scholarly journals Extraintestinal Escherichia coli Carrying Virulence Genes in Coastal Marine Sediments

2010 ◽  
Vol 76 (17) ◽  
pp. 5659-5668 ◽  
Author(s):  
G. M. Luna ◽  
C. Vignaroli ◽  
C. Rinaldi ◽  
A. Pusceddu ◽  
L. Nicoletti ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Marine Sediments ◽  
Large Scale ◽  
Microbiological Quality ◽  
Genotypic Diversity ◽  
Coastal Sediments ◽  
Fecal Coliforms ◽  
Biochemical Tests ◽  
Term Survival ◽  
E Coli

ABSTRACT Despite the recognized potential of long-term survival or even growth of fecal indicators bacteria (FIB) in marine sediments, this compartment is largely ignored by health protection authorities. We conducted a large-scale study over approximately 50 km of the Marche coasts (Adriatic Sea) at depths ranging from 2 to 5 m. Total and fecal coliforms (FC) were counted by culture-based methods. Escherichia coli was also quantified using fluorescence in situ hybridization targeting specific 16S rRNA sequences, which yielded significantly higher abundances than culture-based methods, suggesting the potential importance of viable but nonculturable E. coli cells. Fecal coliforms displayed high abundances at most sites and showed a prevalence of E. coli. FC isolates (n = 113) were identified by API 20E, additional biochemical tests, and internal transcribed spacer-PCR. E. coli strains, representing 96% of isolates, were then characterized for genomic relatedness and phylogenetic group (A, B1, B2, and D) of origin by randomly amplified polymorphic DNA and multiplex-PCR. The results indicated that E. coli displayed a wide genotypic diversity, also among isolates from the same station, and that 44 of the 109 E. coli isolates belonged to groups B2 and D. Further characterization of B2 and D isolates for the presence of 11 virulence factor genes (pap, sfa/foc, afa, eaeA, ibeA, traT, hlyA, stx 1, stx 2, aer, and fyuA) showed that 90% of B2 and 65% of D isolates were positive for at least one of these. Most of the variance of both E. coli abundance and assemblage composition (>62%) was explained by a combination of physical-chemical and trophic variables. These findings indicate that coastal sediments could represent a potential reservoir for commensal and pathogenic E. coli and that E. coli distribution in marine coastal sediments largely depends upon the physical and trophic status of the sediment. We conclude that future sampling designs aimed at monitoring the microbiological quality of marine coastal areas should not further neglect the analysis of the sediment and that monitoring of these environments can be improved by including molecular methods as a complement of culture-based techniques.

scholarly journals Phenotypic and Genotypic Characterization of Escherichia coli Isolated from Untreated Surface Waters

2013 ◽  
Vol 7 (1) ◽  
pp. 9-19 ◽  
Author(s):  
Kristopher J Janezic ◽  
Blake Ferry ◽  
Eric W Hendricks ◽  
Brian A Janiga ◽  
Tiffany Johnson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Surface Waters ◽  
Antimicrobial Agents ◽  
Genotypic Variation ◽  
Virulence Gene ◽  
Genotypic Diversity ◽  
Housekeeping Gene ◽  
Polymyxin B ◽  
Fecal Coliforms ◽  
E Coli

A common member of the intestinal microbiota in humans and animals isEscherichia coli. Based on the presence of virulence factors,E. colican be potentially pathogenic. The focus of this study was to isolateE. colifrom untreated surface waters (37 sites) in Illinois and Missouri and determine phenotypic and genotypic diversity among isolates. Water samples positive for fecal coliforms based on the Colisure®test were streaked directly onto Eosin Methylene Blue (EMB) agar (37°C) or transferred to EC broth (44.5°C). EC broth cultures producing gas were then streaked onto EMB agar. Forty-five isolates were identified asE. coliusing API 20E and Enterotube II identification systems, and some phenotypic variation was observed in metabolism and fermentation. Antibiotic susceptibility of each isolate was also determined using the Kirby-Bauer Method. Differential responses to 10 antimicrobial agents were seen with 7, 16, 2, and 9 of the isolates resistant to ampicillin, cephalothin, tetracycline, and triple sulfonamide, respectively. All of the isolates were susceptible or intermediate to amoxicillin, ciprofloxacin, polymyxin B, gentamicin, imipenem, and nalidixic acid. Genotypic variation was assessed through multiplex Polymerase Chain Reaction for four virulence genes (stx1andstx2[shiga toxin],eaeA[intimin]; andhlyA[enterohemolysin]) and one housekeeping gene (uidA[β-D-glucuronidase]). Genotypic variation was observed with two of the isolates possessing the virulence gene (eaeA) for intimin. These findings increase our understanding of the diversity ofE. coliin the environment which will ultimately help in the assessment of this organism and its role in public health.

Comparison of culturable fecal coliforms and Escherichia coli enumeration in freshwaters

2007 ◽  
Vol 53 (6) ◽  
pp. 798-801 ◽  
Author(s):  
Tamara Garcia-Armisen ◽  
Josué Prats ◽  
Pierre Servais
Keyword(s):  
Escherichia Coli ◽  
Microbiological Quality ◽  
Fecal Coliforms ◽  
Quality Data ◽  
Plate Count ◽  
Most Probable Number ◽  
Tetrazolium Chloride ◽  
Probable Number ◽  
E Coli ◽  
Glucuronidase Activity

Fecal coliforms (FC) counts were compared with Escherichia coli counts in differently contaminated freshwater samples (n = 166). FC were enumerated by plate count on triphenyl 2,3,5-tetrazolium chloride Tergitol medium. Escherichia coli were enumerated by the most probable number microplate method based on the detection of glucuronidase activity. FC and E. coli counts were highly correlated; an average E. coli/FC ratio equal to 0.77 was found, meaning that on average, 77% of FC were E. coli. Knowing the E. coli/FC ratio allows us to convert the historical microbiological quality data expressed in FC counts into E. coli abundance and thus to compare with present and future monitoring data that are (or will be) based on E. coli enumeration.

Microbiological quality of bottled water sold in Canada

1986 ◽  
Vol 32 (11) ◽  
pp. 891-893 ◽  
Author(s):  
Donald W. Warburton ◽  
Pearl I. Peterkin ◽  
Karl F. Weiss ◽  
Murray A. Johnston
Keyword(s):  
Escherichia Coli ◽  
Mineral Water ◽  
Microbiological Quality ◽  
Bottled Water ◽  
Colony Count ◽  
Fecal Coliforms ◽  
Water Industry ◽  
E Coli

The microbiological quality of bottled water sold in Canada was evaluated. A total of 114 lots of bottled water, both domestic and imported, were analyzed for aerobic colony count, coliforms, fecal coliforms, and Escherichia coli. No fecal coliforms or E. coli were found. Nineteen (46%) of the 41 lots of domestic purified water were found to exceed aerobic colony count standards and another lot exceeded coliform standards. One lot each of domestic and imported mineral water exceeded coliform standards. If mineral water were governed by the aerobic colony count standards for bottled water, then five lots each of both domestic and imported mineral water would have been found to be unsatisfactory. More surveillance of the bottled water industry in Canada is recommended.

Seasonal Variation in the Fecal Coliform Population of Louisiana Oysters and its Relationship to Microbiological Quality

1987 ◽  
Vol 50 (7) ◽  
pp. 545-549 ◽  
Author(s):  
DIANE PAILLE ◽  
CAMERON HACKNEY ◽  
LAWERENCE REILY ◽  
MARY COLE ◽  
MARILYN KILGEN
Keyword(s):  
Escherichia Coli ◽  
Seasonal Variation ◽  
Antimicrobial Agent ◽  
Significant Relationship ◽  
Fecal Coliform ◽  
Microbiological Quality ◽  
Fecal Coliforms ◽  
Sewage Pollution ◽  
Klebsiella Species ◽  
E Coli

Seasonal variation was observed in the type of bacteria which comprised the fecal coliform population of oysters. Escherichia coli was the principal fecal coliform when water temperatures were below 22°C. Conversely, Klebsiella sp. predominated during the summer months. No significant relationship was observed between levels of E. coli and enterococci and non-E. coli fecal coliforms in oysters. Fecal coliform and E. coli levels were significantly (p >0.001) related in water. Klebsiella sp. isolated from oysters demonstrated considerably less multiple antimicrobial agent resistance than clinical isolates of K. pneumoniae. Fecal coliform-positive Klebsiella species had characteristics of environmental organisms. Results of this study suggest that high levels of non-E coli fecal coliforms in oysters harvested in the summer from beds meeting the fecal coliform water standard are not indicative of sewage pollution. Furthermore, it is suggested that the safety indicator in the guideline for oyster meats should be changed form fecal coliforms to E. coli.

scholarly journals Microbial Contamination Potential and Antibiotic Resistance Profile of Staphylococcus aureus and Escherichia coli Isolated from Ipomoea batatas Leaf

2020 ◽  
pp. 84-93
Author(s):  
Paul Yao Attien ◽  
Clément Kouassi Kouassi ◽  
Mamadou Wele ◽  
Haziz Sina ◽  
Lamine Baba- Moussa
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Ipomoea Batatas ◽  
Microbiological Quality ◽  
Leafy Vegetables ◽  
Fecal Coliforms ◽  
Diffusion Method ◽  
Human Consumption ◽  
Biochemical Tests ◽  
Disk Diffusion Method

Traditional leafy vegetables are recommended because there are important sources of nutrients and they protect against certain non-communicable diseases. This study aimed at assessing the microbiological quality of Ipomoea batatas leaves and evaluating the susceptibility to antibiotics of isolated S. aureus and E. coli strains. Heighten samples of I. batatas leaves collected were analyzed for research / enumeration of mesophilic total aerobic flora, enterobacteriaceae, yeasts, molds, fecal coliforms, fecal streptococci, Staphylococcus aureus, Escherichia coli and Salmonella strains and Escherichia coli, Staphylococcus aureus. The microorganisms were identified using appropriate medium and classical biochemical tests. The susceptibility to eleven conventional antibiotics was investigated by the disk diffusion method. The I. batatas leaves showed high contamination by various flora, in particular flora indicative of general pollution (aerobic mesophilic germs, yeasts and molds, enterobacteria) and flora of fecal origin (fecal coliforms and fecal streptococcus). In addition, the presence of pathogenic species such as Staphylococcus aureus, Escherichia coli and Salmonella sp. was noted in the samples analyzed. Globally, the highest resistance proportion has been observed with penicillin (~65%) and none of the S. aureus strains was resistant to vancomycin. From a microbiological point of view, Ipomoea batatas leaf intended for consumption is not suitable for human consumption. It is therefore important to educate producers to improve their production route in order to have better microbiological quality I. batatas leaves.

scholarly journals Genetic and Phylogenetic Diversity of Escherichia coli Strains Collected From Fecal Specimens of Patients Admitted to Zabol Hospitals

2018 ◽  
Vol 3 (4) ◽  
pp. 154-158
Author(s):  
Aliyeh Firoozkoohi ◽  
Zahra Rashki Ghalehnoo
Keyword(s):  
Escherichia Coli ◽  
Bacterial Species ◽  
Genotypic Diversity ◽  
Biochemical Tests ◽  
Phylogenetic Groups ◽  
E Coli ◽  
Random Amplification ◽  
Group A ◽  
The Difference ◽  
Tract Infections

Introduction: Escherichia coli is one of the most prevalent bacterial species which cause gastrointestinal and digestive tract infections in humans and livestock. This study examined genotypic diversity of the E. coli isolates taken from fecal specimens in Zabol using random amplification of polymorphic DNA (RAPD) method and phylogenetic background.Materials and Methods: In this study, 100 isolates were collected from human samples and identified by the common biochemical tests. The isolates were categorized into four main phylogenetic groups including group A (28 isolates), group B1 (7 isolates), group B2 (48 isolates), and group D (17 isolates). Two primers (H1 & H2) were used to study the genetic variation of E. coli and the electrophoresis band pattern was analyzed by the NTSYS.Results: The analysis of the difference in isolates using the RAPD technique showed a genetic similarity between 14% and 100%.Conclusion: The phylogenetic groups B2 and A were more frequent in fecal isolates. In addition, the number of isolates related to phylogenetic groups B1 and D was significantly lower than that of the other groups.

Microbiological performance and salmonella dynamics in a wastewater depuration pond system of southeastern spain

1995 ◽  
Vol 31 (12) ◽  
pp. 239-248 ◽  
Author(s):  
Ana Emparanza-Knörr ◽  
Francisco Torrella
Keyword(s):  
Fecal Coliform ◽  
No Reduction ◽  
Agar Medium ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Fecal Coliforms ◽  
Selective Media ◽  
E Coli ◽  
The Village ◽  
Final Effluent

The Salmonella presence and the microbiological quality indicators, total and fecal coliforms and coliphages of E. coli C, have been studied in a overloaded wastewater lagoon system treating urban wastewatrers of the village of Guardamar del Segura (Alicante, Spain). Classical microbiological technology to detect salmonellae was used, including pre-enrichment, enrichment, selective media plating and biochemical and serological confirmation. Water was physicochemically characterized according to COD, SS, temperature, pH and dissolved oxygen. The selective migration step through Rappaport-Vassiliadis semisolid agar medium was essential for the consistent detection of Salmonella in the different lagoon effluents. Total and fecal coliform levels of up to 105-106 MPN/100 ml were detected in the final effluent. High coliphage concentrations of 103-104 pfu/ml were also found in the effluent waters. Salmonella was always detected in 100 ml samples and eventually reached an order of value of 103 MPN/100 ml. Total coliform reduction was higher in the anaerobic ponds whereas fecal coliforms were more efficiently eliminated in the facultative (mostly “anoxic”) lagoons. Coliphage reduction was higher in the facultative lagoons when compared to the anaerobic ponds. On many occasions, no reduction or eventual increment of the concentration of salmonellae was detected in the effluents from the anaerobic ponds compared to concentrations of the patohogen in the influent raw wasterwaters. The possibility exists for a capacity of Salmonella to multiply in the anoxic phase of the wastewater treatment, but the presence of microorganisms in raw sewage waters which could maskSalmonella detection with the enrichment methodology employed cannot be ruled out.

scholarly journals Prevalence and Characterization of Extended-Spectrum β-Lactamase-Producing Antibiotic-Resistant Escherichia coli and Klebsiella pneumoniae in Ready-to-Eat Street Foods

Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 850
Author(s):  
Shobha Giri ◽  
Vaishnavi Kudva ◽  
Kalidas Shetty ◽  
Veena Shetty
Keyword(s):  
Escherichia Coli ◽  
Food Safety ◽  
Klebsiella Pneumoniae ◽  
Rural Areas ◽  
Significant Risk ◽  
Microbiological Quality ◽  
Resistant Bacteria ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Extended Spectrum

As the global urban populations increase with rapid migration from rural areas, ready-to-eat (RTE) street foods are posing food safety challenges where street foods are prepared with less structured food safety guidelines in small and roadside outlets. The increased presence of extended-spectrum-β-lactamase (ESBL) producing bacteria in street foods is a significant risk for human health because of its epidemiological significance. Escherichia coli and Klebsiella pneumoniae have become important and dangerous foodborne pathogens globally for their relevance to antibiotic resistance. The present study was undertaken to evaluate the potential burden of antibiotic-resistant E. coli and K. pneumoniae contaminating RTE street foods and to assess the microbiological quality of foods in a typical emerging and growing urban suburb of India where RTE street foods are rapidly establishing with public health implications. A total of 100 RTE food samples were collected of which, 22.88% were E. coli and 27.12% K. pneumoniae. The prevalence of ESBL-producing E. coli and K. pneumoniae was 25.42%, isolated mostly from chutneys, salads, paani puri, and chicken. Antimicrobial resistance was observed towards cefepime (72.9%), imipenem (55.9%), cefotaxime (52.5%), and meropenem (16.9%) with 86.44% of the isolates with MAR index above 0.22. Among β-lactamase encoding genes, blaTEM (40.68%) was the most prevalent followed by blaCTX (32.20%) and blaSHV (10.17%). blaNDM gene was detected in 20.34% of the isolates. This study indicated that contaminated RTE street foods present health risks to consumers and there is a high potential of transferring multi-drug-resistant bacteria from foods to humans and from person to person as pathogens or as commensal residents of the human gut leading to challenges for subsequent therapeutic treatments.

scholarly journals Iron Acquisition of Urinary Tract Infection Escherichia coli Involves Pathogenicity in Caenorhabditis elegans

2021 ◽  
Vol 9 (2) ◽  
pp. 310
Author(s):  
Masayuki Hashimoto ◽  
Yi-Fen Ma ◽  
Sin-Tian Wang ◽  
Chang-Shi Chen ◽  
Ching-Hao Teng
Keyword(s):  
Escherichia Coli ◽  
Urinary Tract ◽  
Caenorhabditis Elegans ◽  
Large Scale ◽  
Iron Acquisition ◽  
Infection Model ◽  
High Throughput Analysis ◽  
E Coli ◽  
C Elegans ◽  
Tract Infections

Uropathogenic Escherichia coli (UPEC) is a major bacterial pathogen that causes urinary tract infections (UTIs). The mouse is an available UTI model for studying the pathogenicity; however, Caenorhabditis elegans represents as an alternative surrogate host with the capacity for high-throughput analysis. Then, we established a simple assay for a UPEC infection model with C. elegans for large-scale screening. A total of 133 clinically isolated E. coli strains, which included UTI-associated and fecal isolates, were applied to demonstrate the simple pathogenicity assay. From the screening, several virulence factors (VFs) involved with iron acquisition (chuA, fyuA, and irp2) were significantly associated with high pathogenicity. We then evaluated whether the VFs in UPEC were involved in the pathogenicity. Mutants of E. coli UTI89 with defective iron acquisition systems were applied to a solid killing assay with C. elegans. As a result, the survival rate of C. elegans fed with the mutants significantly increased compared to when fed with the parent strain. The results demonstrated, the simple assay with C. elegans was useful as a UPEC infectious model. To our knowledge, this is the first report of the involvement of iron acquisition in the pathogenicity of UPEC in a C. elegans model.

Microbiological Quality of Fresh Blue Crabmeat, Clams and Oysters

1983 ◽  
Vol 46 (11) ◽  
pp. 978-981 ◽  
Author(s):  
B. A. WENTZ ◽  
A. P. DURAN ◽  
A. SWARTZENTRUBER ◽  
A. H. SCHWAB ◽  
R. B. READ
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Microbiological Quality ◽  
Fecal Coliforms ◽  
Geometric Means ◽  
Colony Forming Units ◽  
Plate Counts ◽  
The Mean ◽  
Eastern Oysters

The microbiological quality of fresh blue crabmeat, soft- and hardshell clams and shucked Eastern oysters was determined at the retail (crabmeat, oysters) and wholesale (clams) levels. Geometric means of aerobic plate counts incubated at 35°C were: blue crabmeat 140,000 colony-forming units (CFU)/g, hardshell clams, 950 CFU/g, softshell clams 680 CFU/g and shucked Eastern oysters 390,000 CFU/g. Coliform geometric means ranged from 3,6/100 g for hardshell clams to 21/g for blue crabmeat. Means for fecal coliforms or Escherichia coli ranged from <3/100 g for clams to 27/100 g for oysters, The mean Staphylococcus aureus count in blue crabmeat was 10/g.

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