scholarly journals Survival and growth of Vibrio cholerae and Escherichia coli in treated groundwater consumed in northern Cameroon

2020 ◽  
Vol 10 (12) ◽  
Author(s):  
Moussa Djaouda ◽  
Zoua Wadoubé ◽  
Odile Baponwa ◽  
Soumayyata Youssoufa ◽  
Bouba Gaké ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Mineral Water ◽  
Tap Water ◽  
Well Water ◽  
Bacterial Strains ◽  
E Coli ◽  
Northern Cameroon ◽  
Oral Pathogens ◽  
Survival And Growth

AbstractTreated groundwater is a major source of drinking water but subject to potential contamination of fecal–oral pathogens. To understand ecology of the pathogens in the treated water, this study evaluated survival and growth of Vibrio cholerae and Escherichia coli in the treated groundwater in northern Cameroon. E. coli and V. cholerae O1 were isolated from human feces. Water samples were collected from the following sources: a well, tap water from the Cameroon Water Utilities Company, and mineral and borehole waters sold in Maroua, respectively. These waters were treated by one or more processes, including autoclaving, filtration, chlorination and ozonation and were used for the constitution of microcosms. E. coli and V. cholerae were inoculated into each microcosm at respective concentrations of 50 CFU/10 mL (separately) and 40 CFU/10 mL each (together). All bacterial strains survived in all microcosms were used. The ability to survive and grow varied with the bacterial strain and microcosm (P < 0.05). When inoculated separately into the same type of microcosms, V. cholerae grew faster than E. coli with the latter even showing decrease in concentration in mineral water. When inoculated together, V. cholerae grew faster than E. coli, except in autoclaved well water and filtered and autoclaved well water. Autochthonous ultramicroflora inhibited the growth of E. coli in filtered well water (P < 0.05).

scholarly journals Survival and Growth of Vibrio cholerae, Escherichia coli, and Salmonella Spp. in Well Water Used for Drinking Purposes in Garoua (North Cameroon)

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Moussa Djaouda ◽  
Bouba Gaké ◽  
Daniel Ebang Menye ◽  
Serge Hubert Zébazé Togouet ◽  
Moïse Nola ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Well Water ◽  
Bacterial Survival ◽  
Bacterial Strains ◽  
Salmonella Spp ◽  
E Coli ◽  
Antimicrobial Substances ◽  
Survival And Growth ◽  
Faecal Bacteria

The ability of strains of faecal bacteria (Vibrio cholerae, Escherichia coli ATCC 25922, and four strains of Salmonella isolated, resp., from well water, pig, poultry, and human urine in Garoua) to survive or grow in well water microcosms was compared. Water samples were obtained from two wells in Garoua (north Cameroun). Autoclaving at 121°C for 15 min and filtration through 0.2 µm filter were used to make microcosms. Microcosms were constituted of unfiltered-autoclaved, filtered-nonautoclaved, and filtered-autoclaved well waters. Bacterial strains were inoculated at initial cell concentration of 3 Log10CFU/mL. All strains were able to survive/grow in used microcosms, and a maximal concentration of 5.61 Log10CFU/mL was observed. Survival abilities were strain and microcosm dependent. The declines were more pronounced in filtered-nonautoclaved water than in the other microcosms. E. coli and Salmonella sp. (poultry strain) lowered to undetectable levels (<1 Log10CFU/mL) after two days of water storage. V. cholera decreased over time, but surviving cells persisted for longer period in filtered-nonautoclaved water from well W1 (1.91 Log10CFU/mL) and well W2 (2.09 Log10CFU/mL). Competition for nutrients and/or thermolabile antimicrobial substances synthesized by “ultramicrocells” or by the autochthonous bacteria retained by the filter might affect the bacterial survival.

scholarly journals Diversity, virulence and antibiogram traits of Escherichia coli recovered from potable water sources in Gharbia, Egypt

2020 ◽  
Vol 18 (3) ◽  
pp. 430-438
Author(s):  
Walid Elmonir ◽  
Etab Mohamed Abo Remela ◽  
Yasmine Alwakil
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Water Samples ◽  
Potable Water ◽  
Multiple Drug Resistance ◽  
Tap Water ◽  
Water Sources ◽  
Multiple Drug ◽  
Well Water ◽  
E Coli

Abstract This study aimed to assess the public health risk of coliforms and Escherichia coli contamination of potable water sources in Egypt. A total of 150 water samples (100 tap and 50 well) were collected from five districts in Gharbia governorate, Egypt. High rates of coliforms contamination were recorded in 52 and 76% of examined tap and well water samples, respectively. E. coli strains were detected in 16% of the water samples (15% tap water and 18% well water; 23.7% rural and 8.1% urban). Rural water sources were 3.5 times more likely to be contaminated than urban sources (P = 0.01). Eight (33.3%) E. coli isolates were Shiga toxin-producing E. coli (STEC). Multiple drug resistance (MDR) was observed for 62.5% of the isolates. Seven (29.2%) E. coli isolates harboured at least one of the extended-spectrum beta-lactamase (ESBL) genes. The majority (87.5%) of the STEC isolates were MDRs and harboured ESBL genes. STEC isolates were significantly more likely to resist six classes of antibiotics than non-STEC isolates. This is the first report of potable water contamination with MDR-STEC in Egypt. This study highlights an alarming public health threat that necessitates preventive interventions for public and environmental safety.

scholarly journals Vibrio cholerae Triggers SOS and Mutagenesis in Response to a Wide Range of Antibiotics: a Route towards Multiresistance

2011 ◽  
Vol 55 (5) ◽  
pp. 2438-2441 ◽  
Author(s):  
Zeynep Baharoglu ◽  
Didier Mazel
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Vibrio Cholerae ◽  
Fluorescent Protein ◽  
Resistance Development ◽  
Content Type ◽  
E Coli ◽  
Wide Range ◽  
Green Fluorescent ◽  
Regulated Promoters

ABSTRACTAntibiotic resistance development has been linked to the bacterial SOS stress response. InEscherichia coli, fluoroquinolones are known to induce SOS, whereas other antibiotics, such as aminoglycosides, tetracycline, and chloramphenicol, do not. Here we address whether various antibiotics induce SOS inVibrio cholerae. Reporter green fluorescent protein (GFP) fusions were used to measure the response of SOS-regulated promoters to subinhibitory concentrations of antibiotics. We show that unlike the situation withE. coli, all these antibiotics induce SOS inV. cholerae.

scholarly journals Escherichia coli Contamination of Vegetables Grown in Soils Fertilized with Noncomposted Bovine Manure: Garden-Scale Studies

2004 ◽  
Vol 70 (11) ◽  
pp. 6420-6427 ◽  
Author(s):  
Steven C. Ingham ◽  
Jill A. Losinski ◽  
Matthew P. Andrews ◽  
Jane E. Breuer ◽  
Jeffry R. Breuer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Tap Water ◽  
Silty Clay ◽  
Silt Loam ◽  
Silty Clay Loam ◽  
Manure Application ◽  
E Coli ◽  
Fertilized Soil ◽  
Low Levels ◽  
National Organic Program

ABSTRACT In this study we tested the validity of the National Organic Program (NOP) requirement for a ≥120-day interval between application of noncomposted manure and harvesting of vegetables grown in manure-fertilized soil. Noncomposted bovine manure was applied to 9.3-m2 plots at three Wisconsin sites (loamy sand, silt loam, and silty clay loam) prior to spring and summer planting of carrots, radishes, and lettuce. Soil and washed (30 s under running tap water) vegetables were analyzed for indigenous Escherichia coli. Within 90 days, the level of E. coli in manure-fertilized soil generally decreased by about 3 log CFU/g from initial levels of 4.2 to 4.4 log CFU/g. Low levels of E. coli generally persisted in manure-fertilized soil for more than 100 days and were detected in enriched soil from all three sites 132 to 168 days after manure application. For carrots and lettuce, at least one enrichment-negative sample was obtained ≤100 days after manure application for 63 and 88% of the treatments, respectively. The current ≥120-day limit provided an even greater likelihood of not detecting E. coli on carrots (≥1 enrichment-negative result for 100% of the treatments). The rapid maturation of radishes prevented conclusive evaluation of a 100- or 120-day application-to-harvest interval. The absolute absence of E. coli from vegetables harvested from manure-fertilized Wisconsin soils may not be ensured solely by adherence to the NOP ≥120-day limit. Unless pathogens are far better at colonizing vegetables than indigenous E. coli strains are, it appears that the risk of contamination for vegetables grown in Wisconsin soils would be elevated only slightly by reducing the NOP requirement to ≥100 days.

A Comparison of Hand Washing Techniques To Remove Escherichia coli and Caliciviruses under Natural or Artificial Fingernails

2003 ◽  
Vol 66 (12) ◽  
pp. 2296-2301 ◽  
Author(s):  
CHIA-MIN LIN ◽  
FONE-MAO WU ◽  
HOI-KYUNG KIM ◽  
MICHAEL P. DOYLE ◽  
BARRY S. MICHAELS ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Tap Water ◽  
Hand Washing ◽  
Microbial Populations ◽  
Liquid Soap ◽  
E Coli ◽  
Hand Sanitizer ◽  
Before And After ◽  
Escherichia Coli Jm109 ◽  
Viral Indicators

Compared with other parts of the hand, the area beneath fingernails harbors the most microorganisms and is most difficult to clean. Artificial fingernails, which are usually long and polished, reportedly harbor higher microbial populations than natural nails. Hence, the efficacy of different hand washing methods for removing microbes from natural and artificial fingernails was evaluated. Strains of nonpathogenic Escherichia coli JM109 and feline calicivirus (FCV) strain F9 were used as bacterial and viral indicators, respectively. Volunteers with artificial or natural nails were artificially contaminated with ground beef containing E. coli JM109 or artificial feces containing FCV. Volunteers washed their hands with tap water, regular liquid soap, antibacterial liquid soap, alcohol-based hand sanitizer gel, regular liquid soap followed by alcohol gel, or regular liquid soap plus a nailbrush. The greatest reduction of inoculated microbial populations was obtained by washing with liquid soap plus a nailbrush, and the least reduction was obtained by rubbing hands with alcohol gel. Lower but not significantly different (P &gt; 0.05) reductions of E. coli and FCV counts were obtained from beneath artificial than from natural fingernails. However, significantly (P ≤ 0.05) higher E. coli and FCV counts were recovered from hands with artificial nails than from natural nails before and after hand washing. In addition, microbial cell numbers were correlated with fingernail length, with greater numbers beneath fingernails with longer nails. These results indicate that best practices for fingernail sanitation of food handlers are to maintain short fingernails and scrub fingernails with soap and a nailbrush when washing hands.

Effects of Water Source, Dilution, Storage, and Bacterial and Fecal Loads on the Efficacy of Electrolyzed Oxidizing Water for the Control of Escherichia coli O157:H7

2004 ◽  
Vol 67 (7) ◽  
pp. 1377-1383 ◽  
Author(s):  
S. M. L. STEVENSON ◽  
S. R. COOK ◽  
S. J. BACH ◽  
T. A. McALLISTER
Keyword(s):  
Escherichia Coli ◽  
Bactericidal Activity ◽  
Storage Temperature ◽  
Uv Light ◽  
Tap Water ◽  
Organic Matter Content ◽  
Water Source ◽  
Deionized Water ◽  
Escherichia Coli O157 ◽  
E Coli

To evaluate the potential of using electrolyzed oxidizing (EO) water for controlling Escherichia coli O157:H7 in water for livestock, the effects of water source, electrolyte concentration, dilution, storage conditions, and bacterial or fecal load on the oxidative reduction potential (ORP) and bactericidal activity of EO water were investigated. Anode and combined (7:3 anode:cathode, vol/vol) EO waters reduced the pH and increased the ORP of deionized water, whereas cathode EO water increased pH and lowered ORP. Minimum concentrations (vol/vol) of anode and combined EO waters required to kill 104 CFU/ml planktonic suspensions of E. coli O157:H7 strain H4420 were 0.5 and 2.0%, respectively. Cathode EO water did not inhibit H4420 at concentrations up to 16% (vol/vol). Higher concentrations of anode or combined EO water were required to elevate the ORP of irrigation or chlorinated tap water compared with that of deionized water. Addition of feces to EO water products (0.5% anode or 2.0% combined, vol/vol) significantly reduced (P &lt; 0.001) their ORP values to &lt;700 mV in all water types. A relationship between ORP and bactericidal activity of EO water was observed. The dilute EO waters retained the capacity to eliminate a 104 CFU/ml inoculation of E. coli O157:H7 H4420 for at least 70 h regardless of exposure to UV light or storage temperature (4 versus 24°C). At 95 h and beyond, UV exposure reduced ORP, significantly more so (P &lt; 0.05) in open than in closed containers. Bactericidal activity of EO products (anode or combined) was lost in samples in which ORP value had fallen to ≤848 mV. When stored in the dark, the diluted EO waters retained an ORP of &gt;848 mV and bactericidal efficacy for at least 125 h; with refrigeration (4°C), these conditions were retained for at least 180 h. Results suggest that EO water may be an effective means by which to control E. coli O157:H7 in livestock water with low organic matter content.

Enterohemorrhagic Escherichia coli Colony Check Assay for the Identification of Serogroups O26, O45, O103, O111, O121, O145, and O157 Colonies Isolated on Plating Media

2014 ◽  
Vol 77 (7) ◽  
pp. 1212-1218 ◽  
Author(s):  
BURTON BLAIS ◽  
MYLÈNE DESCHÊNES ◽  
GEORGE HUSZCZYNSKI ◽  
MARTINE GAUTHIER
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
High Throughput Screening ◽  
Enterohemorrhagic Escherichia Coli ◽  
Test Results ◽  
Bacterial Strains ◽  
Enrichment Broth ◽  
Substrate Solution ◽  
E Coli ◽  
Assay Performance

A simple immunoenzymatic enterohemorrhagic Escherichia coli (EHEC) colony check (ECC) assay was developed for the presumptive identification of priority EHEC colonies isolated on plating media from enrichment broth cultures of foods. With this approach, lipopolysaccharide extracted from a colony is spotted on the grid of a polymyxin-coated polyester cloth strip, and bound E. coli serogroup O26, O45, O103, O111, O121, O145, and O157 antigens are subsequently detected by sequential reactions with a pool of commercially available peroxidase-conjugated goat antibodies and tetramethylbenzidine substrate solution. Each strip can accommodate up to 15 colonies, and test results are available within 30 min. Assay performance was verified using colonies from a total of 73 target EHEC isolates covering the range of designated priority serogroups (all of which were reactive), 41 nontarget E. coli isolates including several nontarget Shiga toxin–producing E. coli serogroups (all unreactive), and 33 non–E. coli strains (all unreactive except two bacterial strains possessing O-antigenic structures in common with those of the priority EHEC). The ECC assay was reactive with target colonies grown on several types of selective and nonselective plating media designed for their cultivation. These results support the use of the ECC assay for high-throughput screening of colonies isolated on plating media for detecting priority EHEC strains in foods.

scholarly journals Analysis of crystalline and solution states of ligand-free spermidine N-acetyltransferase (SpeG) from Escherichia coli

2019 ◽  
Vol 75 (6) ◽  
pp. 545-553 ◽  
Author(s):  
Ekaterina V. Filippova ◽  
Steven Weigand ◽  
Olga Kiryukhina ◽  
Alan J. Wolfe ◽  
Wayne F. Anderson
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Crystal Structures ◽  
Coenzyme A ◽  
Amino Group ◽  
Acetyl Coenzyme A ◽  
E Coli ◽  
Ligand Free ◽  
Acetyl Group ◽  
Terminal Amino

Spermidine N-acetyltransferase (SpeG) transfers an acetyl group from acetyl-coenzyme A to an N-terminal amino group of intracellular spermidine. This acetylation inactivates spermidine, reducing the polyamine toxicity that tends to occur under certain chemical and physical stresses. The structure of the SpeG protein from Vibrio cholerae has been characterized: while the monomer possesses a structural fold similar to those of other Gcn5-related N-acetyltransferase superfamily members, its dodecameric structure remains exceptional. In this paper, structural analyses of SpeG isolated from Escherichia coli are described. Like V. cholerae SpeG, E. coli SpeG forms dodecamers, as revealed by two crystal structures of the ligand-free E. coli SpeG dodecamer determined at 1.75 and 2.9 Å resolution. Although both V. cholerae SpeG and E. coli SpeG can adopt an asymmetric open dodecameric state, solution analysis showed that the oligomeric composition of ligand-free E. coli SpeG differs from that of ligand-free V. cholerae SpeG. Based on these data, it is proposed that the equilibrium balance of SpeG oligomers in the absence of ligands differs from one species to another and thus might be important for SpeG function.

Fate of Escherichia coli O157:H7 in the Presence of Indigenous Microorganisms on Commercially Packaged Baby Spinach, as Impacted by Storage Temperature and Time†

2009 ◽  
Vol 72 (10) ◽  
pp. 2038-2045 ◽  
Author(s):  
YAGUANG LUO ◽  
QIANG HE ◽  
JAMES L. McEVOY ◽  
WILLIAM S. CONWAY
Keyword(s):  
Escherichia Coli ◽  
Product Quality ◽  
Elevated Temperatures ◽  
Storage Temperature ◽  
Escherichia Coli O157 ◽  
Indigenous Microorganisms ◽  
E Coli ◽  
Psychrotrophic Bacteria ◽  
Survival And Growth

This study investigated the effect of storage temperature and time on the survival and growth of Escherichia coli O157:H7, the growth of indigenous microorganisms, and the changes in product quality of packaged baby spinach. Commercial packages of spinach within 2 days of processing were cut open at one end, sprayed with fine mists of E. coli O157:H7 inoculum, resealed, and then stored at 1, 5, 8, and 12°C for 12 days until their labeled best-if-used-by dates. Microbial enumeration and product quality evaluation were conducted on day(s) 0, 3, 6, 9, and 12 postinoculation. Spinach held at 12°C supported significant (P &lt; 0.001) E. coli O157:H7 growth, with a 1.0-log CFU/g increase within 3 days postinoculation, which was followed by additional growth during continued storage. E. coli O157:H7 grew slowly when held at 8°C, with a significant (P &lt; 0.01) level of growth reached after 6 days of storage. However, on products held at 1 and 5°C, E. coli O157:H7 populations declined significantly (P &lt; 0.01 and P &lt; 0.001, respectively) within 3 days of storage. Aerobic mesophilic bacteria, psychrotrophic bacteria, and yeast and mold populations increased significantly at all storage temperatures, with more growth on products held at elevated temperatures. Product quality scores remained high within the first 6 days of storage, with a sharp decline noted on samples held at 12°C on day 9. Results suggest that E. coli O157:H7 can grow significantly on commercially packaged spinach held at 8°C or above before significant product quality deterioration occurs.

scholarly journals Utilization of Mn-Doped ZnSe/ZnS Core/Shell Quantum Dots for Rapid Detection of Escherichia coli O157:H7 and Methicillin-Resistant Staphylococcus aureus

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Thi-Diem Bui ◽  
Quang-Liem Nguyen ◽  
Thi-Bich Luong ◽  
Van Thuan Le ◽  
Van-Dat Doan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Quantum Dots ◽  
Fluorescent Labeling ◽  
Core Shell ◽  
Bacterial Cells ◽  
Bacterial Strains ◽  
Methicillin Resistant ◽  
E Coli ◽  
Mn Doped

In this study, Mn-doped ZnSe/ZnS core/shell quantum dots (CSQDs) were synthesized in aqueous solution using polyethylene glycol as a surface stabilizer and successfully applied in the detection of Escherichia coli O157:H7 and methicillin-resistant Staphylococcus aureus (MRSA) for the first time. The CSQDs were conjugated with anti-E. coli antibody and anti-MRSA antibody via protein A supported by 1-ethyl-3-(-3-dimethylaminopropyl)carbodiimide hydrochloride for fluorescent labeling of the intact bacterial cells. The detection was performed for the bacterial strains cultivated in Luria-Bertani liquid medium. The obtained results indicate that E. coli O157:H7 and MRSA can be detected within 30 min at a high sensitivity of 101 CFU/mL. This labeling method based on the highly fluorescent CSQDs may have great potential for use in the food industry to check and prevent outbreaks of foodborne illness.

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