevalence of antibiotic resistance was observed for imipenem and ampicillin, respectively. According to the results of Begg's and Egger's tests, we did not find significant publication bias both in the included studies and in the subgroup analysis. Conclusions: The results show the high prevalence of class 1 integrons and high level of antibiotic resistance in association with those among uropathogenic E. coli. Moreover, the prevalence of class 1 integrons in Asian countries, as well as hospital-acquired urinary tract infection (UTI), was higher than in other countries and community-acquired UTI.
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Affiliation(s)
- Mehrdad Halaji
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.,Clinical Research Development Unit of Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran
| | - Awat Feizi
- Department of Biostatistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Arezoo Mirzaei
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hadi Sedigh Ebrahim-Saraie
- Razi Clinical Research Development Center, Razi Hospital, Guilan University of Medical Sciences, Rasht, Iran
| | - Amirhossein Fayyazi
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ali Ashraf
- Clinical Research Development Unit of Poursina Hospital, Guilan University of Medical Sciences, Rasht, Iran
| | - Seyed Asghar Havaei
- Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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13
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Ramuta TŽ, Starčič Erjavec M, Kreft ME. Amniotic Membrane Preparation Crucially Affects Its Broad-Spectrum Activity Against Uropathogenic Bacteria. Front Microbiol 2020; 11:469. [PMID: 32265889 PMCID: PMC7107013 DOI: 10.3389/fmicb.2020.00469] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 03/04/2020] [Indexed: 12/26/2022] Open
Abstract
Urinary tract infections are among the most common bacterial infections in humans. Moreover, they are highly recurrent and increasingly often resistant to antibiotics. The antimicrobial properties of the amniotic membrane (AM), the innermost layer of fetal membranes, have been briefly reported in the literature, however, the results of published studies are often inconsistent and unclear; moreover, its effect on uropathogenic bacteria has not yet been investigated. Further, there is no data in the literature about the effect of AM preparation and storage on its antimicrobial properties. To examine the impact of several preparation procedures on the antimicrobial properties of AM, we prepared patches and homogenates of fresh (fAM) and cryopreserved (cAM) human AM and tested them on 14 selected Gram-positive and Gram-negative uropathogenic bacteria. By employing novel antimicrobial efficiency assays we showed that fAM and cAM homogenates have broad-spectrum antimicrobial activity against all here tested uropathogenic bacteria, except for Serratia marcescens. Moreover, they had a potent effect also on the multiple-resistant clinical strains of uropathogenic Escherichia coli. Interestingly, the patches of fAM and cAM had no antimicrobial effect on any of the tested strains. We therefore prepared and stored AM patches according to the standard procedure for clinical use in ophthalmology, which includes the cryopreservation of antibiotic-treated AM, and performed antimicrobial efficiency assays. Our findings suggest that the ultrastructure of AM patches could enable the retention of added antibiotics. In addition, we also prepared gentamicin-resistant uropathogenic E. coli strains, which confirmed that the antimicrobial effect of antibiotic-treated AM patches can be attributed to the antibiotic alone. To summarize, here we describe novel protocols for preparation and storage of AM to ensure the preservation of its antimicrobial factors. Moreover, we describe the mechanism of AM retention of antibiotics, based on which the AM could potentially be used as a drug delivery vehicle in future clinically applicable approaches.
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Affiliation(s)
- Taja Železnik Ramuta
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | | | - Mateja Erdani Kreft
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
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The Locus of Heat Resistance Confers Resistance to Chlorine and Other Oxidizing Chemicals in Escherichia coli. Appl Environ Microbiol 2020; 86:AEM.02123-19. [PMID: 31811037 DOI: 10.1128/aem.02123-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/28/2019] [Indexed: 12/20/2022] Open
Abstract
Some chlorine-resistant Escherichia coli isolates harbor the locus of heat resistance (LHR), a genomic island conferring heat resistance. In this study, the protective effect of the LHR for cells challenged by chlorine and oxidative stress was quantified. Cloning of the LHR protected against NaClO (32 mM; 5 min), H2O2 (120 mM; 5 min), and peroxyacetic acid (105 mg/liter; 5 min) but not against 5.8 mM KIO4, 10 mM acrolein, or 75 mg/liter allyl isothiocyanate. The lethality of oxidizing treatments for LHR-negative strains of E. coli was about 2 log10 CFU/ml higher than that for LHR-positive strains of E. coli The oxidation of cytoplasmic proteins and membrane lipids was quantified with the fusion probe roGFP2-Orp1 and the fluorescent probe BODIPY581/591, respectively. The fragment of the LHR coding for heat shock proteins protected cytoplasmic proteins but not membrane lipids against oxidation. The middle fragment of the LHR protected against the oxidation of membrane lipids but not of cytoplasmic proteins. The addition of H2O2, NaClO, and peroxyacetic acid also induced green fluorescent protein (GFP) expression in the oxidation-sensitive reporter strain E. coli O104:H4 Δstx 2::gfp::amp Cloning of pLHR reduced phage induction in E. coli O104:H4 Δstx 2::gfp::amp after treatment with oxidizing chemicals. Screening of 160 strains of Shiga toxin-producing E. coli (STEC) revealed that none of them harbors the LHR, additionally suggesting that the LHR and Stx prophages are mutually exclusive. Taking our findings together, the contribution of the LHR to resistance to chlorine and oxidative stress is based on the protection of multiple cellular targets by different proteins encoded by the genetic island.IMPORTANCE Chlorine treatments are used in water and wastewater sanitation; the resistance of Escherichia coli to chlorine is thus of concern to public health. We show that a genetic island termed the locus of heat resistance (LHR) protects E. coli not only against heat but also against chlorine and other oxidizing chemicals, adding to our knowledge of the tools used by E. coli to resist stress. Specific detection of the oxidation of different cellular targets in combination with the cloning of fragments of the LHR provided insight into mechanisms of protection and demonstrated that different fragments of the LHR protect different cellular targets. In E. coli, the presence of the LHR virtually always excluded other virulence factors. It is tempting to speculate that the LHR is maintained by strains of E. coli with an environmental lifestyle but is excluded by pathogenic strains that adapted to interact with vertebrate hosts.
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Padgen MR, Lera MP, Parra MP, Ricco AJ, Chin M, Chinn TN, Cohen A, Friedericks CR, Henschke MB, Snyder TV, Spremo SM, Wang JH, Matin AC. EcAMSat spaceflight measurements of the role of σ s in antibiotic resistance of stationary phase Escherichia coli in microgravity. LIFE SCIENCES IN SPACE RESEARCH 2020; 24:18-24. [PMID: 31987476 DOI: 10.1016/j.lssr.2019.10.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/07/2019] [Accepted: 10/19/2019] [Indexed: 05/22/2023]
Abstract
We report the results of the EcAMSat (Escherichia coli Antimicrobial Satellite) autonomous space flight experiment, investigating the role of σs in the development of antibiotic resistance in uropathogenic E. coli (UPEC) in microgravity (µ-g). The presence of σs, encoded by the rpoS gene, has been shown to increase antibiotic resistance in Earth gravity, but it was unknown if this effect occurs in µ-g. Two strains, wildtype (WT) UPEC and its isogenic ΔrpoS mutant, were grown to stationary phase aboard EcAMSat, an 11-kg small satellite, and in a parallel ground-based control experiment; cell growth rates for the two strains were found to be unaltered by µ-g. After starvation for over 24 h, stationary-phase cells were incubated with three doses of gentamicin (Gm), a common treatment for urinary tract infections (which have been reported in astronauts). Cellular metabolic activity was measured optically using the redox-based indicator alamarBlue (aB): both strains exhibited slower metabolism in µ-g, consistent with results from previous smallsat missions. The results also showed that µ-g did not enhance UPEC resistance to Gm; in fact, both strains were more susceptible to Gm in µ-g. It was also found, via a second ground-control experiment, that multi-week storage in the payload hardware stressed the cells, potentially obscuring small differential effects of the antibiotic between WT and mutant and/or between µ-g and ground. Overall, results showed that the ∆rpoS mutant was 34-37% less metabolically active than the WT for four different sets of conditions: ground without Gm, ground with Gm; µ-g without Gm, µ-g with Gm. We conclude therefore that the rpoS gene and its downstream products are important therapeutic targets for treating bacterial infections in space, much as they are on the ground.
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Affiliation(s)
| | - Matthew P Lera
- NASA Ames Research Center, Moffett Field, CA, United States
| | | | | | - Matthew Chin
- NASA Ames Research Center, Moffett Field, CA, United States
| | - Tori N Chinn
- NASA Ames Research Center, Moffett Field, CA, United States
| | - Aaron Cohen
- NASA Ames Research Center, Moffett Field, CA, United States
| | | | | | | | | | - Jing-Hung Wang
- Department of Microbiology & Immunology, Stanford School of Medicine, Stanford, CA, United States
| | - A C Matin
- Department of Microbiology & Immunology, Stanford School of Medicine, Stanford, CA, United States.
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Al-Hammadi MA, Al-Shamahy HA, Ali AQ, Abdulghani MAM, Pyar H, Al-Suboal I. Class 1 Integrons in Clinical Multi Drug Resistance <i>E. coli</i>, Sana'a Hospitals, Yemen. Pak J Biol Sci 2020; 23:231-239. [PMID: 31944083 DOI: 10.3923/pjbs.2020.231.239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND AND OBJECTIVES The occurrence of multi-drug resistance (MDR) Escherichia coli is one responsible for raised mortality and morbidity and was reported as major health problem. Class 1 integrons has crucial role in distributing antibiotic resistance genes among bacteria. Present work was aimed to determine the prevalence of class 1 integrons and its association with antibiotic resistance in MDR E. coli isolated from patient's body fluid and tissues from 6 health centers in Sana'a, Yemen. MATERIALS AND METHODS A cross-sectional study a total of 198 E. coli from patients diagnosed with infection that had been referred to 6 hospitals and medical diagnostic from July, 2017 to August, 2017 in Sana'a, Yemen. Susceptibility of E. coli isolates to 15 antibiotics using the disc diffusion method. Conventional polymerase chain reaction was used for detection of class 1 of integrons in 100 randomly selected MDR E. coli. RESULTS Overall 174 (87.9%) of 198 E. coli isolates were MDR. Class 1 integrons were detected in 67% of the randomly selected 100 of 198 MDR E. coli. A significant range (p<0.05-p<0.0001) was identified between presence of class 1 integrons and resistance to ceftriaxone, aztreonam, cefepime, amoxicillin-clavulanic acid, cefotoxime, cefepime-clavulanic acid, ceftazidime-clavulanic acid, ciprofloxacin, ceftazidime, norfloxacin and trimethoprim-sulfamethoxazole, while no significant difference were identified between integron class 1 and resistance to gentamicin, amikacin, nitrofurantoin and imipenem. CONCLUSION High MDR E. coli isolates were detected in this study, among them the prevalence of class 1 integrons is the most common. The significant association between class 1 integrons and resistance to common prescribed antibiotics in hospitals in Sana'a, Yemen.
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Anti-Adhesive Effect of ZnO Nanoparticles Against Uropathogenic Escherichia coli in Bladder Epithelial Cell Cultures and on fimH Gene Expression. Jundishapur J Microbiol 2019. [DOI: 10.5812/jjm.86885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Bacterial Microcompartment-Mediated Ethanolamine Metabolism in Escherichia coli Urinary Tract Infection. Infect Immun 2019; 87:IAI.00211-19. [PMID: 31138611 PMCID: PMC6652756 DOI: 10.1128/iai.00211-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/16/2019] [Indexed: 12/23/2022] Open
Abstract
Urinary tract infections (UTIs) are common and in general are caused by intestinal uropathogenic Escherichia coli (UPEC) ascending via the urethra. Microcompartment-mediated catabolism of ethanolamine, a host cell breakdown product, fuels the competitive overgrowth of intestinal E. coli, both pathogenic enterohemorrhagic E. coli and commensal strains. During a UTI, urease-negative E. coli bacteria thrive, despite the comparative nutrient limitation in urine. Urinary tract infections (UTIs) are common and in general are caused by intestinal uropathogenic Escherichia coli (UPEC) ascending via the urethra. Microcompartment-mediated catabolism of ethanolamine, a host cell breakdown product, fuels the competitive overgrowth of intestinal E. coli, both pathogenic enterohemorrhagic E. coli and commensal strains. During a UTI, urease-negative E. coli bacteria thrive, despite the comparative nutrient limitation in urine. The role of ethanolamine as a potential nutrient source during UTIs is understudied. We evaluated the role of the metabolism of ethanolamine as a potential nitrogen and carbon source for UPEC in the urinary tract. We analyzed infected urine samples by culture, high-performance liquid chromatography, reverse transcription-quantitative PCR, and genomic sequencing. The ethanolamine concentration in urine was comparable to the concentration of the most abundant reported urinary amino acid, d-serine. Transcription of the eut operon was detected in the majority of urine samples containing E. coli screened. All sequenced UPEC strains had conserved eut operons, while metabolic genotypes previously associated with UTI (dsdCXA, metE) were mainly limited to phylogroup B2. In vitro ethanolamine was found to be utilized as a sole source of nitrogen by UPEC strains. The metabolism of ethanolamine in artificial urine medium (AUM) induced metabolosome formation and provided a growth advantage at the physiological levels found in urine. Interestingly, eutE (which encodes acetaldehyde dehydrogenase) was required for UPEC strains to utilize ethanolamine to gain a growth advantage in AUM, suggesting that ethanolamine is also utilized as a carbon source. These data suggest that urinary ethanolamine is a significant additional carbon and nitrogen source for infecting E. coli strains.
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Xicohtencatl-Cortes J, Cruz-Córdova A, Cázares-Domínguez V, Escalona-Venegas G, Zavala-Vega S, Arellano-Galindo J, Romo-Castillo M, Hernández-Castro R, Ochoa SA, Luna-Pineda VM. Uropathogenic Escherichia coli strains harboring tosA gene were associated to high virulence genes and a multidrug-resistant profile. Microb Pathog 2019; 134:103593. [PMID: 31195111 DOI: 10.1016/j.micpath.2019.103593] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 02/06/2023]
Abstract
TosA, a putative repeats-in-toxin protein that has recently gained importance as an antigenic molecule, has characteristics of nonfimbrial adhesins and can act as a virulence marker in uropathogenic Escherichia coli (UPEC) strains; however, little is known about the association of this protein with antibiotic resistance profiles in UPEC tosA+ clinical strains. The aim of this study was to evaluate UPEC tosA+ strains, including examining genetic diversity, associations with phylogenetic groups, resistance profiles, virulence genes, adherence assays, integrons, and extended-spectrum beta-lactamase phenotypes. Pulsed-field gel electrophoresis analysis grouped these strains into eight clusters with 62% genetic diversity. These strains were mainly associated with the multidrug-resistant profiles, together with an association with class 1 integron and the extended-spectrum beta-lactamase phenotype. Additionally, the strains exhibited a distribution of ≥96% for core-associated genes, while a variable distribution was identified for pathogenic islands-associated genes. Strong associations between UPEC tosA+ strains and two phylogenetic groups (B2 and D) were identified, including resistance to β-lactam and non-β-lactam antibiotics. The UPEC tosA+ clinical strains exhibited major adherence, which was related to the fitness and virulence genes. A recombinant TosA protein reacted with antibodies from the sera of urinary tract infection patients, and anti-recombinant TosA polyclonal antibodies also detected TosA expression in these strains. In conclusion, strains of UPEC tosA+ belonging to phylogenetic group B2 had a high frequency of fitness and virulence genes associated with class 1 integrons and the extended-spectrum beta-lactamase phenotype, which exhibited a high adherence profile. The TosA protein is expressed during infection with UPEC and is considered an immunogenic molecule.
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Affiliation(s)
- Juan Xicohtencatl-Cortes
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico.
| | - Ariadnna Cruz-Córdova
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico
| | - Vicenta Cázares-Domínguez
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico
| | - Gerardo Escalona-Venegas
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico
| | - Sergio Zavala-Vega
- Laboratorio de Neuropatología, Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez", Ciudad de México, Mexico; Departamento de Infectología, Hospital Infantil de México "Federico Gómez", Ciudad de México, Mexico
| | - José Arellano-Galindo
- Departamento de Infectología, Hospital Infantil de México "Federico Gómez", Ciudad de México, Mexico
| | - Mariana Romo-Castillo
- CONACyT-IMSS, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Ciudad de México, Mexico
| | - Rigoberto Hernández-Castro
- Departamento de Ecología de Agentes Patógenos, Hospital General "Dr. Manuel Gea González", Ciudad de México, Mexico
| | - Sara A Ochoa
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico.
| | - Víctor M Luna-Pineda
- Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México "Federico Gómez", Cuauhtémoc, Ciudad de México, Mexico.
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Schreiber HL, Conover MS, Chou WC, Hibbing ME, Manson AL, Dodson KW, Hannan TJ, Roberts PL, Stapleton AE, Hooton TM, Livny J, Earl AM, Hultgren SJ. Bacterial virulence phenotypes of Escherichia coli and host susceptibility determine risk for urinary tract infections. Sci Transl Med 2017; 9:9/382/eaaf1283. [PMID: 28330863 DOI: 10.1126/scitranslmed.aaf1283] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 05/12/2016] [Accepted: 12/12/2016] [Indexed: 01/01/2023]
Abstract
Urinary tract infections (UTIs) are caused by uropathogenic Escherichia coli (UPEC) strains. In contrast to many enteric E. coli pathogroups, no genetic signature has been identified for UPEC strains. We conducted a high-resolution comparative genomic study using E. coli isolates collected from the urine of women suffering from frequent recurrent UTIs. These isolates were genetically diverse and varied in their urovirulence, that is, their ability to infect the bladder in a mouse model of cystitis. We found no set of genes, including previously defined putative urovirulence factors (PUFs), that were predictive of urovirulence. In addition, in some patients, the E. coli strain causing a recurrent UTI had fewer PUFs than the supplanted strain. In competitive experimental infections in mice, the supplanting strain was more efficient at colonizing the mouse bladder than the supplanted strain. Despite the lack of a clear genomic signature for urovirulence, comparative transcriptomic and phenotypic analyses revealed that the expression of key conserved functions during culture, such as motility and metabolism, could be used to predict subsequent colonization of the mouse bladder. Together, our findings suggest that UTI risk and outcome may be determined by complex interactions between host susceptibility and the urovirulence potential of diverse bacterial strains.
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Affiliation(s)
- Henry L Schreiber
- Department of Molecular Microbiology, Washington University, St. Louis, MO 63110, USA.,Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142, USA
| | - Matt S Conover
- Department of Molecular Microbiology, Washington University, St. Louis, MO 63110, USA
| | - Wen-Chi Chou
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142, USA
| | - Michael E Hibbing
- Department of Molecular Microbiology, Washington University, St. Louis, MO 63110, USA
| | - Abigail L Manson
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142, USA
| | - Karen W Dodson
- Department of Molecular Microbiology, Washington University, St. Louis, MO 63110, USA
| | - Thomas J Hannan
- Department of Pathology and Immunology, Washington University, St. Louis, MO 63110, USA
| | - Pacita L Roberts
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Ann E Stapleton
- Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Thomas M Hooton
- Division of Infectious Diseases, Department of Medicine, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Jonathan Livny
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142, USA.
| | - Ashlee M Earl
- Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142, USA.
| | - Scott J Hultgren
- Department of Molecular Microbiology, Washington University, St. Louis, MO 63110, USA. .,Center for Women's Infectious Disease Research, Washington University, St. Louis, MO 63110, USA
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Kumar N, Nahid F, Zahra R. Association of virulence factors, phylogenetic groups and antimicrobial resistance markers in Escherichia coli from Badin city, Pakistan. J Chemother 2016; 29:8-13. [PMID: 27077934 DOI: 10.1080/1120009x.2016.1154682] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Escherichia coli, the most frequent cause of UTIs has extensive genetic substructure and can be assigned to eight phylogroups, A, B1, B2, C, D, E, F and Escherichia cryptic clade I. We investigated the distribution of virulence determinants and antimicrobial resistance genes in relation to phylogenetic groups. METHODS A total of 77 E. coli isolates were collected from Civil Hospital Badin, Pakistan. Isolates were assigned phylogroups using quadruplex PCR method, while virulence and antibiotic resistance genes, blaCTX-M and blaNDM-1 were also detected using PCR. RESULTS Thirty-four isolates were assigned to group B2, while 23, 2, 1, 7 and 10 isolates were assigned to F, B1, A/C, clade I/II and negative, respectively. Among virulence genes, prevalence of papC (83%) was highest followed by aer (57%), papGII (16%), papGIII (14%), cnf (9%), hly (5%) and sfa (6%). Of these isolates, 23% and 9% were positive for blaCTX-M and blaNDM-1, respectively.
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Affiliation(s)
- Neeraj Kumar
- a Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Fouzia Nahid
- a Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
| | - Rabaab Zahra
- a Department of Microbiology , Quaid-i-Azam University , Islamabad , Pakistan
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Hadifar S, Moghoofei M, Nematollahi S, Ramazanzadeh R, Sedighi M, Salehi-Abargouei A, Miri A. Epidemiology of Multidrug Resistant Uropathogenic Escherichia coli in Iran: a Systematic Review and Meta-Analysis. Jpn J Infect Dis 2016; 70:19-25. [PMID: 27000462 DOI: 10.7883/yoken.jjid.2015.652] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Urinary tract infection (UTI) is one of the most common infections in humans. It is primarily caused by uropathogenic Escherichia coli (UPEC), which has a high multidrug resistance (MDR). In consideration of the prevalence of MDR-UPEC strains, the aims of the present study were to systematically review the published data about the prevalence rate of MDR-UPEC from different parts of Iran and to establish the overall relative frequency (RF) of these strains in Iran. We searched several databases including PubMed, ISI Web of Science, Scopus, Google Scholar, IranMedex, and Iranian Scientific Information Database by using the following keywords: "Escherichia coli", "multidrug resistant", "MDR", "urinary tract infections", "UTI", "uropathogenic". and "Iran". Articles or abstracts that reported the prevalence of MDR-UPEC were included in this review. We found 15 articles suitable for inclusion in this study. A pooled estimation of 10,247 UPEC strains showed that 49.4% (95% confidence interval = 48.0-50.7%) of the stranis were MDR positive. The RF of MDR-UPEC in different studies varied from 10.5% to 79.2% in the Kashan and Hamedan provinces, respectively. According to the results of the present study, the RF of MDR-UPEC in Iran is high. Thus, measures should be taken to keep the emergence and transmission of these strains to a minimum.
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Affiliation(s)
- Shima Hadifar
- Department of Microbiology, Pasteur Institute of Tehran
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Starčič Erjavec M, Petkovšek Ž, Kuznetsova MV, Maslennikova IL, Žgur-Bertok D. Strain ŽP - the first bacterial conjugation-based "kill"-"anti-kill" antimicrobial system. Plasmid 2015; 82:28-34. [PMID: 26436830 DOI: 10.1016/j.plasmid.2015.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/28/2015] [Accepted: 10/01/2015] [Indexed: 01/18/2023]
Abstract
As multidrug resistant bacteria pose one of the greatest risks to human health new alternative antibacterial agents are urgently needed. One possible mechanism that can be used as an alternative to traditional antibiotic therapy is transfer of killing agents via conjugation. Our work was aimed at providing a proof of principle that conjugation-based antimicrobial systems are possible. We constructed a bacterial conjugation-based "kill"-"anti-kill" antimicrobial system employing the well known Escherichia coli probiotic strain Nissle 1917 genetically modified to harbor a conjugative plasmid carrying the "kill" gene (colicin ColE7 activity gene) and a chromosomally encoded "anti-kill" gene (ColE7 immunity gene). The constructed strain acts as a donor in conjugal transfer and its efficiency was tested in several types of conjugal assays. Our results clearly demonstrate that conjugation-based antimicrobial systems can be highly efficient.
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Affiliation(s)
- Marjanca Starčič Erjavec
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia.
| | - Živa Petkovšek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia.
| | - Marina V Kuznetsova
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Science, 13 Golev Street, 614081 Perm, Russia.
| | - Irina L Maslennikova
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Science, 13 Golev Street, 614081 Perm, Russia.
| | - Darja Žgur-Bertok
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia.
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Ghaderpour A, Ho WS, Chew LL, Bong CW, Chong VC, Thong KL, Chai LC. Diverse and abundant multi-drug resistant E. coli in Matang mangrove estuaries, Malaysia. Front Microbiol 2015; 6:977. [PMID: 26483759 PMCID: PMC4586456 DOI: 10.3389/fmicb.2015.00977] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 09/02/2015] [Indexed: 01/09/2023] Open
Abstract
E.coli, an important vector distributing antimicrobial resistance in the environment, was found to be multi-drug resistant, abundant, and genetically diverse in the Matang mangrove estuaries, Malaysia. One-third (34%) of the estuarine E. coli was multi-drug resistant. The highest antibiotic resistance prevalence was observed for aminoglycosides (83%) and beta-lactams (37%). Phylogenetic groups A and B1, being the most predominant E. coli, demonstrated the highest antibiotic resistant level and prevalence of integrons (integron I, 21%; integron II, 3%). Detection of phylogenetic group B23 downstream of fishing villages indicates human fecal contamination as a source of E. coli pollution. Enteroaggregative E. coli (1%) were also detected immediately downstream of the fishing village. The results indicated multi-drug resistance among E. coli circulating in Matang estuaries, which could be reflective of anthropogenic activities and aggravated by bacterial and antibiotic discharges from village lack of a sewerage system, aquaculture farms and upstream animal husbandry.
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Affiliation(s)
- Aziz Ghaderpour
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Wing Sze Ho
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia
| | - Li-Lee Chew
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Chui Wei Bong
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Ving Ching Chong
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Kwai-Lin Thong
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
| | - Lay Ching Chai
- Faculty of Science, Institute of Biological Science, University of Malaya Kuala Lumpur, Malaysia ; Institute of Ocean and Earth Sciences, University of Malaya Kuala Lumpur, Malaysia
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Abstract
ABSTRACT
Antimicrobial agents of various types have important bearing on the outcomes of microbial infections. These agents may be bacteriostatic or –cidal, exert their impact via various means, originate from a living organism or a laboratory, and appropriately be used in or on living tissue or not. Though the primary focus of this chapter is on resistance to the antimicrobial agents used to treat uropathogenic
Escherichia coli
(UPEC)-caused urinary tract infections (UTIs), some attention will be given to UPEC’s resistance to silver-containing antiseptics, which may be incorporated into catheters to prevent foreign body-associated UTIs.
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Derakhshandeh A, Firouzi R, Motamedifar M, Arabshahi S, Novinrooz A, Boroojeni AM, Bahadori M, Heidari S. Virulence Characteristics and Antibiotic Resistance Patterns among Various Phylogenetic Groups of Uropathogenic Escherichia coli Isolates. Jpn J Infect Dis 2015; 68:428-31. [PMID: 25866111 DOI: 10.7883/yoken.jjid.2014.327] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to determine the resistance patterns of uropathogenic Escherichia coli (UPEC) isolates and to investigate the frequency of several virulence genes, including fimH, papA, hlyD, cnf-1, sitA, and tsh, among various phylogenetic groups of UPEC isolates. A total of 85 E. coli isolates were recovered from urine samples from outpatients with a clinical diagnosis of uncomplicated urinary tract infections. A molecular approach to examine the antimicrobial resistance patterns was employed using PCR and the disc diffusion method. The detected frequencies of the virulence factor genes determined using PCR were: fimH (34.1%), papA (9.4%), hlyD (21.2%), cnf-1 (3.5%), sitA (15.3%), and tsh (27.1%). These results revealed that the isolates were resistant to trimethoprim-sulfamethoxazole (SXT) (74.1%), cefotaxime (CTX) (68.2%), and amoxicillin-clavulanic acid (AMC) (94.1%), and they were relatively less resistant to N (56.5%). According to these results, further investigation is needed to determine exactly whether or not SXT, CTX, and AMC are appropriate antibiotics for the treatment of UPEC infections in southern Iran. Although these results demonstrate that fimH is the most frequent virulence gene among UPEC isolates, the high prevalence of isolates that do not encode fimH (75.9%) and the relatively low frequency of isolates that carry other virulence genes require further investigation to clarify the role of the other potential virulence factors in the pathogenesis of these isolates.
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Adel El-Sokkary MM, Abdelmegeed ES. Characterisation of Class 1 Integron among <i>Escherichia coli</i> Isolated from Mansoura University Hospitals in Egypt. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/aim.2015.54025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Derakhshandeh A, Firouzi R, Motamedifar M, Motamedi Boroojeni A, Bahadori M, Arabshahi S, Novinrooz A, Heidari S. Distribution of virulence genes and multiple drug-resistant patterns amongst different phylogenetic groups of uropathogenic Escherichia coli isolated from patients with urinary tract infection. Lett Appl Microbiol 2014; 60:148-154. [PMID: 25355175 DOI: 10.1111/lam.12349] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 10/12/2014] [Accepted: 10/22/2014] [Indexed: 12/29/2022]
Abstract
A total of 85 Uropathogenic Escherichia coli (UPEC) isolates were screened against ceftiofur, oxacillin, nitrofurantoin and lincospectin using Kirby-Bauer disc diffusion method, following CLSI guidelines. Prevalence of virulent factor genes amongst the isolates was determined by PCR, using gene-specific primers against the different virulent factors. Statistical analysis of the data was performed using SPSS software. The prevalence of traT, ompT, Iss, malX and ibeA genes was 47.1%, 38.8%, 20%, 16.5% and 9.4%, respectively. The most prevalent gene in group A and D was traT, whilst in group B2 was Iss. The highest resistance has been shown against oxacillin (98.8%), followed by ceftiofur (77.6%), whilst resistance to lincospectin (2.4%) and nitrofurantoin (12.9%) had the lowest frequencies. Multidrug resistance was shown in 82.35% of the isolates, whilst this study recommend lincospectin and nitrofurantoin as choice drugs for treatment, but more investigation of the bacterial pathogenicity associated with urinary tract infection (UTI) may contribute to a better medical intervention.
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Affiliation(s)
- A Derakhshandeh
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - R Firouzi
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - M Motamedifar
- Department of Bacteriology & Virology, Shiraz Medical School, Shiraz University of Medical Sciences, Shiraz, Iran
| | - A Motamedi Boroojeni
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - M Bahadori
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - S Arabshahi
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - A Novinrooz
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - S Heidari
- Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
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Kargar M, Mohammadalipour Z, Doosti A, Lorzadeh S, Japoni-Nejad A. High Prevalence of Class 1 to 3 Integrons Among Multidrug-Resistant Diarrheagenic Escherichia coli in Southwest of Iran. Osong Public Health Res Perspect 2014; 5:193-8. [PMID: 25379369 PMCID: PMC4215003 DOI: 10.1016/j.phrp.2014.06.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Revised: 06/17/2014] [Accepted: 06/17/2014] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES Horizontal transfer of integrons is one of the important factors that can contribute to the occurrence of multidrug-resistant (MDR) bacteria. This study aimed to determine the prevalence of integrons among MDR Escherichia coli strains isolated from stool specimens and investigate the associations between the existence of integrons and MDR properties in the southwest of Iran. METHODS There were 164 E. coli strains isolated from January 2012 to June 2012. Fecal specimens identified as E. coli by the conventional methods. Subsequently the antibiotic resistance was assessed using Clinical and Laboratory Standard Institute criteria. The presence of class 1-3 integrons and embedded gene cassettes was verified using specific primers by multiplex polymerase chain reaction assay. RESULTS Among a total of 164 studied samples, 69 (42.07%) isolates were multidrug resistant. Class 1 and class 2 integrons were present in 78.26% and 76.81% MDR isolates, respectively. For the first time in Iran, class 3 integron was observed in 26.09% MDR isolates. Significant correlations were identified between: class 1 integron and resistance to amikacin, gentamicin, chloramphenicol, ampicillin, tetracycline, nalidixic acid, and co-trimoxazole; class 2 integron and resistance to aminoglycosides, co-trimoxazole, cefalexin, ampicillin, and chloramphenicol; and class 3 integron and resistance to gentamicin, kanamycin, and streptomycin. CONCLUSION Our results indicate that integrons are common among MDR isolates and they can be used as a marker for the identification of MDR isolates. Therefore, due to the possibility of a widespread outbreak of MDR isolates, molecular surveillance and sequencing of the integrons in other parts of the country is recommended.
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Affiliation(s)
- Mohammad Kargar
- Department of Microbiology, Jahrom Branch, Islamic Azad University, Jahrom, Iran
| | | | - Abbas Doosti
- Biotechnology Research Center, Islamic Azad University, Shahrekord Branch, Shahrekord, Iran
| | - Shahrokh Lorzadeh
- Biotechnology Research Center, Islamic Azad University, Shahrekord Branch, Shahrekord, Iran
| | - Alireza Japoni-Nejad
- Department of Mycobacteriology and Pulmonary Disease, Pasteur Institute of Iran, Tehran, Iran
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Kõljalg S, Truusalu K, Stsepetova J, Pai K, Vainumäe I, Sepp E, Mikelsaar M. TheEscherichia coliphylogenetic group B2 with integrons prevails in childhood recurrent urinary tract infections. APMIS 2013; 122:452-8. [DOI: 10.1111/apm.12167] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/27/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Siiri Kõljalg
- Department of Microbiology; University of Tartu; Tartu
| | - Kai Truusalu
- Department of Microbiology; University of Tartu; Tartu
| | | | - Kristiine Pai
- Department of Microbiology; University of Tartu; Tartu
| | - Inga Vainumäe
- Department ofPediatrics; University of Tartu; Tartu Estonia
| | - Epp Sepp
- Department of Microbiology; University of Tartu; Tartu
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Pereira A, Santos A, Tacão M, Alves A, Henriques I, Correia A. Genetic diversity and antimicrobial resistance of Escherichia coli from Tagus estuary (Portugal). THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 461-462:65-71. [PMID: 23714246 DOI: 10.1016/j.scitotenv.2013.04.067] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 04/23/2013] [Accepted: 04/23/2013] [Indexed: 06/02/2023]
Abstract
Fecal pollution of surface waters is a current world-wide public health concern and may contribute for the dissemination of antibiotic resistance. The Tagus estuary located in the south of Portugal is one of the largest wetlands in the west coast of Europe. In this study, water samples were collected from seven stations with different anthropic pressures along the estuary and evaluated for water quality indicator bacteria. Escherichia coli isolates (n=350) were typed by REP-PCR. Representatives of each REP profile (n=220) were evaluated phenotypically for resistance to 17 antibiotics and characterized in terms of phylogenetic group. Resistant isolates were screened for the presence of antibiotic resistance genes (tet(A), tet(B), sul1, sul2, qnrA, qnrB, qnrS, aacA4-cr, bla(TEM), bla(SHV), bla(CTX-M), bla(CMY-like), bla(IMP), bla(VIM)) and integrase genes (intI1 and intI2). The highest antibiotic resistance prevalence was observed for streptomycin and tetracycline followed by β-lactams and sulphonamides. Among E. coli isolates, 65.16% were resistant to at least one of the 17 antibiotics tested and approximately 19% were multiresistant. In our E. coli population phylo-groups A and D were predominant and characterized by higher prevalence of the antibiotic resistance. intI1 and intI2 genes were found in 12% of the isolates with prevalence of class 1 integrons. A strong correlation between the prevalence of integrons and multiresistance was observed. Differences in terms of antibiotic resistance between phylogenetic groups and between sampling sites were statistically significant. The results demonstrate a high prevalence of antibiotic resistance among E. coli circulating in the Tagus estuary with emphasis on the occurrence of resistance to last-resort antibiotics and on the high incidence of multiresistance.
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Affiliation(s)
- Anabela Pereira
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, Aveiro, Portugal
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Barguigua A, El Otmani F, Talmi M, Zerouali K, Timinouni M. Prevalence and types of extended spectrum β-lactamases among urinary Escherichia coli isolates in Moroccan community. Microb Pathog 2013; 61-62:16-22. [DOI: 10.1016/j.micpath.2013.04.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/10/2013] [Accepted: 04/23/2013] [Indexed: 11/25/2022]
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Mukherjee M, Basu S, Mukherjee SK, Majumder M. Multidrug-Resistance and Extended Spectrum Beta-Lactamase Production in Uropathogenic E. Coli which were Isolated from Hospitalized Patients in Kolkata, India. J Clin Diagn Res 2013; 7:449-53. [PMID: 23634394 DOI: 10.7860/jcdr/2013/4990.2796] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 11/18/2012] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND OBJECTIVE Urinary Tract Infections (UTIs) are mostly caused by Escherichia coli. The appropriate therapy demands a current knowledge on the antimicrobial susceptibility pattern amongst these pathogens, as an inappropriate use of antibiotics may lead to complications and treatment failure. The UTIs which are caused by multidrug resistant Extended-Spectrum Beta-Lactamase (ESBL) producing bacteria further pose a severe problem, as the treatment options are limited. The aim of this study was to identify the pattern of multi drug resistance amongst the uropathogenic E. coli (UPEC) isolates which were obtained from hospitalized patients. MATERIALS AND METHODS Forty UPEC were isolated from 200 urine samples of hospitalized patients who were clinically suspected for UTIs. Antimicrobial susceptibility screening was performed by using 16 antibiotics, by the Kirby Bauer disk diffusion technique. The isolates which were resistant to the third generation cephalosporins were subjected to the ESBL confirmatory test by using drug and drug-inhibitor combination disks by following the CLSI guidelines. RESULTS All the 40 isolates except three were multidrug resistant. They showed the highest sensitivities for nitrofurantoin (72.5%) and amikacin (70%). A high level of resistance was observed against ampicillin (97.5%), nalidixic acid and cefelexin (95%), amoxicillin (92.5%), cotrimoxazole (82.5%) and ciprofloxacin (80%) respectively. Thirty different antibiotic resistance patterns were observed against the different antibiotics. Twenty-eight out of the 40 isolates were resistant to the third generation cephalosporins. However, the phenotypic test for the ESBL confirmation indicated that eighteen out of the twenty-eight isolates were ESBL producers and that eleven different drug resistance patterns were observed amongst them. CONCLUSIONS Therefore, this study accounts for the varied multidrug resistance pattern amongst the uropathogenic E. coli which were isolated from hospitalized patients in Kolkata, an eastern region of India. Nitrofurantoin and amikacin should be assigned as potent drugs to treat this infection in this region of the country. These varied resistance patterns present major therapeutic and infection control challenges and they suggest a heterogeneous population of the uropathogenic E. coli isolates which circulate in this sector of India.
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Affiliation(s)
- Mandira Mukherjee
- Department of Biochemistry and Medical Biotechnology, Calcutta School of Tropical Medicine , Kolkata, West Bengal, India
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Budič M, Rijavec M, Petkovšek Ž, Žgur-Bertok D. Escherichia coli bacteriocins: antimicrobial efficacy and prevalence among isolates from patients with bacteraemia. PLoS One 2011; 6:e28769. [PMID: 22205967 PMCID: PMC3242755 DOI: 10.1371/journal.pone.0028769] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 11/15/2011] [Indexed: 11/23/2022] Open
Abstract
Bacteriocins are antimicrobial peptides generally active against bacteria closely related to the producer. Escherichia coli produces two types of bacteriocins, colicins and microcins. The in vitro efficacy of isolated colicins E1, E6, E7, K and M, was assessed against Escherichia coli strains from patients with bacteraemia of urinary tract origin. Colicin E7 was most effective, as only 13% of the tested strains were resistant. On the other hand, 32%, 33%, 43% and 53% of the tested strains exhibited resistance to colicins E6, K, M and E1. Moreover, the inhibitory activity of individual colicins E1, E6, E7, K and M and combinations of colicins K, M, E7 and E1, E6, E7, K, M were followed in liquid broth for 24 hours. Resistance against individual colicins developed after 9 hours of treatment. On the contrary, resistance development against the combined action of 5 colicins was not observed. One hundred and five E. coli strains from patients with bacteraemia were screened by PCR for the presence of 5 colicins and 7 microcins. Sixty-six percent of the strains encoded at least one bacteriocin, 43% one or more colicins, and 54% one or more microcins. Microcins were found to co-occur with toxins, siderophores, adhesins and with the Toll/Interleukin-1 receptor domain-containing protein involved in suppression of innate immunity, and were significantly more prevalent among strains from non-immunocompromised patients. In addition, microcins were highly prevalent among non-multidrug-resistant strains compared to multidrug-resistant strains. Our results indicate that microcins contribute to virulence of E. coli instigating bacteraemia of urinary tract origin.
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Affiliation(s)
- Maruška Budič
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Matija Rijavec
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Živa Petkovšek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Darja Žgur-Bertok
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
- * E-mail:
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Gündoğdu A, Long YB, Vollmerhausen TL, Katouli M. Antimicrobial resistance and distribution of sul genes and integron-associated intI genes among uropathogenic Escherichia coli in Queensland, Australia. J Med Microbiol 2011; 60:1633-1642. [DOI: 10.1099/jmm.0.034140-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Aycan Gündoğdu
- Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - Ysanne Beverley Long
- Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - Tara Leigh Vollmerhausen
- Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
| | - Mohammad Katouli
- Faculty of Science, Health and Education, University of the Sunshine Coast, Maroochydore DC, Queensland 4558, Australia
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Amalaradjou MAR, Narayanan A, Venkitanarayanan K. Trans-cinnamaldehyde decreases attachment and invasion of uropathogenic Escherichia coli in urinary tract epithelial cells by modulating virulence gene expression. J Urol 2011; 185:1526-31. [PMID: 21334666 DOI: 10.1016/j.juro.2010.11.078] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Indexed: 10/18/2022]
Abstract
PURPOSE Uropathogenic Escherichia coli is the primary bacterium causing urinary tract infection in humans. Attachment and invasion of urinary tract epithelial cells by UPEC is the first critical step in establishing a successful urinary tract infection. We investigated the efficacy of subinhibitory concentrations of trans-cinnamaldehyde to inhibit uropathogenic E. coli attachment and invasion of human uroepithelial cells. We also determined the trans-cinnamaldehyde effect on uropathogenic E. coli genes encoding virulence factors critical for uroepithelial cell bacterial attachment and invasion. MATERIALS AND METHODS Polystyrene 24-well plates seeded with uroepithelial cells were inoculated with uropathogenic E. coli (about 6.0 log cfu) and subinhibitory concentrations of trans-cinnamaldehyde (0, 325, 560 and 750 μM), and incubated for 60 minutes at 37C. Uroepithelial cells were washed and lysed to enumerate adhered uropathogenic E. coli populations. For the invasion assay uroepithelial cells were treated with gentamicin after incubation and lysed to enumerate invaded uropathogenic E. coli. Also, the trans-cinnamaldehyde effect on uropathogenic E. coli genes encoding attachment and invasion associated virulence factors was determined by real-time quantitative polymerase chain reaction. RESULTS Trans-cinnamaldehyde significantly decreased uroepithelial cell attachment and invasion by uropathogenic E. coli (p <0.05). Real-time quantitative polymerase chain reaction revealed that trans-cinnamaldehyde significantly decreased the expression of major genes involved in uropathogenic E. coli attachment and invasion of host tissue (p <0.05). The down-regulating effect of trans-cinnamaldehyde on these genes potentially translated into decreased ability of uropathogenic E. coli to attach and invade bladder cells. CONCLUSIONS Trans-cinnamaldehyde may potentially be used as a safe, effective antimicrobial to control uropathogenic E. coli infection. Followup studies in animal models are warranted.
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Figueira V, Serra E, Manaia CM. Differential patterns of antimicrobial resistance in population subsets of Escherichia coli isolated from waste- and surface waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2011; 409:1017-23. [PMID: 21215425 DOI: 10.1016/j.scitotenv.2010.12.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 11/19/2010] [Accepted: 12/03/2010] [Indexed: 05/24/2023]
Abstract
The species Escherichia coli comprises different subgroups with distinct phylogeny, physiology and ecology and, thus, presumably, with different roles in antimicrobial resistance dissemination. E. coli strains isolated from raw and treated municipal wastewater and from urban water streams were characterized in terms of phylogenetic groups, antimicrobial resistance patterns and the presence of class 1 and class 2 integrons. Our main objective was to investigate the contribution of the different phylo-groups in antimicrobial resistance dissemination in urban waters. Groups A and B1 were predominant in all types of water, evidencing, respectively, the lowest and the highest resistance prevalence. Municipal wastewater treatment was accompanied by significant increases of ciprofloxacin and streptomycin resistance (p<0.01). Antimicrobial resistance prevalence differed significantly between the different phylo-groups and within the same group, mainly in group A. Such differences contributed to explain the higher ciprofloxacin and streptomycin resistance rates observed in treated effluent in comparison with the raw wastewater. We conclude that the dynamics of the bacterial populations has a major role on the dissemination of antimicrobial resistance in the environment.
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Affiliation(s)
- Vânia Figueira
- CBQF/Escola Superior de Biotecnologia, Universidade Católica Portuguesa, 4200-072 Porto, Portugal
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Schwan WR, Briska A, Stahl B, Wagner TK, Zentz E, Henkhaus J, Lovrich SD, Agger WA, Callister SM, DuChateau B, Dykes CW. Use of optical mapping to sort uropathogenic Escherichia coli strains into distinct subgroups. MICROBIOLOGY-SGM 2010; 156:2124-2135. [PMID: 20378655 PMCID: PMC3068680 DOI: 10.1099/mic.0.033977-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Optical maps were generated for 33 uropathogenic Escherichia coli (UPEC) isolates. For individual genomes, the NcoI restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced E. coli and Shigella strains. All of the UPEC isolates clustered separately from the Shigella strains as well as the laboratory and enterohaemorrhagic E. coli strains. Moreover, the individual strains appeared to cluster into distinct subgroups based on the dendrogram analyses. Phylogenetic grouping of these 33 strains showed that 32/33 were the B2 subgroup and 1/33 was subgroup A. To further characterize the similarities and differences among the 33 isolates, pathogenicity island (PAI), haemolysin and virulence gene comparisons were performed. A strong correlation was observed between individual subgroups and virulence factor genes as well as haemolysis activity. Furthermore, there was considerable conservation of sequenced-strain PAIs in the specific subgroups. Strains with different antibiotic-resistance patterns also appeared to sort into separate subgroups. Thus, the optical maps distinguished the UPEC strains from other E. coli strains and further subdivided the strains into distinct subgroups. This optical mapping procedure holds promise as an alternative way to subgroup all E. coli strains, including those involved in infections outside of the intestinal tract and epidemic strains with distinct patterns of antibiotic resistance.
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Costa M, Drescher G, Maboni F, Weber S, Schrank A, Vainstein M, Schrank I, Vargas A. Virulence factors, antimicrobial resistance, and plasmid content of Escherichia coli isolated in swine commercial farms. ARQ BRAS MED VET ZOO 2010. [DOI: 10.1590/s0102-09352010000100004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Virulence factors and antimicrobial resistance patterns of Escherichia coli isolates were evaluated. A total of 80 E. coli isolates were evaluated, being 64 from clinical samples (intestinal content and fragments of organs from diarrheic piglets), seven from feces of clinically healthy piglets and sows, and nine environmental samples (five from facilities, two from feed, one from insect, and one from waste). Molecular characterization was performed by PCR detection of fimbriae and toxin genes and plasmid content determination. The isolates were also characterized according to their resistance or sensitivity to the following drugs: ampicillin, trimethoprim:sulfamethoxazole, tetracycline, amikacine, colistin, norfloxacin, florfenicol, enrofloxacin, cefalexin, trimethoprim, neomycin, chloramphenicol, and gentamicin. From 80 E. coli isolates, 53.8% were classified as enterotoxigenic E. coli (ETEC), 2.5% were shiga toxin-producing E. coli (STEC), and 43.8% showed a non specific pattern and were unclassified. One fecal isolate from non-diarrheic piglet was classified as ETEC by PCR. Clinical isolates showed resistance mainly for tetracycline and trimethoprim:sulfamethoxazole. Plasmidial DNA was observed in 70 isolates, being 78.5% of clinical isolates, 8.57% of non-diarrheic feces, and 12.8% of environment.
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Affiliation(s)
- M.M. Costa
- UFRGS; Universidade Federal do Vale do São Francisco
| | - G. Drescher
- Universidade Federal do Vale do São Francisco
| | - F Maboni
- Universidade Federal de Santa Maria
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Major differences exist in frequencies of virulence factors and multidrug resistance between community and nosocomial Escherichia coli bloodstream isolates. J Clin Microbiol 2010; 48:1099-104. [PMID: 20107091 DOI: 10.1128/jcm.02017-09] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli is a major cause of bloodstream infections and death due to sepsis. It is the most frequent Gram-negative bacterial pathogen recovered from cultures of blood from both community-acquired and nosocomial cases. We set out to determine the relationships between E. coli virulence factors (VFs), phylogenetic groups, and antibiotic resistance and whether bacteremia cases had a community, health care-associated. or nosocomial origin. Isolates from consecutive episodes of E. coli bacteremia in 303 patients presenting to a university hospital were screened for their VFs, phylogenetic group, and antibiotic resistance. The majority of VFs present in the collection were equally distributed between antibiotic-susceptible and multiple-drug-resistant (MDR) isolates, but the overall VF score was higher for isolates of community and health care-associated origin than those of nosocomial origin (P = 0.0002 and P = 0.0172, respectively); the papA, papG allele II, hlyA, and hek VFs were more prevalent in this cohort. Most isolates belonged to phylogenetic group B2, which harbored a greater proportion of antibiotic-susceptible isolates than MDR isolates (P = 0.04). The community, health care-associated, or nosocomial origin of E. coli bacteremia determines the virulence capacity of an isolate better than the phylogenetic group does. This study provides new insights into the relationships between the pathogenesis and epidemiology of E. coli bacteremia.
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Prevalence and associations of tcpC, a gene encoding a Toll/interleukin-1 receptor domain-containing protein, among Escherichia coli urinary tract infection, skin and soft tissue infection, and commensal isolates. J Clin Microbiol 2009; 48:966-8. [PMID: 20042631 DOI: 10.1128/jcm.01227-09] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
TcpC, a new Toll/interleukin-1 receptor domain-containing protein of uropathogenic Escherichia coli involved in the suppression of innate immunity, was found in 2008. The aim of the present study was to determine the prevalence of tcpC and its association with virulence factors and phylogenetic groups among strains from a collection of 212 E. coli isolates from urinary tract and skin and soft tissue infections and 90 commensal E. coli strains.
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Wellens A, Garofalo C, Nguyen H, Van Gerven N, Slättegård R, Hernalsteens JP, Wyns L, Oscarson S, De Greve H, Hultgren S, Bouckaert J. Intervening with urinary tract infections using anti-adhesives based on the crystal structure of the FimH-oligomannose-3 complex. PLoS One 2008; 3:e2040. [PMID: 18446213 PMCID: PMC2323111 DOI: 10.1371/journal.pone.0002040] [Citation(s) in RCA: 163] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2008] [Accepted: 03/17/2008] [Indexed: 11/19/2022] Open
Abstract
Background Escherichia coli strains adhere to the normally sterile human uroepithelium using type 1 pili, that are long, hairy surface organelles exposing a mannose-binding FimH adhesin at the tip. A small percentage of adhered bacteria can successfully invade bladder cells, presumably via pathways mediated by the high-mannosylated uroplakin-Ia and α3β1 integrins found throughout the uroepithelium. Invaded bacteria replicate and mature into dense, biofilm-like inclusions in preparation of fluxing and of infection of neighbouring cells, being the major cause of the troublesome recurrent urinary tract infections. Methodology/Principal Findings We demonstrate that α-d-mannose based inhibitors of FimH not only block bacterial adhesion on uroepithelial cells but also antagonize invasion and biofilm formation. Heptyl α-d-mannose prevents binding of type 1-piliated E. coli to the human bladder cell line 5637 and reduces both adhesion and invasion of the UTI89 cystitis isolate instilled in mouse bladder via catheterization. Heptyl α-d-mannose also specifically inhibited biofilm formation at micromolar concentrations. The structural basis of the great inhibitory potential of alkyl and aryl α-d-mannosides was elucidated in the crystal structure of the FimH receptor-binding domain in complex with oligomannose-3. FimH interacts with Manα1,3Manβ1,4GlcNAcβ1,4GlcNAc in an extended binding site. The interactions along the α1,3 glycosidic bond and the first β1,4 linkage to the chitobiose unit are conserved with those of FimH with butyl α-d-mannose. The strong stacking of the central mannose with the aromatic ring of Tyr48 is congruent with the high affinity found for synthetic inhibitors in which this mannose is substituted for by an aromatic group. Conclusions/Significance The potential of ligand-based design of antagonists of urinary tract infections is ruled by the structural mimicry of natural epitopes and extends into blocking of bacterial invasion, intracellular growth and capacity to fluxing and of recurrence of the infection.
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Affiliation(s)
- Adinda Wellens
- Department of Molecular and Cellular Interactions, Vrije Universiteit Brussel, Brussels, Belgium
- Ultrastructure, Vrije Universiteit Brussel, Brussels, Belgium
| | - Corinne Garofalo
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Hien Nguyen
- Department of Molecular and Cellular Interactions, Vrije Universiteit Brussel, Brussels, Belgium
- Ultrastructure, Vrije Universiteit Brussel, Brussels, Belgium
| | - Nani Van Gerven
- Viral Genetics, Vrije Universiteit Brussel, Brussels, Belgium
| | - Rikard Slättegård
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
| | | | - Lode Wyns
- Department of Molecular and Cellular Interactions, Vrije Universiteit Brussel, Brussels, Belgium
- Ultrastructure, Vrije Universiteit Brussel, Brussels, Belgium
| | - Stefan Oscarson
- Centre for Synthesis and Chemical Biology, University College Dublin, Belfield, Dublin, Ireland
| | - Henri De Greve
- Department of Molecular and Cellular Interactions, Vrije Universiteit Brussel, Brussels, Belgium
- Ultrastructure, Vrije Universiteit Brussel, Brussels, Belgium
| | - Scott Hultgren
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Julie Bouckaert
- Department of Molecular and Cellular Interactions, Vrije Universiteit Brussel, Brussels, Belgium
- Ultrastructure, Vrije Universiteit Brussel, Brussels, Belgium
- * E-mail:
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Starcic Erjavec M, Rijavec M, Krizan-Hergouth V, Fruth A, Zgur-Bertok D. Chloramphenicol- and tetracycline-resistant uropathogenic Escherichia coli (UPEC) exhibit reduced virulence potential. Int J Antimicrob Agents 2007; 30:436-42. [PMID: 17719751 DOI: 10.1016/j.ijantimicag.2007.06.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 06/22/2007] [Accepted: 06/26/2007] [Indexed: 10/22/2022]
Abstract
It is well documented that uropathogenic Escherichia coli (UPEC) isolates resistant to nalidixic acid have reduced virulence potential. Our goal was to assess whether UPEC isolates resistant to chloramphenicol, tetracycline and streptomycin also exhibit reduced virulence potential. Among 110 human UPEC isolates, the prevalences of the virulence factors fimH, papC, papGII, papGIII, sfa/focDE, afa, hlyA, cnf1, usp, ibeA, fyuA, iroN, iucD, ireA, and K1 and K5 capsules as well as of pathotypes, phylogenetic groups, O antigens and a pathogenicity island (PAI) marker were compared between chloramphenicol-, tetracycline-, streptomycin- and, as a control, nalidixic acid-resistant and -susceptible strains. Our findings show that among human UPEC isolates, not only nalidixic acid-resistant but also chloramphenicol- and tetracycline-resistant isolates have reduced virulence potential compared with susceptible strains. To our knowledge, this is the first report of a statistically significant reduction in virulence traits among chloramphenicol- and tetracycline-resistant isolates.
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Affiliation(s)
- Marjanca Starcic Erjavec
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Vecna pot 111, 1000 Ljubljana, Slovenia
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Rijavec M, Budic M, Mrak P, Müller-Premru M, Podlesek Z, Zgur-Bertok D. Prevalence of ColE1-like plasmids and colicin K production among uropathogenic Escherichia coli strains and quantification of inhibitory activity of colicin K. Appl Environ Microbiol 2006; 73:1029-32. [PMID: 17122402 PMCID: PMC1800769 DOI: 10.1128/aem.01780-06] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Colicin K exhibited pronounced inhibitory activity against uropathogenic Escherichia coli (UPEC) strains. Low prevalence of colicin K production and a relatively high prevalence of ColE1-like plasmids were determined among 215 UPEC strains from Slovenia. Sequencing of the colicin K-encoding pColK-K235 revealed a mosaic structure and the presence of the insertion sequence IS2.
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Affiliation(s)
- Matija Rijavec
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Vecna pot 111, Ljubljana, Slovenia
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