scholarly journals A Family of Stability Determinants in Pathogenic Bacteria

1998 ◽  
Vol 180 (23) ◽  
pp. 6415-6418 ◽  
Author(s):  
Finbarr Hayes
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Haemophilus Influenzae ◽  
Vibrio Cholerae ◽  
Pathogenic Bacteria ◽  
Plasmid Stability ◽  
Overlapping Genes ◽  
Morganella Morganii ◽  
E Coli ◽  
Segregational Stability

ABSTRACT A novel segregational stability system was identified on plasmid R485, which originates from Morganella morganii. The system is composed of two overlapping genes, stbD andstbE, which potentially encode proteins of 83 and 93 amino acids, respectively. Homologs of the stbDE genes were identified on the enterotoxigenic plasmid P307 from Escherichia coli and on the chromosomes of Vibrio cholerae andHaemophilus influenzae biogroup aegyptius. The former two homologs also promote plasmid stability in E. coli. Furthermore, the stbDE genes share homology with components of the relBEF operon and with thednaT gene of E. coli. The organization of thestbDE cassette is reminiscent of toxin-antitoxin stability cassettes.

scholarly journals Abundance of pathogenic Escherichia coli, Salmonella typhimurium and Vibrio cholerae in Nkonkobe drinking water sources

2006 ◽  
Vol 4 (3) ◽  
pp. 289-296 ◽  
Author(s):  
Maggy N. B. Momba ◽  
Veronica K. Malakate ◽  
Jacques Theron
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Salmonella Typhimurium ◽  
Vibrio Cholerae ◽  
Water Samples ◽  
Pathogenic Bacteria ◽  
Culture Media ◽  
Water Sources ◽  
E Coli ◽  
Drinking Water Sources

In order to study the prevalence of enteric pathogens capable of causing infection and disease in the rural communities of Nkonkobe, bacterial isolates were collected from several surface water and groundwater sources used by the community for their daily water needs. By making use of selective culture media and the 20E API kit, presumptive Escherichia coli, Salmonella spp. and Vibrio cholerae isolates were obtained and then analysed by polymerase chain reaction assays (PCR). The PCR successfully amplified from water samples a fragment of E. coli uidA gene that codes for β-D-glucuronidase which is a highly specific characteristic of enteropathogenic E. coli, enterotoxigenic E. coli and entero-invasive E. coli. The PCR also amplified the epsM gene from water samples containing toxigenic V. cholerae. Although E. coli was mostly detected in groundwater sources, toxigenic V. cholerae was detected in both surface and groundwater sources. There was a possibility of Salmonella typhimurium in Ngqele and Dyamala borehole water samples. The presence of these pathogenic bacteria in the above drinking water sources may pose a serious health risk to consumers.

Effect of microalgae growing on wastewater batch culture on escherichia coli and vibrio cholerae survival

1994 ◽  
Vol 30 (8) ◽  
pp. 295-302 ◽  
Author(s):  
N. Mezrioui ◽  
B. Oudra ◽  
K. Oufdou ◽  
L. Hassani ◽  
M. Loudiki ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Batch Culture ◽  
Pathogenic Bacteria ◽  
Bacterial Load ◽  
Treated Wastewater ◽  
Coliform Bacteria ◽  
Organic Load ◽  
E Coli ◽  
Stabilization Ponds

The stabilization pond is one of the more important biological wastewater treatment systems, applied in many countries. An experiment treating wastewater by stabilization ponds under the arid climate of Marrakesh (Morocco) has been underway since 1985. The experimental installation, made from two lined stabilization ponds, received domestic sewage which carried not only the organic load but also a significant bacterial load and other microorganisms. In this new habitat, the cells' bacterial behaviour was affected by various physico-chemical and biological factors. It appears that in such treatment system, known for excessive algal production, the microalgae has evidently an influence on bacterial growth. In this paper, we proposed to appreciate how microalgae essentially: Chlorella (Chlorophyta), Synechococcus andSynechocystis (Cyanobacteria), can affect the behaviour, survival and temporal evolution of Escherichia coli and Vibrio cholerae. In wastewater stabilization ponds of Marrakesh high levels of V. cholerae and low concentrations of coliform bacteria were noted during summer periods. This period coincided with a bloom of picocyanobacteria associated with a weak relative abundance of Chlorella. Some interactions tests were carried out with these bacteria and these algae, using a treated wastewater batch culture. Results show that the green algae reduces V. cholerae (pathogenic bacteria) abundances more than E. coli (fecal contamination bacteria) where as better survival of this pathogenic bacteria was noted in presence of Cyanobacteria. The die-off of E. coli appears to be more reduced in presence of Cyanobacteria than Chlorella. Furthermore, the alkaline pH seems to present a more bactericidal effect on E. coli than on V. cholerae. Thus, the Cyanobacteria blooms, associated with a weak percentage of Chlorella abundance, occurring periodically during summer in sewage stabilization ponds of Marrakesh, will be considered as one of the major factors leading to high levels of V. cholerae and low abundances of fecal coliform bacteria during the hot period.

scholarly journals Development of Molecular Rapid Detection for Vibrio cholerae and Escherichia coli

2020 ◽  
Author(s):  
Diana Elizabeth Waturangi ◽  
JASON PETRUS ◽  
RICO KOSASIH ◽  
GLORIA RAISSA
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
False Positive ◽  
Rapid Detection ◽  
Pathogenic Bacteria ◽  
Molecular Detection ◽  
Detection Method ◽  
False Negative ◽  
E Coli ◽  
Drinking Water Samples

Abstract Background: Vibrio cholerae and Escherichia coli were main causative agent foodborne diseases, especially in many developing countries, such as Indonesia. Thereby, rapid detection of these pathogenic bacteria is necessary to quickly detect infection that occurred so it can be treated immediately. In this case, multiplex PCR allows multiple genes amplification in one reaction thereby enable to perform rapid detection of these pathogenic bacteria. The objective of this study is to develop rapid molecular detection of V. Cholerae and E. coli and analyze the sensitivity and specificity of this assay.Result: In this study, we used various virulence genes in each pathogenic bacteria as marker to develop rapid molecular detection. Based on this research, optimum results of V. cholerae and E. coli rapid detection were obtained with a primer concentration of 16 µM for ctxA and ompU, 30 µM for ace, and 50 µM for zot, and toxR; 2 µM for elt and 5 µM for stx, respectively. Finally, based on the method standardization by ISO/TS 20836 these assays had 0% false positive, 0% false negative, 100% specificity, and 100% sensitivity; 0% false positive, 4% false negative, 100% specificity, and 96% sensitivity for V. cholerae and E. coli respectively. Conclusion: The optimized method was qualified to be used as a detection method for V. cholerae and E. coli detection according to ISO/TS 20836 (2017) and EHEC and ETEC contamination in drinking water samples.

scholarly journals Development of a Set of Primers for Drug-Resistance Genes Detection in the Agents of Dangerous Bacterial Infections as Exemplified by Yersinia pestis, Vibrio cholerae, Escherichia coli Strains

2014 ◽  
pp. 57-60 ◽  
Author(s):  
K. A. Nikiforov ◽  
L. V. Anisimova ◽  
G. N. Odinokov ◽  
A. V. Fadeeva ◽  
L. A. Novichkova ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Drug Resistance ◽  
Yersinia Pestis ◽  
Vibrio Cholerae ◽  
Resistance Genes ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
E Coli ◽  
Genes Encoding ◽  
Drug Resistant Strains

A set of primers for detection of genes encoding resistance to streptomycin ( strA, strB ), tetracyclin ( tetA, tetR ), chloramphenicol ( catА ), kanamycin ( npt , aphA ), vankomycin ( sanA ), polymyxin ( pmrD ) has been developed with the aim of rapid and effective detection of drug-resistant strains of dangerous bacterial infections agents. Efficacy of constructed primers has been confirmed against a panel of 40 Yersinia pestis, 49 Vibrio cholerae, and 2 Escherichia coli strains from the State collection of pathogenic bacteria of the RAPI “Microbe”. Drug-resistance genes ntp and catA have been detected in plague agent strains , strA, strB , npt , aphA , tetA and tetR - in cholera agent; strA , tetR , ntp and aphA - in pathogenic strain E. coli О157:H7. Determined is universal character of the designed primers for drug-resistance genes detection in these pathogenic bacteria species.

scholarly journals OPTIMIZATION OF MOLECULAR DETECTION FOR Vibrio cholerae and PATHOGENIC Escherichia coli USING MULTIPLEX PCR

2021 ◽  
pp. e299
Author(s):  
Diana Elizabeth Waturangi ◽  
Jason Petrus ◽  
Rico Kosasih ◽  
Felicia Roseline
Keyword(s):  
Escherichia Coli ◽  
Multiplex Pcr ◽  
Vibrio Cholerae ◽  
False Positive ◽  
Rapid Detection ◽  
Pathogenic Bacteria ◽  
Molecular Detection ◽  
False Negative ◽  
E Coli ◽  
Pathogenic Escherichia Coli

Vibrio cholerae and pathogenic Escherichia coli were considered as main causative agent foodborne diseases especially in many developing countries, such as Indonesia. Thereby, rapid detection of these pathogenic bacteria is necessary to treat food-borne related diseases causing by these bacteria. In this case, multiplex PCR allows multiple genes amplification in one reaction thereby enable to perform rapid detection of these pathogenic bacteria. The objective of this study is to optimize uniplex and multiples PCR of V. cholerae and pathogenic E. coli detection and determine the sensitivity and specificity of this assays. We used various virulence genes for each pathogenic bacterium as markers for uniplex and multiplex PCR detection. Based on this research, the optimum results of V. cholerae and pathogenic E. coli were obtained with a primer concentration of 16 µM for ctxA and ompU, 30 µM for ace, and 50 µM for zot, and toxR; 2 µM for elt and 5 µM for stx, respectively. Finally, based on the standardization method by ISO/TS 20836 these assays had 0% false positive, 0% false negative, 100% specificity, and 100% sensitivity; 0% false positive, 4% false negative, 100% specificity, and 96% sensitivity for V. cholerae and pathogenic E. coli respectively. The optimized method was qualified to be used as a molecular detection for V. cholerae as well as EHEC and ETEC detection according to ISO/TS 20836 (2017)  from drinking water samples.

scholarly journals Roles of the C-Terminal Amino Acids of Non-Hexameric Helicases: Insights from Escherichia coli UvrD

2021 ◽  
Vol 22 (3) ◽  
pp. 1018
Author(s):  
Hiroaki Yokota
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Single Molecule ◽  
Underlying Mechanism ◽  
Amino Acid Sequences ◽  
E Coli ◽  
X Ray Crystallography ◽  
Terminal Amino

Helicases are nucleic acid-unwinding enzymes that are involved in the maintenance of genome integrity. Several parts of the amino acid sequences of helicases are very similar, and these quite well-conserved amino acid sequences are termed “helicase motifs”. Previous studies by X-ray crystallography and single-molecule measurements have suggested a common underlying mechanism for their function. These studies indicate the role of the helicase motifs in unwinding nucleic acids. In contrast, the sequence and length of the C-terminal amino acids of helicases are highly variable. In this paper, I review past and recent studies that proposed helicase mechanisms and studies that investigated the roles of the C-terminal amino acids on helicase and dimerization activities, primarily on the non-hexermeric Escherichia coli (E. coli) UvrD helicase. Then, I center on my recent study of single-molecule direct visualization of a UvrD mutant lacking the C-terminal 40 amino acids (UvrDΔ40C) used in studies proposing the monomer helicase model. The study demonstrated that multiple UvrDΔ40C molecules jointly participated in DNA unwinding, presumably by forming an oligomer. Thus, the single-molecule observation addressed how the C-terminal amino acids affect the number of helicases bound to DNA, oligomerization, and unwinding activity, which can be applied to other helicases.

scholarly journals High-density transposon libraries utilising outward-oriented promoters identify mechanisms of action and resistance to antimicrobials

2020 ◽  
Vol 367 (22) ◽  
Author(s):  
Chris Coward ◽  
Gopujara Dharmalingham ◽  
Omar Abdulle ◽  
Tim Avis ◽  
Stephan Beisken ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Pathogenic Bacteria ◽  
Selective Advantage ◽  
Mechanisms Of Action ◽  
Over Expression ◽  
E Coli ◽  
Synthase Inhibitor ◽  
Established Technique ◽  
Bacterial Transposon

ABSTRACT The use of bacterial transposon mutant libraries in phenotypic screens is a well-established technique for determining which genes are essential or advantageous for growth in conditions of interest. Standard, inactivating, transposon libraries cannot give direct information about genes whose over-expression gives a selective advantage. We report the development of a system wherein outward-oriented promoters are included in mini-transposons, generation of transposon mutant libraries in Escherichia coli and Pseudomonas aeruginosa and their use to probe genes important for growth under selection with the antimicrobial fosfomycin, and a recently-developed leucyl-tRNA synthase inhibitor. In addition to the identification of known mechanisms of action and resistance, we identify the carbon–phosphorous lyase complex as a potential resistance liability for fosfomycin in E. coli and P. aeruginosa. The use of this technology can facilitate the development of novel mechanism-of-action antimicrobials that are urgently required to combat the increasing threat worldwide from antimicrobial-resistant pathogenic bacteria.

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.

PCR for the Specific Detection of an Escherichia coli O157:H7 Laboratory Control Strain

2015 ◽  
Vol 78 (9) ◽  
pp. 1738-1744 ◽  
Author(s):  
MICHAEL KNOWLES ◽  
DOMINIC LAMBERT ◽  
GEORGE HUSZCZYNSKI ◽  
MARTINE GAUTHIER ◽  
BURTON W. BLAIS
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Control Measure ◽  
Positive Control ◽  
Food Microbiology ◽  
Escherichia Coli O157 ◽  
Control Strain ◽  
E Coli ◽  
Signature Sequences ◽  
Materials Used

Control strains of bacterial pathogens such as Escherichia coli O157:H7 are commonly processed in parallel with test samples in food microbiology laboratories as a quality control measure to assure the satisfactory performance of materials used in the analytical procedure. Before positive findings can be reported for risk management purposes, analysts must have a means of verifying that pathogenic bacteria (e.g., E. coli O157:H7) recovered from test samples are not due to inadvertent contamination with the control strain routinely handled in the laboratory environment. Here, we report on the application of an in-house bioinformatic pipeline for the identification of unique genomic signature sequences in the development of specific oligonucleotide primers enabling the identification of a common positive control strain, E. coli O157:H7 (ATCC 35150), using a simple PCR procedure.

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