scholarly journals Spectrum of Diarrheagenic Escherichia coli in Drinking and Wastewater in Rafha City of Saudi Arabia

2021 ◽  
pp. 327-334
Author(s):  
Akbar Ali ◽  
Samreen Soomro ◽  
Muhammad Shahid Nadeem ◽  
Elsamoul Ibrahim Ahmedani
Keyword(s):  
Saudi Arabia ◽  
Target Genes ◽  
Genetic Difference ◽  
Geographical Location ◽  
Etiologic Agent ◽  
Virulence Determinants ◽  
E Coli ◽  
Detection And Identification ◽  
Wastewater Samples ◽  
Different Strains

Introduction: E coli is one of the most important etiologic agent of diarrhea in children and adults. Based on the clinical features and virulence determinants, there are five major E. coli strains which cause diarrhea; Enterohemorrhagic E. coli (EHEC), Enteropathogenic E. coli (EPEC), Enterotoxigenic E. coli (ETEC), Enteroinvasive E. coli (EIEC) and Enteroaggregative E. coli (EAEC). The PCR based identification proves to be a better choice as it can differentiate between different strains on the basis of genetic difference. Aim: The purpose of the current study was to isolate diarrheagenic E. coli from the drinking and wastewater from Rafha city of Saudi Arabia. Methodology: One 100 drinking and wastewater samples (50 each) were included in the study. The samples were cultured on MacConkey agar plates at 37 oC for 24 hours. Pink colonies were carefully picked and subjected to DNA isolation and PCR detection and identification of E. coli and Diarrheagenic E. coli. The detected PCR products were sequenced for the confirmation. Results: We identified 5 isolates out of 50 wastewater samples (10%) which were further categorized into 3 different DEC pathotypes. They included ETEC (2 out of 5), atypical EPEC (1 out of 5), and EAEC (1 out of 5); EIEC and EHEC were not detected. Discussion and Conclusion: The prevalence of DEC strains is different across different studies which depends on different factors such as geographical location, number of samples taken, and the number and type of the target genes selected. The prevalence of DEC in the current study was much lower than other reported studies.  Although the percentage of DEC strains in the wastewater samples from WWTP of Rafha was moderate to low, it can be a considerable risk factor for the people using ground water for drinking.

scholarly journals Reconstruction of Fur pan-regulon uncovers the complexity and diversity of transcriptional regulation in E. coli

2020 ◽  
Author(s):  
Ye Gao ◽  
Ina Bang ◽  
Yara Seif ◽  
Gayoung Nam ◽  
Anand V. Sastry ◽  
...  
Keyword(s):  
Binding Sites ◽  
Iron Homeostasis ◽  
Target Genes ◽  
Wall Structure ◽  
Ferric Uptake Regulator ◽  
Complete Understanding ◽  
E Coli ◽  
Wide Range ◽  
Different Strains ◽  
Comprehensive Study

AbstractRegulons for many transcription factors have been elucidated in model strains leading to an understanding of their role in producing physiological states. Comparative analysis of a regulon and its target genes between different strains of the same species is lacking. Ferric uptake regulator (Fur), involved in iron homeostasis, is one of the most conserved TFs, and is present in a wide range of bacteria. Using ChIP-exo experiments, we performed a comprehensive study of Fur binding sites in nine Escherichia coli strains with different lifestyles. 79 of the 431 target genes (18%) found belong to Fur core regulon, comprising genes involved in ion transport and metabolism, energy production and conversion, and amino acid metabolism and transport. 179 of the target genes (42%) comprise the accessory regulon, most of which were related to cell wall structure and biogenesis, and virulence factor pathways. The remaining target genes (173 or 40%) were in the unique regulon, with gene functions that were largely unknown. Furthermore, deletion of the fur gene led to distinct phenotypes in growth, motility, antibiotic resistance, and the change of siderophore production. These results provide a more complete understanding of how Fur regulates a set of target genes with surprising variation in closely related bacteria.

A Simple PCR-Based Macroarray System for Detection of Multiple Gene Markers in the Identification of Priority Enterohemorrhagic Escherichia coli

2011 ◽  
Vol 74 (3) ◽  
pp. 365-372 ◽  
Author(s):  
BURTON W. BLAIS ◽  
AMALIA MARTINEZ-PEREZ
Keyword(s):  
Escherichia Coli ◽  
Target Genes ◽  
Enrichment Culture ◽  
Enterohemorrhagic Escherichia Coli ◽  
High Rate ◽  
Antigenic Determinants ◽  
Bacterial Strains ◽  
Gene Markers ◽  
E Coli ◽  
Different Strains

Enterohemorrhagic Escherichia coli (EHEC) strains bearing the O antigenic determinants O157, O26, O111, O103, and O145 have a high rate of association with foodborne illness worldwide. To expand Canadian food inspection capability, a cloth-based hybridization array system (CHAS) was developed for the identification and characterization of priority EHEC. This method targets key virulence genes (eae, hlyA, vt1, and vt2) plus the rfbE gene specifying the O157 antigenic determinant, and the wzx genes specifying the O26, O111, O103, and O145 determinants. Multiplex PCR products incorporating a digoxigenin label were detected by hybridization with an array of specific oligonucleotide probes immobilized on a polyester cloth support, with subsequent immunoenzymatic assay of the captured amplicons. This method identified the relevant markers in 85 different strains bearing various combinations of the target genes (virulence and priority O-antigen markers). None of the target genes was detected in 26 different strains of other E. coli and non–E. coli bacteria. The CHAS demonstrated 100% inclusivity and 100% exclusivity characteristics, with respect to detection of the various markers among different bacterial strains. The CHAS demonstrated 100% inclusivity and 100% exclusivity characteristics, with respect to detection of the markers among various target and nontarget bacteria. The entire procedure could be completed in less than 5 h, and is useful for the identification of priority EHEC colonies isolated from foods by using enrichment culture techniques.

scholarly journals Distribution of Pathogenicity Islands Among Uropathogenic Escherichia coli Isolates From Patients With Urinary Tract Infections

2020 ◽  
Vol 8 (2) ◽  
pp. 39-43
Author(s):  
Ehsan Asadi ◽  
Mohammad Mohammadzadeh ◽  
Mohammad Niakan
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Etiologic Agent ◽  
Uropathogenic Escherichia Coli ◽  
Pathogenicity Islands ◽  
Virulence Determinants ◽  
E Coli ◽  
Virulence Markers ◽  
Microbiological Methods ◽  
Tract Infections

Background: Uropathogenic Escherichia coli (UPEC) is one of the most common etiologic agent of urinary tract infection (UTI). The ability of Escherichia coli to cause UTI is associated with specific virulence determinants, which are encoded by pathogenicity islands (PAIs). Objectives: This study aimed to investigate the distribution of PAIs among the UPEC isolates collected from patients with UTIs. Materials and Methods: In this study, a total of 100 E. coli isolates were collected from patients with UTIs using standard microbiological methods. Polymerase chain reaction (PCR) was used for the identification of the main PAIs of UPEC according to insertion sites and virulence markers. Results: In total, PAI IV536, PAI III536, PAI I536, PAI, IICFT073, PAI ICFT073, PAI IIJ96, PAI II536, and PAI IJ96 were detected in 23, 22, 17, 17, 13, 11, 11, and 8% of isolates. PAI combinations were identified in 15% of isolates. Conclusion: The results showed that PAIs of UPEC are not strain-specific and some strains can carry the PAIs associated with the prototype strains of UPEC simultaneously.

Transport of escherichia coli through soil to groundwater traced by randomly amplified polymorphic DNA (RAPD)

1997 ◽  
Vol 35 (11-12) ◽  
pp. 351-357 ◽  
Author(s):  
R. Rothmaier ◽  
A. Weidenmann ◽  
K. Botzenhart
Keyword(s):  
Negative Impact ◽  
Random Amplified Polymorphic Dna ◽  
Coli Strain ◽  
Soil Samples ◽  
Test Field ◽  
Liquid Manure ◽  
E Coli ◽  
Rapd Pattern ◽  
Geological Situation ◽  
Different Strains

Isolates (50) of E. coli obtained from liquid manure (20 bovine, 20 porcine) were genotyped using random amplified polymorphic DNA (RAPD). Typing revealed 9 and 14 different strains in bovine and porcine liquid manure respectively with no strains in common. One porcine strain, showing a simple RAPD pattern, was subcultured and spread on a test field (1.5l/m2 at 1010 cfu/l) in a drinking water protection zone with loamy to sandy sediments in the Donauried area, Baden-Wurttemberg. Soil samples and groundwaters were collected at monthly intervals October 1994 – June 1995 during which 114 E. coli isolates were recovered. The first occurrence and maximum concentration of E. coli in soil samples taken from more than 20cm depth was in January 1995, declining rapidly with depth and time. All isolates from soil and only one from groundwater showed the RAPD pattern of the spread E. coli strain. The results could not demonstrate a severe negative impact of the spreading of liquid manure on the bacteriological quality of the groundwater in the given geological situation. The distinct strain patterns found in different kinds of liquid manure suggest that genotyping of E. coli by RAPD may be an adequate tool for tracing sources of faecal contamination.

scholarly journals Continuous Real-Time Motility Analysis of Acanthamoeba Reveals Sustained Movement in Absence of Nutrients

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 995
Author(s):  
Allison Campolo ◽  
Valerie Harris ◽  
Rhonda Walters ◽  
Elise Miller ◽  
Brian Patterson ◽  
...  
Keyword(s):  
Contact Lens ◽  
Contact Lenses ◽  
Axenic Culture ◽  
Acanthamoeba Keratitis ◽  
Ocular Infection ◽  
Glass Coverslip ◽  
E Coli ◽  
Total Distance ◽  
Care Systems ◽  
Different Strains

Acanthamoeba keratitis is a serious ocular infection which is challenging to treat and can lead to blindness. While this pathogen is ubiquitous and can contaminate contact lenses after contact with water, its habits remain elusive. Understanding this organism’s natural behavior will better inform us on how Acanthamoeba colonize contact lens care systems. Acanthamoeba trophozoites were allowed to adhere to either a glass coverslip or non-nutrient agar (NNA) within a flow cell with nutrients (Escherichia coli or an axenic culture medium (AC6)) or without nutrients (Ringer’s solution). Images were taken once every 24 s over 12 h and compiled, and videos were analyzed using ImageJ Trackmate software. Acanthamoeba maintained continuous movement for the entire 12 h period. ATCC 50370 had limited differences between conditions and surfaces throughout the experiment. Nutrient differences had a noticeable impact for ATCC 30461, where E. coli resulted in the highest total distance and speed during the early periods of the experiment but had the lowest total distance and speed by 12 h. The Ringer’s and AC6 conditions were the most similar between strains, while Acanthamoeba in the E. coli and NNA conditions demonstrated significant differences between strains (p < 0.05). These results indicate that quantifiable visual tracking of Acanthamoeba may be a novel and robust method for identifying the movement of Acanthamoeba in relation to contact lens care products. The present study indicates that Acanthamoeba can undertake sustained movement for at least 12 h with and without nutrients, on both rough and smooth surfaces, and that different strains have divergent behavior.

scholarly journals ESBL Activity, MDR, and Carbapenem Resistance among Predominant Enterobacterales Isolated in 2019

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 744
Author(s):  
Altaf Bandy ◽  
Bilal Tantry
Keyword(s):  
Escherichia Coli ◽  
Saudi Arabia ◽  
Antimicrobial Resistance ◽  
Carbapenem Resistance ◽  
Resistant Bacteria ◽  
Sociodemographic Characteristics ◽  
Chi Square ◽  
E Coli ◽  
Chi Square Test ◽  
Resistance Rates

Antimicrobial-resistance in Enterobacterales is a serious concern in Saudi Arabia. The present study retrospectively analyzed the antibiograms of Enterobacterales identified from 1 January 2019 to 31 December 2019 from a referral hospital in the Aljouf region of Saudi Arabia. The revised document of the Centers for Disease Control (CDC) CR-2015 and Magiorakos et al.’s document were used to define carbapenem resistance and classify resistant bacteria, respectively. The association of carbapenem resistance, MDR, and ESBL with various sociodemographic characteristics was assessed by the chi-square test and odds ratios. In total, 617 Enterobacterales were identified. The predominant (n = 533 (86.4%)) isolates consisted of 232 (37.6%), 200 (32.4%), and 101 (16.4%) Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis, respectively. In general, 432 (81.0%) and 128 (24.0%) isolates were of MDR and ESBL, respectively. The MDR strains were recovered in higher frequency from intensive care units (OR = 3.24 (1.78–5.91); p < 0.01). E. coli and K. pneumoniae resistance rates to imipenem (2.55 (1.21–5.37); p < 0.01) and meropenem (2.18 (1.01–4.67); p < 0.04), respectively, were significantly higher in winter. The data emphasize that MDR isolates among Enterobacterales are highly prevalent. The studied Enterobacterales exhibited seasonal variation in antimicrobial resistance rates towards carbapenems and ESBL activity.

Polyester Cloth–Based Hybridization Array System for Identification of Enterohemorrhagic Escherichia coli Serogroups O26, O45, O103, O111, O121, O145, and O157

2012 ◽  
Vol 75 (9) ◽  
pp. 1691-1697 ◽  
Author(s):  
BURTON W. BLAIS ◽  
MARTINE GAUTHIER ◽  
MYLÈNE DESCHÊNES ◽  
GEORGE HUSZCZYNSKI
Keyword(s):  
Escherichia Coli ◽  
Marker Gene ◽  
Enterohemorrhagic Escherichia Coli ◽  
Oligonucleotide Probes ◽  
E Coli ◽  
Polyester Cloth ◽  
Gene Profiles ◽  
Pcr Products ◽  
Different Strains ◽  
Immunoenzymatic Assay

A cloth-based hybridization array system (CHAS) was developed for the identification of foodborne colony isolates of seven priority enterohemorrhagic Escherichia coli (EHEC-7) serogroups targeted by U.S. food inspection programs. Gene sequences associated with intimin; Shiga-like toxins 1 and 2; and the antigenic markers O26, O45, O103, O111, O121, O145, and O157 were amplified in a multiplex PCR incorporating a digoxigenin label, and detected by hybridization of the PCR products with an array of specific oligonucleotide probes immobilized on a polyester cloth support, with subsequent immunoenzymatic assay of the captured amplicons. The EHEC-7 CHAS exhibited 100% inclusivity and 100% exclusivity characteristics with respect to detection of the various markers among 89 different E. coli strains, with various marker gene profiles and 15 different strains of non–E. coli bacteria.

Prevalence and distribution of different diarrhoeagenicEscherichia colivirulotypes in major water bodies in Bangladesh

2013 ◽  
Vol 141 (12) ◽  
pp. 2516-2525 ◽  
Author(s):  
S. AKTER ◽  
M. ISLAM ◽  
K. S. AFREEN ◽  
N. AZMUDA ◽  
S. I. KHAN ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Regional Distribution ◽  
Distribution Patterns ◽  
Aquatic Systems ◽  
Water Bodies ◽  
Virulence Determinants ◽  
Waterborne Pathogen ◽  
E Coli ◽  
Enriched Cultures ◽  
Natural Water Bodies

SUMMARYEscherichia coli, a prominent waterborne pathogen, causes a variety of gastrointestinal and extraintestinal infections that depend on virulence determinants. To monitor natural aquatic systems for virulence-associated genes ofE. coli, multiplex PCR was used in a survey covering 46 major natural water bodies in Bangladesh. DNA was extracted directly from water samples as well as from pre-enriched and enriched cultures during three successive seasons and assessed forE. colivirulotype distribution. From the five virulotypes, genes from the enterotoxigenic (ETEC), enteropathogenic (EPEC), and enterohaemorrhagic (EHEC) virulotypes were detected consistently, but genes from the enteroinvasive (EIEC) and enteroaggregative (EAEC) virulotypes were traced only occasionally. ETEC was the most prevalent virulotype, followed by EPEC. However, EIEC and EAEC virulotypes could not be detected in winter or the rainy season, respectively. Specific regional distribution patterns of differentE. colivirulotypes and their temporal fluctuations were identified. These observations may assist with assessing seasonal risk and identifying vulnerable areas of the country prone toE. coli-associated outbreaks.

scholarly journals Investigation of Biotransformation Products of p-Methoxymethylamphetamine and Dihydromephedrone in Wastewater by High-Resolution Mass Spectrometry

Metabolites ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 66
Author(s):  
Juliet Kinyua ◽  
Aikaterini K. Psoma ◽  
Nikolaos I. Rousis ◽  
Maria-Christina Nika ◽  
Adrian Covaci ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Wastewater Treatment Plants ◽  
High Resolution Mass Spectrometry ◽  
Transformation Products ◽  
New Psychoactive Substances ◽  
Batch Reactors ◽  
Flight Mass Spectrometry ◽  
Detection And Identification ◽  
Wastewater Samples ◽  
Set Up

There is a paucity of information on biotransformation and stability of new psychoactive substances (NPS) in wastewater. Moreover, the fate of NPS and their transformation products (TPs) in wastewater treatment plants is not well understood. In this study, batch reactors seeded with activated sludge were set up to evaluate biotic, abiotic, and sorption losses of p-methoxymethylamphetamine (PMMA) and dihydromephedrone (DHM) and identify TPs formed during these processes. Detection and identification of all compounds was performed with target and suspect screening approaches using liquid chromatography quadrupole-time-of-flight mass spectrometry. Influent and effluent 24 h composite wastewater samples were collected from Athens from 2014 to 2020. High elimination rates were found for PMMA (80%) and DHM (97%) after a seven-day experiment and degradation appeared to be related to biological activity in the active bioreactor. Ten TPs were identified and the main reactions were O- and N-demethylation, oxidation, and hydroxylation. Some TPs were reported for the first time and some were confirmed by reference standards. Identification of some TPs was enhanced by the use of an in-house retention time prediction model. Mephedrone and some of its previously reported human metabolites were formed from DHM incubation. Retrospective analysis showed that PMMA was the most frequently detected compound.

scholarly journals Phylogenetic Grouping and Virulence Potential of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Strains in Cattle

2012 ◽  
Vol 78 (13) ◽  
pp. 4677-4682 ◽  
Author(s):  
Charlotte Valat ◽  
Frédéric Auvray ◽  
Karine Forest ◽  
Véronique Métayer ◽  
Emilie Gay ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Determinants ◽  
Phylogenetic Groups ◽  
Content Type ◽  
E Coli ◽  
Extended Spectrum ◽  
Specific Distribution ◽  
Extended Spectrum Beta Lactamases ◽  
Phylogenetic Grouping ◽  
Almost All

ABSTRACTIn line with recent reports of extended-spectrum beta-lactamases (ESBLs) inEscherichia coliisolates of highly virulent serotypes, such as O104:H4, we investigated the distribution of phylogroups (A, B1, B2, D) and virulence factor (VF)-encoding genes in 204 ESBL-producingE. coliisolates from diarrheic cattle. ESBL genes, VFs, and phylogroups were identified by PCR and a commercial DNA array (Alere, France). ESBL genes belonged mostly to the CTX-M-1 (65.7%) and CTX-M-9 (27.0%) groups, whereas those of the CTX-M-2 and TEM groups were much less represented (3.9% and 3.4%, respectively). One ESBL isolate wasstx1andeaepositive and belonged to a major enterohemorrhagicE. coli(EHEC) serotype (O111:H8). Two other isolates wereeaepositive butstxnegative; one of these had serotype O26:H11. ESBL isolates belonged mainly to phylogroup A (55.4%) and, to lesser extents, to phylogroups D (25.5%) and B1 (15.6%), whereas B2 strains were quasi-absent (1/204). The number of VFs was significantly higher in phylogroup B1 than in phylogroups A (P= 0.04) and D (P= 0.02). Almost all of the VFs detected were found in CTX-M-1 isolates, whereas only 64.3% and 33.3% of them were found in CTX-M-9 and CTX-M-2 isolates, respectively. These results indicated that the widespread dissemination of theblaCTX-Mgenes within theE. colipopulation from cattle still spared the subpopulation of EHEC/Shiga-toxigenicE. coli(STEC) isolates. In contrast to other reports on non-ESBL-producing isolates from domestic animals, B1 was not the main phylogroup identified. However, B1 was found to be the most virulent phylogroup, suggesting host-specific distribution of virulence determinants among phylogenetic groups.

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