scholarly journals The pH 6 Antigen Is an Antiphagocytic Factor Produced by Yersinia pestis Independent of Yersinia Outer Proteins and Capsule Antigen

2004 ◽  
Vol 72 (12) ◽  
pp. 7212-7219 ◽  
Author(s):  
Xiao-Zhe Huang ◽  
Luther E. Lindler
Keyword(s):  
Escherichia Coli ◽  
Yersinia Pestis ◽  
Intracellular Bacteria ◽  
Mouse Macrophage ◽  
Host Cell Line ◽  
E Coli ◽  
Significant Difference ◽  
Mouse Macrophages ◽  
Isogenic Strains ◽  
Raw264.7 Macrophage

ABSTRACT The pH 6 antigen (pH 6 Ag; PsaA) of Yersinia pestis has been shown to be a virulence factor. In this study, we set out to investigate the possible function of Y. pestis PsaA in a host cell line, RAW264.7 mouse macrophages, in order to better understand the role it might play in virulence. Y. pestis KIM5 derivatives with and without the pCD1 plasmid and their psaA isogenic counterparts and Escherichia coli HB101 and DΗ5α carrying a psaA clone or a vector control were used for macrophage infections. Macrophage-related bacteria and gentamicin-resistant intracellular bacteria generated from plate counting and direct microscopic examinations were used to evaluate these RAW264.7 macrophage infections. Y. pestis psaA isogenic strains did not show any significant difference in their abilities to associate with or bind to mouse macrophage cells. However, expression of psaA appeared to significantly reduce phagocytosis of both Y. pestis and E. coli by mouse macrophages (P < 0.05). Furthermore, we found that complementation of psaA mutant Y. pestis strains could completely restore the ability of the bacteria to resist phagocytosis. Fluorescence microscopy following differential labeling of intracellular and extracellular Y. pestis revealed that significantly lower numbers of psaA-expressing bacteria were located inside the macrophages. Enhanced phagocytosis resistance was specific for bacteria expressing psaA and did not influence the ability of the macrophages to engulf other bacteria. Our data demonstrate that Y. pestis pH 6 Ag does not enhance adhesion to mouse macrophages but rather promotes resistance to phagocytosis.

scholarly journals Distribution of Sulfonamide Resistance Genes in Escherichia coli and Salmonella Isolates from Swine and Chickens at Abattoirs in Ontario and Québec, Canada

2009 ◽  
Vol 75 (18) ◽  
pp. 5999-6001 ◽  
Author(s):  
Gosia K. Kozak ◽  
David L. Pearl ◽  
Julia Parkman ◽  
Richard J. Reid-Smith ◽  
Anne Deckert ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Resistance Genes ◽  
E Coli ◽  
Significant Difference ◽  
Sulfonamide Resistance ◽  
Sulfonamide Resistance Genes

ABSTRACT Sulfonamide-resistant Escherichia coli and Salmonella isolates from pigs and chickens in Ontario and Québec were screened for sul1, sul2, and sul3 by PCR. Each sul gene was distributed differently across populations, with a significant difference between distribution in commensal E. coli and Salmonella isolates and sul3 restricted mainly to porcine E. coli isolates.

scholarly journals Characterization of Escherichia coli DNA Lesions Generated within J774 Macrophages

2000 ◽  
Vol 182 (18) ◽  
pp. 5225-5230 ◽  
Author(s):  
Eliana Schlosser-Silverman ◽  
Maya Elgrably-Weiss ◽  
Ilan Rosenshine ◽  
Ron Kohen ◽  
Shoshy Altuvia
Keyword(s):  
Escherichia Coli ◽  
Dna Damage ◽  
Respiratory Burst ◽  
Defense Mechanism ◽  
Dna Lesions ◽  
Intracellular Bacteria ◽  
Bacterial Killing ◽  
Strand Breaks ◽  
E Coli ◽  
Dna Strand

ABSTRACT Macrophages are armed with multiple oxygen-dependent and -independent bactericidal properties. However, the respiratory burst, generating reactive oxygen species, is believed to be a major cause of bacterial killing. We exploited the susceptibility of Escherichia coli in macrophages to characterize the effects of the respiratory burst on intracellular bacteria. We show that E. coli strains recovered from J774 macrophages exhibit high rates of mutations. We report that the DNA damage generated inside macrophages includes DNA strand breaks and the modification 8-oxo-2′-deoxyguanosine, which are typical oxidative lesions. Interestingly, we found that under these conditions, early in the infection the majority of E. coli cells are viable but gene expression is inhibited. Our findings demonstrate that macrophages can cause severe DNA damage to intracellular bacteria. Our results also suggest that protection against the macrophage-induced DNA damage is an important component of the bacterial defense mechanism within macrophages.

scholarly journals Lactic Acid Bacteria (Lactobacillus bulgaricus and Streptococcus thermophillus) in Yogurt Inhibit the Growth of Escherichia coli, Salmonella typhimurium, and Shigella sp. In Vitro

2021 ◽  
Vol 31 (4) ◽  
pp. 2
Author(s):  
IDSAP Peramiarti
Keyword(s):  
Escherichia Coli ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Salmonella Typhimurium ◽  
Pathogenic Bacteria ◽  
Test Method ◽  
P Value ◽  
E Coli ◽  
Significant Difference

Diarrhea is defecation with a frequency more often than usual (three times or more) a day (10 mL/kg/day) with a soft or liquid consistency, even in the form of water alone. Pathogenic bacteria, such as Escherichia coli, Salmonella typhimurium, and Shigella sp., play a role in many cases, to which antibiotics are prescribed as the first-line therapy. However, since antibiotic resistance cases are often found, preventive therapies are needed, such as consuming yogurt, which is produced through a fermentation process by lactic acid bacteria (LAB). This research aimed to determine the activity of lactic acid bacteria (Liactobacillus bulgaricus and Streptococcus thermophilus) in yogurt in inhibiting the growth of the pathogenic bacteria E. coli, S. typhimurium, and Shigella sp. The research applied in vitro with the liquid dilution test method and the true experimental design research method with post-test-only and control group design. The design was used to see the inhibitory effect of yogurt LAB on the growth of E. coli, S. typhimurium, and Shigell sp. to compare the effect of several different yogurt concentrations, namely 20%, 40%, 60%, and 80%. The results of the Least Significance Different analysis showed that there was a significant difference between yogurt with a concentration of 0% and that with various concentrations in inhibiting the growth of E. coli, S. typhimurium, and Shigella sp. with a p-value of &lt;0.05. Whereas, there was no significant difference in the various concentrations of yogurt in inhibiting the growth of the three kinds of bacteria with a p-value of &gt; 0.05.<p class="Default" align="center"> </p>

Frequency of iss and irp2 genes by PCR method in Escherichia coli isolated from poultry with colibacillosis in comparison with healthy chicken in poultry farms of Zabol, South East of Iran

2017 ◽  
Vol 20 (2) ◽  
pp. 363-367 ◽  
Author(s):  
M. S. Sadeghi Bonjar ◽  
S. Salari ◽  
M. Jahantigh ◽  
A. Rashki
Keyword(s):  
Escherichia Coli ◽  
Border Region ◽  
Special Trait ◽  
E Coli ◽  
Significant Difference ◽  
East Of Iran ◽  
Liver And Kidney ◽  
Chicken Feces ◽  
Pcr Method ◽  
Control Study

AbstractThere is no special trait for differentiation of Avian PathogenicEscherichia colifrom Avian FecalEscherichia coli. This investigation is aimed, as a case control study, to evaluate and compare the frequency ofissandirp2in 43 AFEC strains and also 40 and 56E. colistrains isolated from the liver and kidney of chickens with colibacillosis, respectively, farmed in Zabol, as a border region of Iran, by PCR. 86.9% and 37.2% of isolates collected from chickens with colibacillosis and feces samples obtained from healthy chickens were positive forissgene, respectively (P<0.05). On average, 59.3% ofE. colistrains isolated from colibacillosis haveirp2gene while 27.9% of isolates from the feces of healthy birds were positive (P<0.05). 52.15% of isolates from colibacillosis and 19.62% of isolates from healthy chicken feces were positive for both genes, with statistical significant difference (p<0.05). This marked difference in the distribution ofissandirp2genes makes these two genes good markers to differentiate AFEC and APEC strains especially in Sistan region to improve colibacillosis control measurements.

Simultaneous Enrichment of Shiga Toxin–Producing Escherichia coli O157 and O26 and Salmonella in Food Samples Using Universal Preenrichment Broth

2009 ◽  
Vol 72 (10) ◽  
pp. 2065-2070 ◽  
Author(s):  
MASASHI KANKI ◽  
KAZUKO SETO ◽  
JUNKO SAKATA ◽  
TETSUYA HARADA ◽  
YUKO KUMEDA
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Food Samples ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Significant Difference ◽  
Peptone Water ◽  
Radish Sprouts ◽  
Pork Samples ◽  
Better Than

Universal preenrichment broth (UPB) was compared with modified Escherichia coli broth with novobiocin (mEC+n) for enrichment of Shiga toxin–producing E. coli O157 and O26, and with buffered peptone water (BPW) for preenrichment of Salmonella enterica. Ten strains each of the three pathogens were inoculated into beef and radish sprouts following thermal, freezing, or no treatment. With regard to O157 and O26, UPB incubated at 42°C recovered significantly more cells from inoculated beef than UPB at 35°C and from radish sprout samples than UPB at 35°C and mEC+n. With regard to Salmonella, UPB incubated at 42°C was as effective as UPB at 35°C and BPW at recovering cells from beef and radish sprout samples. No significant difference was noted between the effectiveness of UPB at 42°C and UPB at 35°C or BPW in the recovery of Salmonella from 205 naturally contaminated poultry samples. By using UPB at 42°C, one O157:H7 strain was isolated from the mixed offal of 53 beef samples, 6 cattle offal samples, and 50 pork samples all contaminated naturally, with no pathogen inoculation. The present study found that UPB incubated at 42°C was as effective as, or better than, mEC+n for enrichment of O157 and O26 and comparable to BPW for preenrichment of Salmonella. These findings suggest that a great deal of labor, time, samples, and space may be saved if O157, O26, and Salmonella are enriched simultaneously with UPB at 42°C.

scholarly journals Clinical and Economic Impact of Third-Generation Cephalosporin-Resistant Infection or Colonization Caused by Escherichia coli and Klebsiella pneumoniae: A Multicenter Study in China

2020 ◽  
Vol 17 (24) ◽  
pp. 9285
Author(s):  
Xuemei Zhen ◽  
Cecilia Stålsby Lundborg ◽  
Xueshan Sun ◽  
Xiaoqian Hu ◽  
Hengjin Dong
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Hospital Mortality ◽  
Multicenter Study ◽  
Generation Cephalosporin ◽  
Total Hospital Cost ◽  
Third Generation ◽  
E Coli ◽  
Significant Difference ◽  
The Impact

Quantifying economic and clinical outcomes for interventions could help to reduce third-generation cephalosporin resistance and Escherichia coli or Klebsiella pneumoniae. We aimed to compare the differences in clinical and economic burden between third-generation cephalosporin-resistant E. coli (3GCREC) and third-generation cephalosporin-susceptible E. coli (3GCSEC) cases, and between third-generation cephalosporin-resistant K. pneumoniae (3GCRKP) and third-generation cephalosporin-susceptible K. pneumoniae (3GCSKP) cases. A retrospective and multicenter study was conducted. We collected data from electronic medical records for patients who had clinical samples positive for E. coli or K. pneumoniae isolates during 2013 and 2015. Propensity score matching (PSM) was conducted to minimize the impact of potential confounding variables, including age, sex, insurance, number of diagnoses, Charlson comorbidity index, admission to intensive care unit, surgery, and comorbidities. We also repeated the PSM including length of stay (LOS) before culture. The main indicators included economic costs, LOS and hospital mortality. The proportions of 3GCREC and 3GCRKP in the sampled hospitals were 44.3% and 32.5%, respectively. In the two PSM methods, 1804 pairs and 1521 pairs were generated, and 1815 pairs and 1617 pairs were obtained, respectively. Compared with susceptible cases, those with 3GCREC and 3GCRKP were associated with significantly increased total hospital cost and excess LOS. Inpatients with 3GCRKP were significantly associated with higher hospital mortality compared with 3GCSKP cases, however, there was no significant difference between 3GCREC and 3GCSEC cases. Cost reduction and outcome improvement could be achieved through a preventative approach in terms of both antimicrobial stewardship and preventing the transmission of organisms.

Field Evaluation of the MUG Assay for Enumerating Escherichia coli in Seawater and Oysters from Southeastern United States

1991 ◽  
Vol 54 (4) ◽  
pp. 246-248 ◽  
Author(s):  
MILES L. MOTES ◽  
JAMES T. PEELER
Keyword(s):  
United States ◽  
Escherichia Coli ◽  
Southeastern United States ◽  
Field Evaluation ◽  
Fecal Coliforms ◽  
American Public Health Association ◽  
Suitable Alternative ◽  
E Coli ◽  
Significant Difference ◽  
Health Association

Oysters and seawater collected from the southeastern United States were examined for fecal coliforms and Escherichia coli, using the current procedure of the American Public Health Association (APHA) and the fluorogenic 4-methylumbelliferyl-β-D-glucuronide (MUG) modified APHA procedure. After the presence of E. coli in both methods was confirmed by conventional IMViC procedures, there was no significant difference between method means at the α = 0.05 level. In oysters, low confirmation rates of 67 and 77% were observed by the APHA and the MUG methods, respectively. Seawater had the greatest confirmation rates (95%) by the MUG method. The MUG method may be a suitable alternative to the current APHA method for the microbiological evaluation of oysters and seawater.

Incidence of Antibiotic Resistant Escherichia Coli in Iraqi Milk Products

1990 ◽  
Vol 53 (10) ◽  
pp. 846-848
Author(s):  
F. M. ABBAR ◽  
H. KH. KADDER
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Agents ◽  
Resistance Pattern ◽  
Antibiotic Resistant ◽  
Milk Products ◽  
E Coli ◽  
Antimicrobial Sensitivity ◽  
Significant Difference ◽  
Resistance To Penicillin ◽  
Overall Resistance

The antimicrobial sensitivity of 430 Escherichia coli strains isolated from three types of locally processed Iraqi milk products was determined. Four hundred and one (93.2%) isolates were resistant to one or more antimicrobial agents, and only 29 (6.7%) isolates were sensitive to all 12 agents tested. The incidence of resistant E. coli was 95.5%, 90.4% and 84.4% in isolates from cheese, kishfa, and gaymer, respectively. There was no significant difference in resistance among E. coli strains from various milk products. Overall, resistance to penicillin (92.3%), erythromycin (75.8%), cephaloridine (71.9%), ampicillin (57.7%), and tetracycline (37%) was most frequent, whereas isolates were least resistant to kanamycin (7.2%), chloramphenicol (8.1%), nalidixic acid (8.6%), gentamycin (9%), streptomycin (12.5%), trimethoprim (14%), and colistin (18%). The predominant antimicrobial resistance pattern was penicillin, ampicillin, cephaloridine, and erythromycin detected in 77 (18%). The high resistance of E. coli strains isolated from product samples was suggestive of misuse of these drugs in Iraq.

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.

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