scholarly journals Fate of Escherichia coli in dialysis device exposed into sewage influent and activated sludge

2018 ◽  
Vol 16 (3) ◽  
pp. 380-390
Author(s):  
Porsry Ung ◽  
Chanthol Peng ◽  
Sokunsreiroat Yuk ◽  
Vannak Ann ◽  
Hasika Mith ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Microbial Community ◽  
Activated Sludge ◽  
Environmental Water ◽  
Distilled Water ◽  
E Coli ◽  
Ion Concentrations ◽  
Escherichia Coli K12 ◽  
Novel Approach ◽  
Phosphate Buffered Saline

Abstract Tracing the fate of pathogens in environmental water, particularly in wastewater, with a suitable methodology is a demanding task. We investigated the fate of Escherichia coli K12 in sewage influent and activated sludge using a novel approach that involves the application of a biologically stable dialysis device. The ion concentrations inside the device could reach that of surrounding solution when it was incubated in phosphate buffered saline for 2 h. E. coli K12 above 107 CFU mL−1 (inoculated in distilled water, influent, activated sludge) were introduced into the device and incubated in influent and activated sludge for 10 days. Without indigenous microorganisms, E. coli K12 could survive even with the limited ions and nutrients concentrations in influent and activated sludge. E. coli K12 abundance in influent and activated sludge were reduced by 60 and 85%, respectively, after just 1 day. The establishment of microbial community in wastewater played an important role in reducing E. coli K12. Bacteriophage propagated in filtered influent or activated sludge when E. coli K12 was introduced, but not in raw influent or activated sludge. The methodology developed in this study can be applied in the actual environmental water to trace the fate of pathogens.

scholarly journals Streptomycin-Induced Inflammation Enhances Escherichia coli Gut Colonization Through Nitrate Respiration

mBio ◽  
2013 ◽  
Vol 4 (4) ◽  
Author(s):  
Alanna M. Spees ◽  
Tamding Wangdi ◽  
Christopher A. Lopez ◽  
Dawn D. Kingsbury ◽  
Mariana N. Xavier ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Microbial Community ◽  
Intestinal Inflammation ◽  
Anaerobic Bacteria ◽  
Nitrate Respiration ◽  
Colonization Resistance ◽  
Content Type ◽  
E Coli ◽  
Gut Colonization ◽  
Facultative Anaerobic Bacteria

ABSTRACTTreatment with streptomycin enhances the growth of human commensalEscherichia coliisolates in the mouse intestine, suggesting that the resident microbial community (microbiota) can inhibit the growth of invading microbes, a phenomenon known as “colonization resistance.” However, the precise mechanisms by which streptomycin treatment lowers colonization resistance remain obscure. Here we show that streptomycin treatment rendered mice more susceptible to the development of chemically induced colitis, raising the possibility that the antibiotic might lower colonization resistance by changing mucosal immune responses rather than by preventing microbe-microbe interactions. Investigation of the underlying mechanism revealed a mild inflammatory infiltrate in the cecal mucosa of streptomycin-treated mice, which was accompanied by elevated expression ofNos2, the gene that encodes inducible nitric oxide synthase. In turn, this inflammatory response enhanced the luminal growth ofE. coliby nitrate respiration in aNos2-dependent fashion. These data identify low-level intestinal inflammation as one of the factors responsible for the loss of resistance toE. colicolonization after streptomycin treatment.IMPORTANCEOur intestine is host to a complex microbial community that confers benefits by educating the immune system and providing niche protection. Perturbation of intestinal communities by streptomycin treatment lowers “colonization resistance” through unknown mechanisms. Here we show that streptomycin increases the inflammatory tone of the intestinal mucosa, thereby making the bowel more susceptible to dextran sulfate sodium treatment and boosting theNos2-dependent growth of commensalEscherichia coliby nitrate respiration. These data point to the generation of alternative electron acceptors as a by-product of the inflammatory host response as an important factor responsible for lowering resistance to colonization by facultative anaerobic bacteria such asE. coli.

scholarly journals Identification and Probiotic Potency Screening of Cellulolytic Bacilli Isolated from Fecal Pellets and Gastrointestinal Tract of Nypha Worm (Namalycastis rhodochorde), West Kalimantan, Indonesia

2021 ◽  
Vol 17 (2) ◽  
pp. 189-195
Author(s):  
TR Setyawati ◽  
AH Yanti ◽  
R. Kurniatuhadi
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Organic Acids ◽  
Acid Tolerance ◽  
Distilled Water ◽  
Bacterial Identification ◽  
Bacterial Isolates ◽  
Fecal Pellets ◽  
West Kalimantan ◽  
E Coli

The bacterial isolates NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolated from fecal pellets and gastrointestinal tract of nypha worms (Namalycastis rhodochorde) have cellulolytic, proteolytic activity and produce organic acids. The four isolates have the potency to be developed as probiotics in nypha worm cultivation feed. This study aims to determine the probiotics potency and identify the species of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 isolate based on 16srDNA sequence. The probiotic potency was carried out by the acid tolerance assays on distilled water and 0.3% acid bile media, and the antimicrobial testing against Escherichia coli (MF exp21.12). Bacterial identification was carried out by sequencing of 16sDNA sequence based on GeneBank data. The results showed that the bacterial isolates of NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were able to grow on 0.3% distilled water and acid bile media. However, only the NrLtF4 and NrLtF5 inhibited E. coli (MF exp21.12) with halo zones 30 mm and 18 mm, respectively. Blasting results of the 16srDNA sequences showed that the NrLtF1, NrLtF4, NrLtF5, and NrLtG2 were closely related to Bacillus wiedmannii, Brevibacterium sediminis, Bacillus proteolyticus, and Bacillus paramycoides. The nypha worm bacterial isolates have the potency to be developed as probiotics in nypha worm culture.

Prevalence of extended-spectrum β-lactamase-producing Escherichia coli and residual antimicrobials in the environment in Vietnam

2017 ◽  
Vol 18 (2) ◽  
pp. 128-135 ◽  
Author(s):  
Shinji Yamasaki ◽  
Tuyen Danh Le ◽  
Mai Quang Vien ◽  
Chinh Van Dang ◽  
Yoshimasa Yamamoto
Keyword(s):  
Escherichia Coli ◽  
Critical Role ◽  
Environmental Water ◽  
Resistant Bacteria ◽  
Human Beings ◽  
E Coli ◽  
Extended Spectrum ◽  
High Prevalence ◽  
Food Animals ◽  
High Level

AbstractEmergence and spread of antimicrobial-resistant bacteria, including extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, have become serious problems worldwide. Recent studies conducted in Vietnam revealed that ESBL-producing E. coli are widely distributed in food animals and people. CTX-M-9 and CTX-M-1 are the most prevalent β-lactamases among the identified ESBLs. Furthermore, most of the ESBL-producing E. coli isolates were multi-drug resistant. Residual antimicrobials such as sulfamethoxazole, trimethoprim, sulfadimidine, cephalexin, and sulfadiazine were also detected at a high level in both animal meats and environmental water collected from several cities, including Ho Chi Minh city and Can Tho city. These recent studies indicated that improper use of antimicrobials in animal-originated food production might contribute to the emergence and high prevalence of ESBL-producing E. coli in Vietnam. Although clonal ESBL-producing E. coli was not identified, CTX-M-55 gene-carrying plasmids with similar sizes (105–139 kb) have been commonly detected in the ESBL-producing E. coli strains isolated from various food animals and human beings. This finding strongly suggests that horizontal transfer of the CTX-M plasmid among various E. coli strains played a critical role in the emergence and high prevalence of ESBL-producing E. coli in Vietnam.

A Novel Approach To Investigate the Uptake and Internalization of Escherichia coli O157:H7 in Spinach Cultivated in Soil and Hydroponic Medium†

2009 ◽  
Vol 72 (7) ◽  
pp. 1513-1520 ◽  
Author(s):  
MANAN SHARMA ◽  
DAVID T. INGRAM ◽  
JITENDRA R. PATEL ◽  
PATRICIA D. MILLNER ◽  
XIAOLIN WANG ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Green Fluorescent Protein ◽  
Fluorescent Protein ◽  
Plasmid Vector ◽  
Green Fluorescent Protein Gene ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Novel Approach ◽  
Efficient Uptake ◽  
Green Fluorescent

Internalization of Escherichia coli O157:H7 into spinach plants through root uptake is a potential route of contamination. ATn7-based plasmid vector was used to insert a green fluorescent protein gene into the attTn7 site in the E. coli chromosome. Three green fluorescent protein–labeled E. coli inocula were used: produce outbreak O157:H7 strains RM4407 and RM5279 (inoculum 1), ground beef outbreak O157:H7 strain 86-24h11 (inoculum 2), and commensal strain HS (inoculum 3). These strains were cultivated in fecal slurries and applied at ca. 103 or 107 CFU/g to pasteurized soils in which baby spinach seedlings were planted. No E. coli was recovered by spiral plating from surface-sanitized internal tissues of spinach plants on days 0, 7, 14, 21, and 28. Inoculum 1 survived at significantly higher populations (P < 0.05) in the soil than did inoculum 3 after 14, 21, and 28 days, indicating that produce outbreak strains of E. coli O157:H7 may be less physiologically stressed in soils than are nonpathogenic E. coli isolates. Inoculum 2 applied at ca. 107 CFU/ml to hydroponic medium was consistently recovered by spiral plating from the shoot tissues of spinach plants after 14 days (3.73 log CFU per shoot) and 21 days (4.35 log CFU per shoot). Fluorescent E. coli cells were microscopically observed in root tissues in 23 (21%) of 108 spinach plants grown in inoculated soils. No internalized E. coli was microscopically observed in shoot tissue of plants grown in inoculated soil. These studies do not provide evidence for efficient uptake of E. coli O157:H7 from soil to internal plant tissue.

scholarly journals Prevalence of Colistin-Resistant, Carbapenem-Hydrolyzing Proteobacteria in Hospital Water Bodies and Out-Falls of West Bengal, India

2020 ◽  
Vol 17 (3) ◽  
pp. 1007
Author(s):  
Taniya Bardhan ◽  
Madhurima Chakraborty ◽  
Bornali Bhattacharjee
Keyword(s):  
Escherichia Coli ◽  
Bacterial Infections ◽  
West Bengal ◽  
Environmental Water ◽  
Multidrug Resistant ◽  
P Value ◽  
Hospital Wastewater ◽  
E Coli ◽  
Predominant Species ◽  
Carbapenemase Gene

Indiscriminate use of antibiotics has resulted in a catastrophic increase in the levels of antibiotic resistance in India. Hospitals treat critical bacterial infections and thus can serve as reservoirs of multidrug resistant (MDR) bacteria. Hence, this study was conducted to gauge the prevalence patterns of MDR bacteria in hospital wastewater. Water samples collected from 11 hospitals and 4 environmental sources belonging to 5 most-densely populated districts of West Bengal, India were grown on MacConkey and Eosin Methylene Blue agar. A total of 84 (hospital-associated = 70, environmental water sources = 14) isolates were characterized. The predominant species found in water from hospital-associated areas (HAA) were Acinetobacter baumannii (22.9%), Escherichia coli (28.6 %), and Klebsiella pneumoniae (25.7%). Greater than 75% of the HAA isolates were found to be mcr-1 gene negative and colistinresistant. Meropenem non-susceptibility was also high among the HAA isolates at 58.6%, with the presence of the carbapenemase gene and blaNDM in 67.1% of the non-susceptible isolates. Among the three predominant species, significantly higher numbers of E. coli isolates were found to be non-susceptible to meropenem ((80%), p-value = 0.00432) and amikacin (AK (90%), p-value = 0.00037). This study provides evidence for the presence of high numbers of colistin-resistant and carbapenem-hydrolyzing Proteobacteriain hospital wastewater.

scholarly journals Enzyme Characteristics of β-d-Galactosidase- and β-d-Glucuronidase-Positive Bacteria and Their Interference in Rapid Methods for Detection of Waterborne Coliforms andEscherichia coli

1998 ◽  
Vol 64 (3) ◽  
pp. 1018-1023 ◽  
Author(s):  
I. Tryland ◽  
L. Fiksdal
Keyword(s):  
Escherichia Coli ◽  
Enzyme Activity ◽  
Enzymatic Activity ◽  
Environmental Water ◽  
Coliform Bacteria ◽  
Galactosidase Activity ◽  
Fluorogenic Substrates ◽  
Rapid Methods ◽  
E Coli ◽  
Aerococcus Viridans

ABSTRACT Bacteria which were β-d-galactosidase and β-d-glucuronidase positive or expressed only one of these enzymes were isolated from environmental water samples. The enzymatic activity of these bacteria was measured in 25-min assays by using the fluorogenic substrates 4-methylumbelliferyl-β-d-galactoside and 4-methylumbelliferyl-β-d-glucuronide. The enzyme activity, enzyme induction, and enzyme temperature characteristics of target and nontarget bacteria in assays aimed at detecting coliform bacteria and Escherichia coli were investigated. The potential interference of false-positive bacteria was evaluated. Several of the β-d-galactosidase-positive nontarget bacteria but none of the β-d-glucuronidase-positive nontarget bacteria contained unstable enzyme at 44.5°C. The activity of target bacteria was highly inducible. Nontarget bacteria were induced much less or were not induced by the inducers used. The results revealed large variations in the enzyme levels of different β-d-galactosidase- and β-d-glucuronidase-positive bacteria. The induced and noninduced β-d-glucuronidase activities ofBacillus spp. and Aerococcus viridans were approximately the same as the activities of induced E. coli. Except for some isolates identified asAeromonas spp., all of the induced and noninduced β-d-galactosidase-positive, noncoliform isolates exhibited at least 2 log units less mean β-d-galactosidase activity than induced E. coli. The noncoliform bacteria must be present in correspondingly higher concentrations than those of target bacteria to interfere in the rapid assay for detection of coliform bacteria.

Specific Identification of Escherichia coli O157 by an Immunostick Method Using Commercially Available Antibodies

1996 ◽  
Vol 59 (6) ◽  
pp. 670-673 ◽  
Author(s):  
SHIU W. HUANG ◽  
TSUNG C. CHANG
Keyword(s):  
Escherichia Coli ◽  
Rapid Identification ◽  
Escherichia Coli O157 ◽  
Commercial Preparation ◽  
E Coli ◽  
Specificity And Sensitivity ◽  
Sandwich Enzyme Immunoassay ◽  
Antigen Antibody ◽  
Phosphate Buffered Saline ◽  
Somatic Antigens

A sandwich enzyme-immunoassay performed on plastic sticks was developed to specifically identify Escherichia coli O157. Colonies of test bacteria grown on tryptic soy agar were suspended in phosphate-buffered saline, heated in a 100°C water bath for 15 min, and incubated with the plastic sticks coated with a commercial preparation of anti-E. coli O157 antibodies at 37°C for 1.5 h. After incubation, the same antibodies labeled with peroxidase were used to produce the signal of antigen-antibody reaction. For 35 strains of E. coli O157 (among them 34 were E. coli O157:H7) tested, all produced strong reactions by the immunoassay. For 162 strains of E. coli with somatic antigens other than O157 and 38 strains of other genera tested, only one strain (Salmonella bietri) produced a false-positive reaction. The specificity and sensitivity of the immunostick assay were 100% (35/35) and 99.5% (199/200), respectively. The detection limit of the assay for E. coli O157:H7 (CCRC 15991) was about 105 CFU/ml. The method, which can be carried out within 3 h, is useful for rapid identification of suspect E. coli O157 isolated on selective media.

scholarly journals Effect of Long-Term Starvation on the Survival, Recovery, and Carbon Utilization Profiles of a Bovine Escherichia coli O157:H7 Isolate from New Zealand

2014 ◽  
Vol 80 (14) ◽  
pp. 4383-4390 ◽  
Author(s):  
Ron N. Xavier ◽  
Hugh W. Morgan ◽  
Ian R. McDonald ◽  
Helen Withers
Keyword(s):  
Escherichia Coli ◽  
New Zealand ◽  
Membrane Integrity ◽  
Nutrient Level ◽  
Carbon Utilization ◽  
Content Type ◽  
E Coli ◽  
Significant Difference ◽  
Carbon Utilization Profiles ◽  
Phosphate Buffered Saline

ABSTRACTThe ability to maintain a dual lifestyle of colonizing the ruminant gut and surviving in nonhost environments once shed is key to the success ofEscherichia coliO157:H7 as a zoonotic pathogen. Both physical and biological conditions encountered by the bacteria are likely to change during the transition between host and nonhost environments. In this study, carbon starvation at suboptimal temperatures in nonhost environments was simulated by starving a New Zealand bovineE. coliO157:H7 isolate in phosphate-buffered saline at 4 and 15°C for 84 days. Recovery of starved cells on media with different nutrient availabilities was monitored under aerobic and anaerobic conditions. We found that the New Zealand bovineE. coliO157:H7 isolate was able to maintain membrane integrity and viability over 84 days and that the level of recovery depended on the nutrient level of the recovery medium as well as the starvation temperature. In addition, a significant difference in carbon utilization was observed between starved and nonstarved cells.

Factors Influencing Attachment of Escherichia coli O157:H7 to Beef Tissues and Removal Using Selected Sanitizing Rinses‡

1996 ◽  
Vol 59 (5) ◽  
pp. 453-459 ◽  
Author(s):  
PINA M. FRATAMICO ◽  
FRANKIE J. SCHULTZ ◽  
ROBERT C. BENEDICT ◽  
ROBERT L. BUCHANAN ◽  
PETER H. COOKE
Keyword(s):  
Escherichia Coli ◽  
Acetic Acid ◽  
Surface Structures ◽  
Escherichia Coli O157 ◽  
Adipose Tissues ◽  
E Coli ◽  
Factors Influencing ◽  
Significant Difference ◽  
Phosphate Buffered Saline ◽  
Scanning Electron

Attachment of E. coli O157:H7 and E. coli K12 to beef tenderloin filet, chuck, and adipose tissues was studied. Most attachment occurred within 1 min of incubation; the number of attached organisms depended on the concentration of bacteria in the liquid inoculum. Similar levels of E. coli bound to the three types of beef tissues tested. E. coli O157:H7 was heavily piliated; however, there was no significant difference between levels of bound E. coli O157:H7 and E. coli K12, indicating that these surface structures apparently are not involved in attachment. Scanning electron photomicrographs of meat tissue and of purified collagen suggested that bacteria attached primarily to collagen fibers. Rinsing solutions consisting of 10% trisodium phosphate (TSP), 2% acetic acid (HAc), phosphate-buffered saline (PBS) and combinations of each were tested for effectiveness in reducing the number of attached E. coli. The level of bacteria removed from tenderloin tissue following TSP, HAc, or PBS rinses did not differ considerably. When beef tissues were stored at 4°C for 18 h after the various rinse combinations, TSP rinse treatments reduced the levels of E. coli K12 and O157:H7 attached to adipose tissue up to 3.4 and 2.7 log units, respectively, compared to PBS rinse treatments. Therefore, TSP may be effective for reducing populations of E. coli O157:H7 on beef carcass tissue.

scholarly journals Bacteriophages Reduce Experimental Contamination of Hard Surfaces, Tomato, Spinach, Broccoli, and Ground Beef by Escherichia coli O157:H7

2008 ◽  
Vol 74 (20) ◽  
pp. 6230-6238 ◽  
Author(s):  
Tamar Abuladze ◽  
Manrong Li ◽  
Marc Y. Menetrez ◽  
Timothy Dean ◽  
Andre Senecal ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Ground Beef ◽  
Food Samples ◽  
Significant Treatment ◽  
E Coli ◽  
Virulent Strains ◽  
Buffer Control ◽  
And Control ◽  
Phosphate Buffered Saline ◽  
Control Samples

ABSTRACT A bacteriophage cocktail (designated ECP-100) containing three Myoviridae phages lytic for Escherichia coli O157:H7 was examined for its ability to reduce experimental contamination of hard surfaces (glass coverslips and gypsum boards), tomato, spinach, broccoli, and ground beef by three virulent strains of the bacterium. The hard surfaces and foods contaminated by a mixture of three E. coli O157:H7 strains were treated with ECP-100 (test samples) or sterile phosphate-buffered saline buffer (control samples), and the efficacy of phage treatment was evaluated by comparing the number of viable E. coli organisms recovered from the test and control samples. Treatments (5 min) with the ECP-100 preparation containing three different concentrations of phages (1010, 109, and 108 PFU/ml) resulted in statistically significant reductions (P = <0.05) of 99.99%, 98%, and 94%, respectively, in the number of E. coli O157:H7 organisms recovered from the glass coverslips. Similar treatments resulted in reductions of 100%, 95%, and 85%, respectively, in the number of E. coli O157:H7 organisms recovered from the gypsum board surfaces; the reductions caused by the two most concentrated phage preparations were statistically significant. Treatment with the least concentrated preparation that elicited significantly less contamination of the hard surfaces (i.e., 109 PFU/ml) also significantly reduced the number of viable E. coli O157:H7 organisms on the four food samples. The observed reductions ranged from 94% (at 120 ± 4 h posttreatment of tomato samples) to 100% (at 24 ± 4 h posttreatment of spinach samples). The data suggest that naturally occurring bacteriophages may be useful for reducing contamination of various hard surfaces, fruits, vegetables, and ground beef by E. coli O157:H7.

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