Correction for Hasassri et al., An Immunocompromised Child with Bloodstream Infection Caused by Two Escherichia coli Strains, One Harboring NDM-5 and the Other Harboring OXA-48-Like Carbapenemase

We describe a 16-year-old neutropenic patient from the Middle East with bloodstream infection caused by two carbapenemase-producingEscherichia coliisolates that we characterized by whole-genome sequencing. While one displayed meropenem resistance and wasblaNDMpositive, the other demonstrated meropenem susceptibility yet harboredblaOXA181(which encodes ablaOXA48-like enzyme). This report highlights the challenge of laboratory detection ofblaOXA48-like enzymes and the clinical implications of genotypic resistance detection in carbapenemase-producingEnterobacteriaceae.

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Infection of Escherichia coli with bacteriophages

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063767 ◽

1969 ◽

Vol 27 ◽

pp. 370-371

Author(s):

Manfred E. Bayer

Keyword(s):

Escherichia Coli ◽

Nucleic Acid ◽

Cell Surface ◽

Virus Type ◽

Infection Process ◽

Adsorption Site ◽

The Other ◽

Specific Receptors ◽

Bacterial Receptors

The first step in the infection of a bacterium by a virus consists of a collision between cell and bacteriophage. The presence of virus-specific receptors on the cell surface will trigger a number of events leading eventually to release of the phage nucleic acid. The execution of the various "steps" in the infection process varies from one virus-type to the other, depending on the anatomy of the virus. Small viruses like ØX 174 and MS2 adsorb directly with their capsid to the bacterial receptors, while other phages possess attachment organelles of varying complexity. In bacteriophages T3 (Fig. 1) and T7 the small conical processes of their heads point toward the adsorption site; a welldefined baseplate is attached to the head of P22; heads without baseplates are not infective.

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The Nature of the Intramembrane Particle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003020 ◽

1980 ◽

Vol 38 ◽

pp. 688-691

Author(s):

A.J. Verkleij

Keyword(s):

Escherichia Coli ◽

Tight Junction ◽

Gap Junction ◽

The Other ◽

Fracture Face ◽

Band 3 Protein ◽

Satisfactory Explanation ◽

Freeze Fracturing ◽

Intramembrane Particle ◽

Luminal Membrane

Freeze-fracturing splits membranes into two helves, thus allowing an examination of the membrane interior. The 5-10 rm particles visible on both monolayers are widely assumed to be proteinaceous in nature. Most membranes do not reveal impressions complementary to particles on the opposite fracture face, if the membranes are fractured under conditions without etching. Even if it is considered that shadowing, contamination or fracturing itself might obscure complementary pits', there is no satisfactory explanation why under similar physical circimstances matching halves of other membranes can be visualized. A prominent example of uncomplementarity is found in the erythrocyte manbrane. It is wall established that band 3 protein and possibly glycophorin represents these nonccmplanentary particles. On the other hand a number of membrane types show pits opposite the particles. Scme well known examples are the ";gap junction',"; tight junction, the luminal membrane of the bladder epithelial cells and the outer membrane of Escherichia coli.

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Lac Operon Boolean Models: Dynamical Robustness and Alternative Improvements

Mathematics ◽

10.3390/math9060600 ◽

2021 ◽

Vol 9 (6) ◽

pp. 600 ◽

Cited By ~ 1

Author(s):

Marco Montalva-Medel ◽

Thomas Ledger ◽

Gonzalo A. Ruz ◽

Eric Goles

Keyword(s):

Escherichia Coli ◽

Limit Cycles ◽

The Other ◽

Lac Operon ◽

Boolean Models ◽

Bistable Behavior

In Veliz-Cuba and Stigler 2011, Boolean models were proposed for the lac operon in Escherichia coli capable of reproducing the operon being OFF, ON and bistable for three (low, medium and high) and two (low and high) parameters, representing the concentration ranges of lactose and glucose, respectively. Of these 6 possible combinations of parameters, 5 produce results that match with the biological experiments of Ozbudak et al., 2004. In the remaining one, the models predict the operon being OFF while biological experiments show a bistable behavior. In this paper, we first explore the robustness of two such models in the sense of how much its attractors change against any deterministic update schedule. We prove mathematically that, in cases where there is no bistability, all the dynamics in both models lack limit cycles while, when bistability appears, one model presents 30% of its dynamics with limit cycles while the other only 23%. Secondly, we propose two alternative improvements consisting of biologically supported modifications; one in which both models match with Ozbudak et al., 2004 in all 6 combinations of parameters and, the other one, where we increase the number of parameters to 9, matching in all these cases with the biological experiments of Ozbudak et al., 2004.

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A TTP-incorporated scoring model for predicting mortality of solid tumor patients with bloodstream infection caused by Escherichia coli

Supportive Care in Cancer ◽

10.1007/s00520-021-06442-z ◽

2021 ◽

Author(s):

Qing Zhang ◽

Hao-Yang Gao ◽

Ding Li ◽

Chang-Sen Bai ◽

Zheng Li ◽

...

Keyword(s):

Escherichia Coli ◽

High Risk ◽

Bloodstream Infection ◽

Solid Tumor ◽

Prognostic Scores ◽

Risk Scores ◽

Youden Index ◽

Tumor Patients ◽

Scoring Model ◽

Significant Difference

Abstract Background Few mortality-scoring models are available for solid tumor patients who are predisposed to develop Escherichia coli–caused bloodstream infection (ECBSI). We aimed to develop a mortality-scoring model by using information from blood culture time to positivity (TTP) and other clinical variables. Methods A cohort of solid tumor patients who were admitted to hospital with ECBSI and received empirical antimicrobial therapy was enrolled. Survivors and non-survivors were compared to identify the risk factors of in-hospital mortality. Univariable and multivariable regression analyses were adopted to identify the mortality-associated predictors. Risk scores were assigned by weighting the regression coefficients with corresponding natural logarithm of the odds ratio for each predictor. Results Solid tumor patients with ECBSI were distributed in the development and validation groups, respectively. Six mortality-associated predictors were identified and included in the scoring model: acute respiratory distress (ARDS), TTP ≤ 8 h, inappropriate antibiotic therapy, blood transfusion, fever ≥ 39 °C, and metastasis. Prognostic scores were categorized into three groups that predicted mortality: low risk (< 10% mortality, 0–1 points), medium risk (10–20% mortality, 2 points), and high risk (> 20% mortality, ≥ 3 points). The TTP-incorporated scoring model showed excellent discrimination and calibration for both groups, with AUC being 0.833 vs 0.844, respectively, and no significant difference in the Hosmer–Lemeshow test (6.709, P = 0.48) and the chi-square test (6.993, P = 0.46). Youden index showed the best cutoff value of ≥ 3 with 76.11% sensitivity and 79.29% specificity. TTP-incorporated scoring model had higher AUC than no TTP-incorporated model (0.837 vs 0.817, P < 0.01). Conclusions Our TTP-incorporated scoring model was associated with improving capability in predicting ECBSI-related mortality. It can be a practical tool for clinicians to identify and manage bacteremic solid tumor patients with high risk of mortality.

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Escherichia coli O157:H7 SURVIVAL IN TRADITIONAL AND LOW LACTOSE YOGURT DURING FERMENTATION AND COOLING PERIODS

Ciência Animal Brasileira ◽

10.1590/1089-6891v18e-39554 ◽

2017 ◽

Vol 18 (0) ◽

Author(s):

Camila Sampaio Cutrim ◽

Raphael Ferreira de Barros ◽

Robson Maia Franco ◽

Marco Antonio Sloboda Cortez

Keyword(s):

Escherichia Coli ◽

The Other ◽

Lactose Hydrolysis ◽

Escherichia Coli O157 ◽

E Coli ◽

Gas Formation ◽

Whole Milk ◽

Milk Contamination ◽

Different Types ◽

Fermentation Period

Abstract The purpose of this study was to evaluate the behavior of E. coli O157:H7 during lactose hydrolysis and fermentation of traditional and low lactose yogurt. It also aimed to verify E. coli O157:H7 survival after 12 h of storage at 4 ºC ±1 ºC. Two different types of yogurts were prepared, two with whole milk and two with pre-hydrolyzed whole milk; in both groups one yogurt was inoculated with E. coli O157:H7 and the other one was not inoculated. The survival of E. coli and pH of yogurt were determined during fermentation and after 12-h refrigeration. The results showed that E. coli O157:H7 was able to grow during the fermentation period (from 4.34 log CFU.mL-1 to 6.13 log CFU.mL-1 in traditional yogurt and 4.34 log CFU.mL-1 to 6.16 log CFU.mL-1 in low lactose yogurt). The samples with E. coli O157:H7 showed gas formation and syneresis. Thus, E. coli O157:H7 was able to survive and grow during fermentation of traditional and low lactose yogurts affecting the manufacture technology. Moreover, milk contamination by E. coli before LAB addition reduces the growth of L. bulgaricus and S. thermophilus especially when associated with reduction of lactose content.

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Characterization of the Two Mycobacterium tuberculosis recA Promoters

Journal of Bacteriology ◽

10.1128/jb.185.20.6005-6015.2003 ◽

2003 ◽

Vol 185 (20) ◽

pp. 6005-6015 ◽

Cited By ~ 21

Author(s):

Krishna K. Gopaul ◽

Patricia C. Brooks ◽

Jean-François Prost ◽

Elaine O. Davis

Keyword(s):

Escherichia Coli ◽

Dna Damage ◽

Mycobacterium Tuberculosis ◽

Promoter Activity ◽

The Other ◽

Expression Level ◽

Promoter Elements ◽

Kinetics Of

ABSTRACT The recA gene of Mycobacterium tuberculosis is unusual in that it is expressed from two promoters, one of which, P1, is DNA damage inducible independently of LexA and RecA, while the other, P2, is regulated by LexA in the classical way (E. O. Davis, B. Springer, K. K. Gopaul, K. G. Papavinasasundaram, P. Sander, and E. C. Böttger, Mol. Microbiol. 46:791-800, 2002). In this study we characterized these two promoters in more detail. Firstly, we localized the promoter elements for each of the promoters, and in so doing we identified a mutation in each promoter which eliminates promoter activity. Interestingly, a motif with similarity to Escherichia coli σ70 −35 elements but located much closer to the −10 element is important for optimal expression of P1, whereas the sequence at the −35 location is not. Secondly, we found that the sequences flanking the promoters can have a profound effect on the expression level directed by each of the promoters. Finally, we examined the contribution of each of the promoters to recA expression and compared their kinetics of induction following DNA damage.

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Cooperative Roles of Nitric Oxide-Metabolizing Enzymes To Counteract Nitrosative Stress in Enterohemorrhagic Escherichia coli

Infection and Immunity ◽

10.1128/iai.00334-19 ◽

2019 ◽

Vol 87 (9) ◽

Cited By ~ 1

Author(s):

Takeshi Shimizu ◽

Akio Matsumoto ◽

Masatoshi Noda

Keyword(s):

Nitric Oxide ◽

Escherichia Coli ◽

Stationary Phase ◽

Nitrosative Stress ◽

Enterohemorrhagic Escherichia Coli ◽

The Other ◽

Anaerobic Growth ◽

Bacterial Cells ◽

Metabolizing Enzymes ◽

Microaerobic Conditions

ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) has at least three enzymes, NorV, Hmp, and Hcp, that act independently to lower the toxicity of nitric oxide (NO), a potent antimicrobial molecule. This study aimed to reveal the cooperative roles of these defensive enzymes in EHEC against nitrosative stress. Under anaerobic conditions, combined deletion of all three enzymes significantly increased the NO sensitivity of EHEC determined by the growth at late stationary phase; however, the expression of norV restored the NO resistance of EHEC. On the other hand, the growth of Δhmp mutant EHEC was inhibited after early stationary phase, indicating that NorV and Hmp play a cooperative role in anaerobic growth. Under microaerobic conditions, the growth of Δhmp mutant EHEC was inhibited by NO, indicating that Hmp is the enzyme that protects cells from NO stress under microaerobic conditions. When EHEC cells were exposed to a lower concentration of NO, the NO level in bacterial cells of Δhcp mutant EHEC was higher than those of the other EHEC mutants, suggesting that Hcp is effective at regulating NO levels only at a low concentration. These findings of a low level of NO in bacterial cells with hcp indicate that the NO consumption activity of Hcp was suppressed by Hmp at a low range of NO concentrations. Taken together, these results show that the cooperative effects of NO-metabolizing enzymes are regulated by the range of NO concentrations to which the EHEC cells are exposed.

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Associated factors and clinical outcomes of bloodstream infection due to extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae during febrile neutropenia

International Journal of Antimicrobial Agents ◽

10.1016/j.ijantimicag.2018.12.003 ◽

2019 ◽

Vol 53 (4) ◽

pp. 423-428 ◽

Cited By ~ 5

Author(s):

Eli Ben-Chetrit ◽

Mustafa Abed Eldaim ◽

Maskit Bar-Meir ◽

Mutaz Dodin ◽

David E. Katz

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Febrile Neutropenia ◽

Bloodstream Infection ◽

Clinical Outcomes ◽

Associated Factors ◽

Extended Spectrum

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Research on reproductive performance of mares in Serbia using bacteriological examination

Biotechnology in Animal Husbandry ◽

10.2298/bah1103883u ◽

2011 ◽

Vol 27 (3) ◽

pp. 883-892

Author(s):

M.I. Urosevic ◽

D. Stojanovic ◽

B. Lako ◽

I. Jajic ◽

Z. Milicic ◽

...

Keyword(s):

Escherichia Coli ◽

Reproductive Performance ◽

Staphylococcus Epidermidis ◽

Pasteurella Multocida ◽

Bacterial Species ◽

The Other ◽

Streptococcus Zooepidemicus ◽

Bacteriological Examination ◽

Reproductive Disorders ◽

Bacillus Spp

The research was conducted on 19 stud farms in Serbia, on 80 mares used for breeding, with and without reproductive disorders. During the two years period (from 2009 to 2010) double guarded uterine swabs from 80 mares, aged between 3 and 22 years were collected. Mares belonged to the different breeds: Thoroughbred, Standardbred, Lipizzaner and mixed breeds. It was determined, that bacterial infection of genital organs was found in 24 mares in the examined population, and the bacterial species Streptococcus zooepidemicus was diagnosed in the 11 samples from cervical swabs. In the 5 samples, Escherichia coli was isolated, while Staphylococcus epidermidis and Pasteurella multocida were present in the 2 samples each, while the other causes and simultaneous isolation of two bacterial species are much less present. These species are: Bacillus spp. plus Escherichia coli; Streptococcus zooepidemicus plus Klebsiella pneumoniae and Escherichia coli plus Streptococcus zooepidemicus. In one swab we determinated Arcanobacter pyogenes. In this examination, according to available data after natural mating, we found conception level of 43,10%, which is similar with previous reports in our country.

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