β-Hydroxybutyrate Abrogates Formation of Bovine Neutrophil Extracellular Traps and Bactericidal Activity against Mammary Pathogenic Escherichia coli

ABSTRACT Escherichia coli is an important bacterial species isolated from bovine mastitis. The rate of neutrophil recruitment into the mammary gland and their bactericidal activity largely affect the severity and outcome of the disease. Ketosis is a common metabolic disease, and affected dairy cows are known to have increased risk for mastitis and other infectious conditions. The disease is associated with high blood and milk levels of β-hydroxybutyrate (BHBA), previously shown to negatively affect neutrophil function by unknown mechanisms. We show here that the mammary pathogenic E. coli strain P4 activates normal bovine neutrophils to form neutrophil extracellular traps (NETs), which are highly bactericidal against this organism. Preincubation of these neutrophils with increasing concentrations (0.1 to 8 mmol/liter) of BHBA caused a fivefold decrease of E. coli P4 phagocytosis, though intracellular killing was unaffected. Furthermore, BHBA caused a 10-fold decrease in the NETs formed by E. coli P4-activated neutrophils and a similar decrease in NET bactericidal activity against this organism. These negative effects of BHBA on bovine neutrophils might explain the increased susceptibility of ketotic cows to mastitis and other infectious conditions.

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Characterization of Escherichia coli Strains Derived from Cow Milk of Subclinical and Clinical Cases of Mastitis

Applied Sciences ◽

10.3390/app11020541 ◽

2021 ◽

Vol 11 (2) ◽

pp. 541

Author(s):

Katarzyna Grudlewska-Buda ◽

Krzysztof Skowron ◽

Ewa Wałecka-Zacharska ◽

Natalia Wiktorczyk-Kapischke ◽

Jarosław Bystroń ◽

...

Keyword(s):

Escherichia Coli ◽

Bacterial Species ◽

Subclinical Mastitis ◽

Clinical Mastitis ◽

Economic Problem ◽

Cow Milk ◽

P Value ◽

Dairy Herds ◽

E Coli ◽

Bonferroni Test

Mastitis is a major economic problem in dairy herds, as it might decrease fertility, and negatively affect milk quality and milk yield. Out of over 150 bacterial species responsible for the udder inflammation, Escherichia coli is one of the most notable. This study aimed to assess antimicrobial susceptibility, resistance to dipping agents and biofilm formation of 150 E. coli strains isolated from milk of cows with subclinical and clinical mastitis. The strains came from three dairy herds located in Northern and Central Poland. The statistical analyses were performed with post-hoc Bonferroni test and chi-square test (including Yates correction). The data with a p value of <0.05 were considered significant. We found that the tested strains were mostly sensitive to antimicrobials and dipping agents. It was shown that 37.33% and 4.67% of strains were resistant and moderately resistant to at least one antimicrobial agent, respectively. No extended-spectrum beta-lactamases (ESBL)-producing E. coli were detected. The majority of strains did not possess the ability to form biofilm or formed a weak biofilm. The strong biofilm formers were found only among strains derived from cows with subclinical mastitis. The lowest bacteria number was noted for subclinical mastitis cows’ strains, after stabilization with iodine (3.77 log CFU × cm−2) and chlorhexidine (3.96 log CFU × cm−2) treatment. In the present study, no statistically significant differences in susceptibility to antibiotics and the ability to form biofilm were found among the strains isolated from cows with subclinical and clinical mastitis. Despite this, infections in dairy herds should be monitored. Limiting the spread of bacteria and characterizing the most common etiological factors would allow proper treatment.

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Toxicity of the First Ten MEIC Chemicals to Bacteria

Alternatives to Laboratory Animals ◽

10.1177/026119299302100205 ◽

1993 ◽

Vol 21 (2) ◽

pp. 151-155

Author(s):

Gustaw Kerszman

Keyword(s):

Escherichia Coli ◽

Bacillus Subtilis ◽

Linear Regression ◽

Minimal Inhibitory Concentration ◽

Blood Concentration ◽

Inhibitory Concentration ◽

Human Lymphocytes ◽

Bacterial Species ◽

E Coli ◽

Mild Toxicity

The toxicity of the first ten MEIC chemicals to Escherichia coli and Bacillus subtilis was examined. Nine of the chemicals were toxic to the bacteria, with the minimal inhibitory concentration (MIC) ranging from 10-3 to 4.4M. The sensitivities of both organisms were similar, but the effect on E. coli was often bactericidal, while it was bacteriostatic for B. subtilis. Digoxin was not detectably toxic to either bacterial species. Amitriptyline and FeSO4 were relatively less toxic to the bacteria than to human cells. For seven chemicals, a highly significant linear regression was established between log MIC in bacteria and log of blood concentration, giving lethal and moderate/mild toxicity in humans, as well as with toxicity to human lymphocytes.

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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

Journal of Food Protection ◽

10.4315/0362-028x-67.7.1377 ◽

2004 ◽

Vol 67 (7) ◽

pp. 1377-1383 ◽

Cited By ~ 13

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 < 0.001) their ORP values to <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 < 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 >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.

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Molecular types, virulence profiles and antimicrobial resistance of Escherichia coli causing bovine mastitis

Veterinary Record Open ◽

10.1136/vetreco-2019-000369 ◽

2019 ◽

Vol 6 (1) ◽

pp. e000369 ◽

Cited By ~ 5

Author(s):

Magdalena Nüesch-Inderbinen ◽

Nadine Käppeli ◽

Marina Morach ◽

Corinne Eicher ◽

Sabrina Corti ◽

...

Keyword(s):

Escherichia Coli ◽

Bovine Mastitis ◽

Tetracycline Resistance ◽

Diffusion Method ◽

Sample Population ◽

Disk Diffusion Method ◽

E Coli ◽

Phylogenetic Grouping ◽

Resistance Rates ◽

Susceptibility Profiles

BackgroundEscherichia coli is an important aetiological agent of bovine mastitis worldwide.MethodsIn this study, 82 E. coli from bovine mastitis milk samples from 49 farms were analysed for their genetic diversity using phylogenetic grouping and multilocus sequence typing. The isolates were examined by PCR for a selection of virulence factors (VFs). Antimicrobial susceptibility profiles were assessed using the disk diffusion method.ResultsThe most prevalent phylogroups were group B1 (41.5 per cent of the isolates) and group A (30.5 per cent). A variety of 35 different sequence types (STs) were identified, including ST1125 (11 per cent), ST58 (9.8 per cent), ST10 (8.5 per cent) and ST88 (7.3 per cent). Aggregate VF scores (the number of unique VFs detected for each isolate) ranged from 1 to 3 for 63.4 per cent of the isolates and were at least 4 for 12.2 per cent. For 24.4 per cent of the isolates, the score was 0. The three most frequent VFs were traT, fyuA and iutA. The majority (72 per cent) of the isolates harboured traT. The majority (68.3 per cent) of the isolates were fully susceptible to all antimicrobials tested, with 22 per cent resistant to ampicillin and 14.6 per cent to tetracycline. Resistance rates were low for gentamicin (3.7 per cent), amoxicillin/clavulanic acid (2.4 per cent) and ceftiofur (1.2 per cent), respectively.ConclusionAmong the study’s sample population, E. coli strains were genotypically diverse, even in cows from the same farm, although some STs occurred more frequently than others. Susceptibility to clinically relevant compounds remained high.

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Alteration of the phagocytosis and antimicrobial defense of Octodonta nipae (Coleoptera: Chrysomelidae) pupae to Escherichia coli following parasitism by Tetrastichus brontispae (Hymenoptera: Eulophidae)

Bulletin of Entomological Research ◽

10.1017/s0007485318000780 ◽

2018 ◽

Vol 109 (2) ◽

pp. 248-256

Author(s):

E. Meng ◽

J. Li ◽

B. Tang ◽

Y. Hu ◽

T. Qiao ◽

...

Keyword(s):

Escherichia Coli ◽

Immune Response ◽

Immune Responses ◽

Mrna Expression ◽

Bactericidal Activity ◽

Bacterial Infections ◽

Expression Level ◽

Primary Immune Response ◽

Mrna Expression Level ◽

E Coli

AbstractAlthough parasites and microbial pathogens are both detrimental to insects, little information is currently available on the mechanism involved in how parasitized hosts balance their immune responses to defend against microbial infections. We addressed this in the present study by comparing the immune response between unparasitized and parasitized pupae of the chrysomelid beetle, Octodonta nipae (Maulik), to Escherichia coli invasion. In an in vivo survival assay, a markedly reduced number of E. coli colony-forming units per microliter was detected in parasitized pupae at 12 and 24 h post-parasitism, together with decreased phagocytosis and enhanced bactericidal activity at 12 h post-parasitism. The effects that parasitism had on the mRNA expression level of selected antimicrobial peptides (AMPs) of O. nipae pupae showed that nearly all transcripts of AMPs examined were highly upregulated during the early and late parasitism stages except defensin 2B, whose mRNA expression level was downregulated at 24 h post-parasitism. Further elucidation on the main maternal fluids responsible for alteration of the primary immune response against E. coli showed that ovarian fluid increased phagocytosis at 48 h post-injection. These results indicated that the enhanced degradation of E. coli in parasitized pupae resulted mainly from the elevated bactericidal activity without observing the increased transcripts of target AMPs. This study contributes to a better understanding of the mechanisms involved in the immune responses of a parasitized host to bacterial infections.

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Involvement of the cgtA gene function in stimulation of DNA repair in Escherichia coli and Vibrio harveyi

Microbiology ◽

10.1099/mic.0.26292-0 ◽

2003 ◽

Vol 149 (7) ◽

pp. 1763-1770 ◽

Cited By ~ 12

Author(s):

Ryszard Zielke ◽

Aleksandra Sikora ◽

Rafał Dutkiewicz ◽

Grzegorz Wegrzyn ◽

Agata Czyż

Keyword(s):

Gene Expression ◽

Escherichia Coli ◽

Dna Repair ◽

Gene Product ◽

Uv Irradiation ◽

Vibrio Harveyi ◽

Bacterial Species ◽

Wild Type ◽

E Coli ◽

Stimulation Of

CgtA is a member of the Obg/Gtp1 subfamily of small GTP-binding proteins. CgtA homologues have been found in various prokaryotic and eukaryotic organisms, ranging from bacteria to humans. Nevertheless, despite the fact that cgtA is an essential gene in most bacterial species, its function in the regulation of cellular processes is largely unknown. Here it has been demonstrated that in two bacterial species, Escherichia coli and Vibrio harveyi, the cgtA gene product enhances survival of cells after UV irradiation. Expression of the cgtA gene was found to be enhanced after UV irradiation of both E. coli and V. harveyi. Moderate overexpression of cgtA resulted in higher UV resistance of E. coli wild-type and dnaQ strains, but not in uvrA, uvrB, umuC and recA mutant hosts. Overexpression of the E. coli recA gene in the V. harveyi cgtA mutant, which is very sensitive to UV light, restored the level of survival of UV-irradiated cells to the levels observed for wild-type bacteria. Moreover, the basal level of the RecA protein was lower in a temperature-sensitive cgtA mutant of E. coli than in the cgtA + strain, and contrary to wild-type bacteria, no significant increase in recA gene expression was observed after UV irradiation of this cgtA mutant. Finally, stimulation of uvrB gene transcription under these conditions was impaired in the V. harveyi cgtA mutant. All these results strongly suggest that the cgtA gene product is involved in DNA repair processes, most probably by stimulation of recA gene expression and resultant activation of RecA-dependent DNA repair pathways.

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1D TiO2 Nanostructures Prepared from Seeds Presenting Tailored TiO2 Crystalline Phases and Their Photocatalytic Activity for Escherichia coli in Water

International Journal of Photoenergy ◽

10.1155/2018/1862597 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Julieta Cabrera ◽

Dwight Acosta ◽

Alcides López ◽

Roberto J. Candal ◽

Claudia Marchi ◽

...

Keyword(s):

Escherichia Coli ◽

Photocatalytic Activity ◽

Bactericidal Activity ◽

Sol Gel ◽

Titanium Isopropoxide ◽

E Coli ◽

1D Nanostructures ◽

Sol Gel Synthesis ◽

Hydrolysis Of ◽

Tio2 Nanostructures

TiO2 nanotubes were synthesized by alkaline hydrothermal treatment of TiO2 nanoparticles with a controlled proportion of anatase and rutile. Tailoring of TiO2 phases was achieved by adjusting the pH and type of acid used in the hydrolysis of titanium isopropoxide (first step in the sol-gel synthesis). The anatase proportion in the precursor nanoparticles was in the 3–100% range. Tube-like nanostructures were obtained with an anatase percentage of 18 or higher while flake-like shapes were obtained when rutile was dominant in the seed. After annealing at 400°C for 2 h, a fraction of nanotubes was conserved in all the samples but, depending on the anatase/rutile ratio in the starting material, spherical and rod-shaped structures were also observed. The photocatalytic activity of 1D nanostructures was evaluated by measuring the deactivation of E. coli in stirred water in the dark and under UV-A/B irradiation. Results show that in addition to the bactericidal activity of TiO2 under UV-A illumination, under dark conditions, the decrease in bacteria viability is ascribed to mechanical stress due to stirring.

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Survey and Sequence Characterization of Bovine Mastitis-Associated Escherichia coli in Dairy Herds

Frontiers in Veterinary Science ◽

10.3389/fvets.2020.582297 ◽

2020 ◽

Vol 7 ◽

Author(s):

John I. Alawneh ◽

Ben Vezina ◽

Hena R. Ramay ◽

Hulayyil Al-Harbi ◽

Ameh S. James ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Bovine Mastitis ◽

Antibiotic Resistance Genes ◽

Tetracycline Resistance ◽

Sequence Type ◽

Genotypic Differences ◽

Beta Lactam ◽

Sequence Characterization ◽

E Coli

Escherichia coli is frequently associated with mastitis in cattle. “Pathogenic” and “commensal” isolates appear to be genetically similar. With a few exceptions, no notable genotypic differences have been found between commensal and mastitis-associated E. coli. In this study, 24 E. coli strains were isolated from dairy cows with clinical mastitis in three geographic regions of Australia (North Queensland, South Queensland, and Victoria), sequenced, then genomically surveyed. There was no observed relationship between sequence type (ST) and region (p = 0.51). The most common Multi Locus Sequence Type was ST10 (38%), then ST4429 (13%). Pangenomic analysis revealed a soft-core genome of 3,463 genes, including genes associated with antibiotic resistance, chemotaxis, motility, adhesion, biofilm formation, and pili. A total of 36 different plasmids were identified and generally found to have local distributions (p = 0.02). Only 2 plasmids contained antibiotic resistance genes, a p1303_5-like plasmid encoding multidrug-resistance (trimethoprim, quaternary ammonium, beta-lactam, streptomycin, sulfonamide, and kanamycin) from two North Queensland isolates on the same farm, while three Victorian isolates from the same farm contained a pCFSAN004177P_01-like plasmid encoding tetracycline-resistance. This pattern is consistent with a local spread of antibiotic resistance through plasmids of bovine mastitis cases. Notably, co-occurrence of plasmids containing virulence factors/antibiotic resistance with putative mobilization was rare, though the multidrug resistant p1303_5-like plasmid was predicted to be conjugative and is of some concern. This survey has provided greater understanding of antibiotic resistance within E. coli-associated bovine mastitis which will allow greater prediction and improved decision making in disease management.

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High Resolution Melt Assays to Detect and Identify Vibrio parahaemolyticus, Bacillus cereus, Escherichia coli, and Clostridioides difficile Bacteria

Microorganisms ◽

10.3390/microorganisms8040561 ◽

2020 ◽

Vol 8 (4) ◽

pp. 561

Author(s):

Allison C. Bender ◽

Jessica A. Faulkner ◽

Katherine Tulimieri ◽

Thomas H. Boise ◽

Kelly M. Elkins

Keyword(s):

Escherichia Coli ◽

High Resolution ◽

Bacillus Cereus ◽

Vibrio Parahaemolyticus ◽

Bacterial Species ◽

Human Pathogens ◽

High Resolution Melt ◽

E Coli ◽

Clostridioides Difficile ◽

Sensitivity Specificity

Over one hundred bacterial species have been determined to comprise the human microbiota in a healthy individual. Bacteria including Escherichia coli, Bacillus cereus, Clostridioides difficile, and Vibrio parahaemolyticus are found inside of the human body and B. cereus and E. coli are also found on the skin. These bacteria can act as human pathogens upon ingestion of contaminated food or water, if they enter an open wound, or antibiotics, and environment or stress can alter the microbiome. In this study, we present new polymerase chain reaction (PCR) high-resolution melt (HRM) assays to detect and identify the above microorganisms. Amplified DNA from C. difficile, E. coli, B. cereus, and V. parahaemolyticus melted at 80.37 ± 0.45 °C, 82.15 ± 0.37 °C, 84.43 ± 0.50 °C, and 86.74 ± 0.65 °C, respectively. A triplex PCR assay was developed to simultaneously detect and identify E. coli, B. cereus, and V. parahaemolyticus, and cultured microorganisms were successfully amplified, detected, and identified. The assays demonstrated sensitivity, specificity, reproducibility, and robustness in testing.

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Inactivation of Multi-Drug Resistant Non-Typhoidal Salmonella and Wild-Type Escherichia coli STEC Using Organic Acids: A Potential Alternative to the Food Industry

Pathogens ◽

10.3390/pathogens9100849 ◽

2020 ◽

Vol 9 (10) ◽

pp. 849

Author(s):

Vinicius Silva Castro ◽

Yhan da Silva Mutz ◽

Denes Kaic Alves Rosario ◽

Adelino Cunha-Neto ◽

Eduardo Eustáquio de Souza Figueiredo ◽

...

Keyword(s):

Escherichia Coli ◽

Acetic Acid ◽

Organic Acids ◽

Sodium Hypochlorite ◽

Bacterial Species ◽

Disk Diffusion ◽

Clinical Strains ◽

Linear Pattern ◽

E Coli ◽

Log Reduction

Salmonella and Escherichia coli are the main bacterial species involved in food outbreaks worldwide. Recent reports showed that chemical sanitizers commonly used to control these pathogens could induce antibiotic resistance. Therefore, this study aimed to describe the efficiency of chemical sanitizers and organic acids when inactivating wild and clinical strains of Salmonella and E. coli, targeting a 4-log reduction. To achieve this goal, three methods were applied. (i) Disk-diffusion challenge for organic acids. (ii) Determination of MIC for two acids (acetic and lactic), as well as two sanitizers (quaternary compound and sodium hypochlorite). (iii) The development of inactivation models from the previously defined concentrations. In disk-diffusion, the results indicated that wild strains have higher resistance potential when compared to clinical strains. Regarding the models, quaternary ammonium and lactic acid showed a linear pattern of inactivation, while sodium hypochlorite had a linear pattern with tail dispersion, and acetic acid has Weibull dispersion to E. coli. The concentration to 4-log reduction differed from Salmonella and E. coli in acetic acid and sodium hypochlorite. The use of organic acids is an alternative method for antimicrobial control. Our study indicates the levels of organic acids and sanitizers to be used in the inactivation of emerging foodborne pathogens.

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