scholarly journals Balanced Input from the tRNA Prenyltransferase MiaA Controls the Stress Resistance and Virulence Potential of Extraintestinal Pathogenic Escherichia coli

2021 ◽  
Author(s):  
Matthew G. Blango ◽  
Brittany A. Fleming ◽  
William M. Kincannon ◽  
Alex Tran ◽  
Adam J. Lewis ◽  
...  

ABSTRACTAn ability to adapt to rapidly changing and often hostile environments is key to the success of many bacterial pathogens. In Escherichia coli, the highly conserved enzymes MiaA and MiaB mediate the sequential prenylation and methylthiolation of adenosine-37 within tRNAs that decode UNN codons. Here, we show that MiaA, but not MiaB, is critical to the fitness and virulence of extraintestinal pathogenic E. coli (ExPEC), a major cause of urinary tract and bloodstream infections. Deletion of miaA has pleiotropic effects, rendering ExPEC especially sensitive to stressors like nitrogen and oxygen radicals and osmotic shock. We find that stress can stimulate striking changes in miaA expression, which in turn can increase translational frameshifting and markedly alter the bacterial proteome. Cumulatively, these data indicate that ExPEC, and likely other organisms, can vary MiaA levels as a means to fine-tune translation and the spectrum of expressed proteins in response to changing environmental challenges.

2020 ◽  
Vol 19 (2) ◽  
pp. 447-453
Author(s):  
Abdulaziz Alqasim

Extra-intestinal pathogenic Escherichia coli (ExPEC) is commonly associated with causing urinary tract and bloodstream infections. Over the past two decades, the antimicrobial resistance of ExPEC has increasingly been reported [1]. Given that Saudi Arabia annually hosts mass religious events, such as Hajj, this review investigated several aspects of antimicrobial resistance of ExPEC in this country including the current prevalence of resistance and molecular epidemiology of ExPEC isolates. Generally, the overall prevalence of antibiotic resistance of ExPEC in Saudi Arabia is on increase. The current emergence of colistin resistance in ExPEC represents a major challenge to public health. Local molecular epidemiological studies have shown the dominance of E. coli sequence type 131 (E. coli ST131) over other major ExPEC STs. This is an important observation given that this clone has been associated with high multidrug resistance and extended-spectrum β-lactamases carriage. To reduce the burden of this resistance in the future, it would be crucial to avoid uncontrolled use of antibiotics in either clinical settings or animal food industry. Keywords: Extra-intestinal pathogenic Escherichia coli, Antimicrobial resistance, ST131, Saudi Arabia, Colistin resistance, Extended-spectrum β-lactamases


Antibiotics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 351
Author(s):  
Elisa Massella ◽  
Federica Giacometti ◽  
Paolo Bonilauri ◽  
Cameron J. Reid ◽  
Steven P. Djordjevic ◽  
...  

We recently described the genetic antimicrobial resistance and virulence profile of a collection of 279 commensal E. coli of food-producing animal (FPA), pet, wildlife and human origin. Phenotypic antimicrobial resistance (AMR) and the role of commensal E. coli as reservoir of extra-intestinal pathogenic Escherichia coli (ExPEC) virulence-associated genes (VAGs) or as potential ExPEC pathogens were evaluated. The most common phenotypic resistance was to tetracycline (76/279, 27.24%), sulfamethoxazole/trimethoprim (73/279, 26.16%), streptomycin and sulfisoxazole (71/279, 25.45% both) among the overall collection. Poultry and rabbit were the sources mostly associated to AMR, with a significant resistance rate (p > 0.01) to quinolones, streptomycin, sulphonamides, tetracycline and, only for poultry, to ampicillin and chloramphenicol. Finally, rabbit was the source mostly associated to colistin resistance. Different pandemic (ST69/69*, ST95, ST131) and emerging (ST10/ST10*, ST23, ST58, ST117, ST405, ST648) ExPEC sequence types (STs) were identified among the collection, especially in poultry source. Both ST groups carried high number of ExPEC VAGs (pandemic ExPEC STs, mean = 8.92; emerging ExPEC STs, mean = 6.43) and showed phenotypic resistance to different antimicrobials (pandemic ExPEC STs, mean = 2.23; emerging ExPEC STs, mean = 2.43), suggesting their role as potential ExPEC pathogens. Variable phenotypic resistance and ExPEC VAG distribution was also observed in uncommon ExPEC lineages, suggesting commensal flora as a potential reservoir of virulence (mean = 3.80) and antimicrobial resistance (mean = 1.69) determinants.


2020 ◽  
Vol 21 (8) ◽  
pp. 772-776
Author(s):  
Xiao-Pei Peng ◽  
Wei Ding ◽  
Jian-Min Ma ◽  
Jie Zhang ◽  
Jian Sun ◽  
...  

Dietary proteins are linked to the pathogenic Escherichia coli (E. coli) through the intestinal tract, which is the site where both dietary proteins are metabolized and pathogenic E. coli strains play a pathogenic role. Dietary proteins are degraded by enzymes in the intestine lumen and their metabolites are transferred into enterocytes to be further metabolized. Seven diarrheagenic E. coli pathotypes have been identified, and they damage the intestinal epithelium through physical injury and effector proteins, which lead to inhibit the digestibility and absorption of dietary proteins in the intestine tract. But the increased tryptophan (Trp) content in the feed, low-protein diet or milk fractions supplementation is effective in preventing and controlling infections by pathogenic E. coli in the intestine.


Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 467
Author(s):  
Dipak Kathayat ◽  
Dhanashree Lokesh ◽  
Sochina Ranjit ◽  
Gireesh Rajashekara

Avian pathogenic Escherichia coli (APEC) causes colibacillosis in avian species, and recent reports have suggested APEC as a potential foodborne zoonotic pathogen. Herein, we discuss the virulence and pathogenesis factors of APEC, review the zoonotic potential, provide the current status of antibiotic resistance and progress in vaccine development, and summarize the alternative control measures being investigated. In addition to the known virulence factors, several other factors including quorum sensing system, secretion systems, two-component systems, transcriptional regulators, and genes associated with metabolism also contribute to APEC pathogenesis. The clear understanding of these factors will help in developing new effective treatments. The APEC isolates (particularly belonging to ST95 and ST131 or O1, O2, and O18) have genetic similarities and commonalities in virulence genes with human uropathogenic E. coli (UPEC) and neonatal meningitis E. coli (NMEC) and abilities to cause urinary tract infections and meningitis in humans. Therefore, the zoonotic potential of APEC cannot be undervalued. APEC resistance to almost all classes of antibiotics, including carbapenems, has been already reported. There is a need for an effective APEC vaccine that can provide protection against diverse APEC serotypes. Alternative therapies, especially the virulence inhibitors, can provide a novel solution with less likelihood of developing resistance.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Pouya Reshadi ◽  
Fatemeh Heydari ◽  
Reza Ghanbarpour ◽  
Mahboube Bagheri ◽  
Maziar Jajarmi ◽  
...  

Abstract Background Transmission of antimicrobial resistant and virulent Escherichia coli (E. coli) from animal to human has been considered as a public health concern. This study aimed to determine the phylogenetic background and prevalence of diarrheagenic E. coli and antimicrobial resistance in healthy riding-horses in Iran. In this research, the genes related to six main pathotypes of E. coli were screened. Also, genotypic and phenotypic antimicrobial resistance against commonly used antibiotics were studied, then phylo-grouping was performed on all the isolates. Results Out of 65 analyzed isolates, 29.23 % (n = 19) were determined as STEC and 6.15 % (n = 4) as potential EPEC. The most prevalent antimicrobial resistance phenotypes were against amoxicillin/clavulanic acid (46.2 %) and ceftriaxone (38.5 %). blaTEM was the most detected resistance gene (98.4 %) among the isolates and 26.15 % of the E. coli isolates were determined as multi-drug resistant (MDR). Three phylo-types including B1 (76.92 %), A (13.85 %) and D (3.08 %) were detected among the isolates. Conclusions Due to the close interaction of horses and humans, these findings would place emphasis on the pathogenic and zoonotic potential of the equine strains and may help to design antimicrobial resistance stewardship programs to control the dissemination of virulent and multi-drug resistant E. coli strains in the community.


2011 ◽  
Vol 77 (14) ◽  
pp. 4949-4958 ◽  
Author(s):  
C. Sekse ◽  
M. Sunde ◽  
B.-A. Lindstedt ◽  
P. Hopp ◽  
T. Bruheim ◽  
...  

ABSTRACTA national survey ofEscherichia coliO26 in Norwegian sheep flocks was conducted, using fecal samples to determine the prevalence. In total, 491 flocks were tested, andE. coliO26 was detected in 17.9% of the flocks. One hundred forty-twoE. coliO26 isolates were examined for flagellar antigens (H typing) and four virulence genes, includingstxandeae, to identify possible Shiga toxin-producingE. coli(STEC) and enteropathogenicE. coli(EPEC). Most isolates (129 out of 142) were identified asE. coliO26:H11. They possessedeaeand may have potential as human pathogens, although only a small fraction were identified as STEC O26:H11, giving a prevalence in sheep flocks of only 0.8%. Correspondingly, the sheep flock prevalence of atypical EPEC (aEPEC) O26:H11 was surprisingly high (15.9%). The genetic relationship between theE. coliO26:H11 isolates was investigated by pulsed-field gel electrophoresis (PFGE) and multilocus variable number tandem repeat analysis (MLVA), identifying 63 distinct PFGE profiles and 22 MLVA profiles. Although the MLVA protocol was less discriminatory than PFGE and a few cases of disagreement were observed, comparison by partition mapping showed an overall good accordance between the two methods. A close relationship between a few isolates of aEPEC O26:H11 and STEC O26:H11 was identified, but all theE. coliO26:H11 isolates should be considered potentially pathogenic to humans. The present study consisted of a representative sampling of sheep flocks from all parts of Norway. This is the first large survey of sheep flocks focusing onE. coliO26 in general, including results of STEC, aEPEC, and nonpathogenic isolates.


Author(s):  
Braden Wiser ◽  
S.E. Niebuhr ◽  
James Dickson

A mixed culture of different isolates of Salmonella serovar I 4,[5], 12:i:- was compared to a mixed culture of reference Salmonella serovars as well as non-pathogenic Escherichia coli surrogates.. The two groups of Salmonella were compared for their resistance to commonly used pork carcass interventions, survival in ground pork and thermal resistance in ground pork. There were no observed differences between the response of the two different groups of Salmonella serovars and the non-pathogenic E. coli surrogates within intervention type.  There were no observed differences in the recovery and survival of the two different groups of Salmonella serovars in pork which had been treated with interventions, ground and stored at 5 o C for two weeks. Finally, there were no observed differences in heat resistance between the two different groups of Salmonella serovars in ground pork which had been treated with interventions, ground and stored at 5 o C for two weeks. However, there were observed differences in heat resistance in both groups of Salmonella serovars associated with refrigerated storage. The heat resistance of both groups of Salmonella serovars decreased after refrigerated storage. The results of these experiments demonstrate that there were no observed differences between the responses of Salmonella serovar I 4,[5], 12:i:- when compared to the reference Salmonella serovars to commonly used interventions in the pork industry, and therefore do not present a unique challenge to the pork industry.


Vestnik ◽  
2021 ◽  
pp. 68-74
Author(s):  
М.Е. Рамазанов ◽  
В.Н. Сон ◽  
М.Р. Рысулы ◽  
С.Т. Турсуналиев ◽  
Е.Б. Еспенбетов

Представлены результаты проспективного обследования 80 больных ГКБ №7 с бактериемией с октября 2019 года по февраль 2021 года из различных отделений госпиталя. Производилась оценки показателей маркеров сепсиса - пресепсина, прокальцитонина и С-реактивного белка (СРБ) в крови больных в динамике эмпирической терапии антимикробными препаратами (АМП). Наибольшее число больных с выявленной бактериемией находилось в отделении ОАРИТ - 39 пациентов, у 25 из них был диагностирован сепсис по шкале СЕПСИС III, вызванный известными патогенами Staphylococcus aureus (46,6%) и Escherichia coli (36,6%). Для эмпирического лечения применялись различные антибиотики: ампенициллин, амикацин, меропенем, цефотаксим, метрид, ципрофлоксацин, ципрокс, цефлокс, цефазолин, цефтриаксон, левофлоксацин. Уровни прокальцитонина составляют для больных с клиническими изолятами E. coli 20,8±3,1нг/мл, а для изолятов St. aureus 15,7±1,8 нг/мл. После терапии АМП наблюдается значительное снижение показателей до 1,43±0,6 и 2,3±0,9 нг/мл., что позволяет признать эффективность эмпирической антибиотикотерапии при инфекциях кровотока. Высокая чувствительность клинических изолятов Escherichia coli отмечена к препаратам группы карбапенемов - имипенему и меропенему (90,9%), низкая к эртапенему (72,7%). 100% чувствительность все изоляты показали по отношению к АМП из группы глицилциклинов - тигециклину, который структурно сходен с тетрациклинами. Высокой резистеностью клинические изоляты Staphylococcus aureus обладают к пенициллину (92,9%), липопептиду природного происхождения даптомицину (85,8%) и препарату из группы линкозамидов - клиндамицину (64,3%). The results of a prospective examination of 80 patients with bacteremia from October 2019 to February 2021 from various departments of the hospital are presented. The largest number of patients with detected bacteremia were in the OARIT department - 39 patients, 25 of them were diagnosed with sepsis according to the SEPSIS III scale, caused by known pathogens Staphylococcus aureus (46.6%) and Escherichia coli (36.6%). For empirical treatment, various antibiotics were used: ampenicillin, amikacin, meropenem, cefotaxime, metrid, ciprofloxacin, ciprox, ceflox, cefazolin, ceftriaxone, levofloxacin. Procalcitonin levels for patients with clinical E. coli isolates are 20.8 ± 3.1 ng / ml, and for St. aureus 15.7 ± 1.8 ng / ml. After AMP therapy, there is a significant decrease in indicators to 1.43 ± 0.6 and 2.3 ± 0.9 ng / ml, which makes it possible to recognize the effectiveness of empiric antibiotic therapy for bloodstream infections. High sensitivity of clinical isolates of Escherichia coli was noted to drugs of the carbapenem group - imipenem and meropenem (90.9%), low to ertapenem (72.7%). All isolates showed 100% sensitivity to AMPs from the glycylcycline group - tigecycline, which is structurally similar to tetracyclines. Clinical isolates of Staphylococcus aureus are highly resistant to penicillin (92.9%), natural lipopeptide daptomycin (85.8%), and a drug from the lincosamide group - clindamycin (64.3%).


2001 ◽  
Vol 69 (2) ◽  
pp. 937-948 ◽  
Author(s):  
Lila Lalioui ◽  
Chantal Le Bouguénec

ABSTRACT We recently described a new afimbrial adhesin, AfaE-VIII, produced by animal strains associated with diarrhea and septicemia and by human isolates associated with extraintestinal infections. Here, we report that the afa-8 operon, encoding AfaE-VIII adhesin, from the human blood isolate Escherichia coli AL862 is carried by a 61-kb genomic region with characteristics typical of a pathogenicity island (PAI), including a size larger than 10 kb, the presence of an integrase-encoding gene, the insertion into a tRNA locus (pheR), and the presence of a small direct repeat at each extremity. Moreover, the G+C content of the afa-8 operon (46.4%) is lower than that of the E. coli K-12/MG1655 chromosome (50.8%). Within this PAI, designated PAI IAL862, we identified open reading frames able to code for products similar to proteins involved in sugar utilization. Four probes spanning these sequences hybridized with 74.3% of pathogenicafa-8-positive E. coli strains isolated from humans and animals, 25% of human pathogenic afa-8-negativeE. coli strains, and only 8% of fecal strains (P = 0.05), indicating that these sequences are strongly associated with the afa-8 operon and that this genetic association may define a PAI widely distributed among human and animal afa-8-positive strains. One of the distinctive features of this study is that E. coli AL862 also carries another afa-8-containing PAI (PAI IIAL862), which appeared to be similar in size and genetic organization to PAI IAL862 and was inserted into the pheV gene. We investigated the insertion sites of afa-8-containing PAI in human and bovine pathogenic E. coli strains and found that this PAI preferentially inserted into the pheV gene.


Pathogens ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 811
Author(s):  
Md. Akil Hossain ◽  
Hae-Chul Park ◽  
Sung-Won Park ◽  
Seung-Chun Park ◽  
Min-Goo Seo ◽  
...  

Pathogenic Escherichia coli (E. coli)-associated infections are becoming difficult to treat because of the rapid emergence of antibiotic-resistant strains. Novel approaches are required to prevent the progression of resistance and to extend the lifespan of existing antibiotics. This study was designed to improve the effectiveness of traditional antibiotics against E. coli using a combination of the gallic acid (GA), hamamelitannin, epicatechin gallate, epigallocatechin, and epicatechin. The fractional inhibitory concentration index (FICI) of each of the phenolic compound-antibiotic combinations against E. coli was ascertained. Considering the clinical significance and FICI, two combinations (hamamelitannin-erythromycin and GA-ampicillin) were evaluated for their impact on certain virulence factors of E. coli. Finally, the effects of hamamelitannin and GA on Rattus norvegicus (IEC-6) cell viability were investigated. The FICIs of the antibacterial combinations against E. coli were 0.281–1.008. The GA-ampicillin and hamamelitannin-erythromycin combinations more effectively prohibited the growth, biofilm viability, and swim and swarm motilities of E. coli than individual antibiotics. The concentration of hamamelitannin and GA required to reduce viability by 50% (IC50) in IEC-6 cells was 988.54 μM and 564.55 μM, correspondingly. GA-ampicillin and hamamelitannin-erythromycin may be potent combinations and promising candidates for eradicating pathogenic E. coli in humans and animals.


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