scholarly journals The viable but non-culturable state in pathogenic Escherichia coli: A general review

2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Jennifer A. Pienaar ◽  
Atheesha Singh ◽  
Tobias G. Barnard
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Health Impact ◽  
Stress Factors ◽  
Detection Methods ◽  
Vbnc State ◽  
E Coli ◽  
Escherichia Coli Bacteria ◽  
General Aspects

Background: The persistence and pathogenicity of pathogenic bacteria are dependent on the ability of the species to survive in adverse conditions. During the infectious process, the organism may need to pass through certain hostile anatomical sites, such as the stomach. Under various environmental stresses, many bacteria enter into the viable but non-culturable (VBNC) state, where they are ‘alive’ or metabolically active, but will not grow on conventional media. Escherichia coli bacteria encounter several diverse stress factors during their growth, survival and infection and thus may enter into the VBNC state.Objectives: This review discusses various general aspects of the VBNC state, the mechanisms and possible public health impact of indicator and pathogenic E. coli entering into the VBNC state.Method: A literature review was conducted to ascertain the possibleimpact of E. coli entering into the VBNC state.Results: Escherichia coli enter into the VBNC state by means of several induction mechanisms. Various authors have found that E. coli can be resuscitated post-VBNC. Certain strains of pathogenic E. coli are still able to produce toxins in the VBNC state, whilst others are avirulent during the VBNC state but are able to regain virulence after resuscitation.Conclusion: Pathogenic and indicator E. coli entering into the VBNC state could have an adverse effect on public health if conventional detection methods are used, where the number of viable cells could be underestimated and the VBNC cells still produce toxins or could, at anytime, be resuscitated and become virulent again.

scholarly journals UJI AKTIVITAS ANTIBAKTERI EKSTRAK DAN FRAKSI SPONS Leucetta chagosensis DARI PERAIRAN PULAU MANTEHAGE SULAWESI UTARA TERHADAP PERTUMBUHAN BAKTERI Staphylococcus aureus DAN Escherichia coli

PHARMACON ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 834
Author(s):  
Eunike Pelealu ◽  
Defny S. Wewengkang ◽  
Surya Sumantri Abdullah
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacterial Growth ◽  
Pathogenic Bacteria ◽  
Inhibition Zone ◽  
Disk Diffusion ◽  
E Coli ◽  
Activity Test ◽  
Escherichia Coli Bacteria ◽  
Metabolite Content

ABSTRACTSponges are one of the biota components that make up coral reefs which are quite widely distributed. The metabolite content in the sponge can ward off and inhibit the pathogenic bacteria that interfere with it. This study aims to determine the activity of inhibiting bacterial growth from the extract and fraction of Leucetta chagosensis sponge against the growth of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. The samples were extracted using the maceration method with 95% ethanol solvent and then fractionated using 3 solvents with different polarity levels, namely methanol, n-hexane and chloroform. Activity test using the disk diffusion agar method of Kirby and Bauer. Only the MeOH fraction was able to inhibit the growth of E. coli bacteria with an average inhibition zone of 6.88 mm. Whereas for S.aureus bacteria extracts and all fractions showed activity to inhibit bacterial growth with an average inhibition zone of EtOH (6.61 mm), CHCI3 (6.68 mm), n-hexane (7.83 mm) and MeOH (8.00 mm), respectively. All activities that are shown are categorized as weak (weak).Keywords: Antibacterial, Leucetta chagosensis, Staphylococcus aureus, Escherichia coli ABSTRAKSpons merupakan salah satu komponen biota penyusun terumbu karang yang penyebarannya cukup luas. Kandungan metabolit yang ada di dalam spons dapat menangkal dan menghambat bakteri patogen pengganggunya.  Penelitian ini bertujuan untuk melihat aktivitas menghambat pertumbuhan bakteri dari ekstrak dan fraksi spons Leucetta chagosensis. terhadap pertumbuhan bakteri Gram positif Staphylococcus aureus dan Gram negatif Escherichia coli. Sampel di ekstraksi menggunakan metode maserasi dengan pelarut etanol 95% lalu di fraksinasi dengan menggunakan 3 pelarut dengan tingkat kepolaran yang berbeda yaitu metanol, n-heksan dan kloroform. Uji aktivitas menggunakan metode disk diffusion agar Kirby dan Bauer.  Hanya fraksi MeOH yang mampu menghambat pertumbuhan bakteri E.coli dengan zona hambat rata-rata 6,88 mm. Sedangkan terhadap bakteri S.aureus ekstrak dan semua fraksi menunjukan aktifitas menghambat pertumbuhan bakteri dengan rata-rata zona hambat masing-masing EtOH (6,61 mm), CHCl3 (6,68 mm), n-Heksan (7,83 mm), dan MeOH (8,00 mm). Semua aktivitas yang ditunjukan dikategorikan lemah (weak).Kata kunci : Antibakteri, Leucetta chagosensis, Staphylococcus aureus,  Escherichia coli

scholarly journals Transcriptomic Analysis of Viable but Non-Culturable Escherichia coli O157:H7 Formation Induced by Low Temperature

2019 ◽  
Vol 7 (12) ◽  
pp. 634 ◽  
Author(s):  
Junliang Zhong ◽  
Xihong Zhao
Keyword(s):  
Escherichia Coli ◽  
Low Temperature ◽  
Differentially Expressed Genes ◽  
Pathogenic Bacteria ◽  
Differentially Expressed ◽  
Transmembrane Transport ◽  
Pathway Enrichment Analysis ◽  
Escherichia Coli O157 ◽  
Vbnc State ◽  
E Coli

Escherichia coli O157:H7 is one of the most common pathogenic bacteria that pose a threat to food safety. The aim of this study was to investigate the mechanisms of the formation of viable but non-culturable (VBNC) E. coli O157:H7 induced by low temperature (−20 °C) using RNA sequencing (RNA-Seq) transcriptomics analysis. The results of the present investigation revealed the presence of 2298 differentially expressed genes in VBNC cells, accounting for 46.03% of the total number of genes. Additionally, GO function and KEGG pathway enrichment analysis were performed to investigate the functional and related metabolic pathways of the differentially expressed genes. We found that the ion transport, protein synthesis, and protein transmembrane transport activities were significantly improved in the VBNC cells, indicating that E. coli O157:H7 cells synthesized a considerable amount of protein to maintain the levels of their functional metabolic processes and life activities in the VBNC state. In conclusion, we suggest that the increased synthesis of proteins such as SecY, FtsY, and Ffh might indicate that they are the key proteins involved in the improvement of the transmembrane transport activities in VBNC E. coli O157:H7 cells, maintaining their functional metabolism in the VBNC state and enhancing their survival ability under low temperatures.

The Association between Food Hygiene and the Escherichia Coli Contamination on School Snack at Elementary School in Cakung Subdistrict, East Jakarta

2020 ◽  
Author(s):  
Hanifatun Nisa Ath Thoriqoh ◽  
◽  
Budi Haryanto ◽  
Ela Laelasari ◽  
◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Disease Transmission ◽  
Pathogenic Bacteria ◽  
Cluster Sampling ◽  
Food Hygiene ◽  
Study Program ◽  
Cross Sectional ◽  
E Coli ◽  
Cooked Food

Background: Unsafe food hygiene poses threats for becoming disease transmission. The most common of foodborne pathogenic bacteria is Escherichia coli. The purpose of this study was to examine the association between food hygiene and the contamination of escherichia coli bacteria on school snack. Subejcts and Method: A cross-sectional study was conducted in Cakung, East Jakarta from December 2016 to January 2017. A sample of 60 food handlers from a total of 147 foods handlers’ population was selected by cluster sampling. The dependent variable was E. coli bateria. The independent variables were proper hand washing, food serving aids, proper equipment washing, types of selling facilities, sanitation facilities, the placement of cooked food, and food preparation. The data were collected by laboratory test result and questionnaire. The data were analyzed by multiple logistic regressions. Results: As many as 45% of the positive snacks were contaminated with E. coli bacteria. E. coli bacterial contamination on food was related to the practice of using food serving aids (OR= 5.00; 95% CI= 1.19 to 20.92; p= 0.044), a place to store cooked food (OR= 6.11; 95% CI = 1.73 to 21.59; p = 0.007) and method of presentation (OR = 7.14; 95% CI = 1.43 to 35.57; p = 0.002). Conclusion: The incidence of Escherichia coli contamination on food is related to the practice of using food serving aids, the placement of cooked food and food serving. Keywords: Escherichia coli, school snack Corresponden: Hanifatun Nisa Ath Thoriqoh. Public Health Postgraduate Study Program, Faculty of Public Health, University of Indonesia, Depok, West Java. Email: [email protected]. Mobile: 081808157745. DOI: https://doi.org/10.26911/the7thicph.02.13

Incidence of Salmonella, Listeria monocytogenes, Escherichia coli O157:H7, and Staphylococcal Enterotoxin in Two Types of Mexican Fresh Cheeses

2012 ◽  
Vol 75 (1) ◽  
pp. 79-84 ◽  
Author(s):  
M. R. TORRES-VITELA ◽  
M. MENDOZA-BERNARDO ◽  
J. CASTRO-ROSAS ◽  
C. A. GOMEZ-ALDAPA ◽  
L. E. GARAY-MARTINEZ ◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Health Risk ◽  
Pathogenic Bacteria ◽  
Culture Method ◽  
Staphylococcal Enterotoxin ◽  
Escherichia Coli O157 ◽  
Milk Product ◽  
Public Health Risk ◽  
E Coli

Handcrafted fresh cheeses are popular among consumers in Mexico. However, unsafe raw materials and inadequate food safety practices during cheese manufacture and preservation make them a potential public health risk. The incidence of Salmonella, Listeria, Escherichia coli O157:H7, and staphylococcal enterotoxin was analyzed in two types of fresh cheese (panela and adobera) commonly marketed in Mexico. A total of 200 samples, 100 panela and 100 adobera, were acquired from 100 wholesale milk product distributors who supply small retailers in the Guadalajara metropolitan area, Jalisco State, Mexico. Pathogens were identified using culture and immunoassay (miniVidas) methods. The presence of staphylococcal enterotoxin was determined by an immunoassay method. Of the 200 analyzed samples, 92 were positive for at least one of the pathogens. The incidence in the panela samples was 56%: 34% Salmonella, 16% E. coli O157:H7, and 6% L. monocytogenes. In the adobera samples, incidence was 36%: 20% Salmonella, 4% E. coli O157:H7, and 12% L. monocytogenes. Staphylococcal enterotoxin was not detected in any of the 200 samples. Choice of technique had no effect on detection of pathogen incidence, although the immunoassay method identified more Salmonella serotypes than the culture method. Handcrafted panela and adobera fresh cheeses in Mexico frequently contain pathogenic bacteria and therefore pose a public health risk.

scholarly journals UJI EFEK ANTIBAKTERI JAMUR ENDOFIT PADA TUMBUHAN SEREH (Cymbopogon citratus) PADA BAKTERI UJI Staphylococcus aureus DAN Escherichia coli

PHARMACON ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 705
Author(s):  
Fathia Falugah ◽  
Jimmy Posangi ◽  
Paulina V. Y. Yamlean
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Endophytic Fungi ◽  
Pathogenic Bacteria ◽  
Antibacterial Effect ◽  
Cymbopogon Citratus ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Escherichia Coli Bacteria

ABSTRACT Endophytic fungi are fungi that live in plant tissues and do not harm these plants. Endophytic fungi can produce compounds that have the potential as antibacterial. This study aimed to examine the antibacterial effects of endophytic fungi isolated from the lemongrass (Cymbopogon citratus) against Staphylococcus aureus and Escherichia coli bacteria. Lemongrass is used to inhibit or kill pathogenic bacteria because it contains essential oils that function as an antifungal and antibacterial against several pathogenic bacteria such as Staphylococcus aureus and Escherichia coli. The laboratory experiment method tested the antibacterial activity of endophytic fungi isolates obtained from lemongrass (Cymbopogon citratus) against Staphylococcus aureus and Escherichia coli using hole / well method. From the results of the study, four endophytic fungi were isolated from the roots and leaves of lemongrass (Cymbopogon citratus). Antibacterial results showed that endophytic fungi extract isolated from lemongrass plants was more effective in inhibiting Staphylococcus aureus compared to Escherichia coli bacteria. In Staphylococcus aureus bacteria the average inhibitory value is 5-9 mm while in Escherichia coli bacteria the average inhibitory value is only 3 mm. Endophytic fungi from lemongrass roots have a better antibacterial effect compared to endophytic fungi from lemongrass leaves. Conclusion, endophytic fungi isolated from the roots and leaves of lemongrass (Cymbopogon citratus) have an antibacterial effect on the growth of S. aureus bacteria and are not effective against E. coli bacteria. This endophytic fungus isolate is more active against Gram positive (+) bacteria and less active against Gram negative (-) bacteria. Keywords: Lemongrass plants, Endophytic Fungi, Antibacterial Activity, Staphylococcus aureus,  Escherichia coli. ABSTRAK Jamur endofit ialah jamur yang hidup di dalam jaringan tumbuhan dan tidak membahayakan tumbuhan tersebut. Jamur endofit dapat menghasilkan senyawa yang berpotensi sebagai antibakteri. Penelitian ini bertujuan untuk menguji efek antibakteri jamur endofit yang diisolasi dari akar,batang dan daun tumbuhan sereh (Cymbopogon citratus)  terhadap bakteri Staphylococcus aureus dan Escherichia coli. Sereh digunakan untuk menghambat atau membunuh bakteri patogen karena mengandung minyak atsiri yang berfungsi sebagai antijamur dan antibakteri terhadap beberapa bakteri patogen seperti Staphylococcus aureus dan  Escherichia coli.  Metode penelitian secara eksperimen laboratorium menguji aktivitas antibakteri dari isolat jamur endofit  yang diperoleh dari tumbuhan sereh (Cymbopogon citratus) pada bakteri Staphylococcus Aureus dan Escherichia Coli menggunakan metode lubang/sumuran. Dari hasil penelitan diperoleh empat jenis jamur endofit yang diisolasi dari akar dan daun  tumbuhan sereh (Cymbopogon citratus).  Hasil penelitian antibakteri menunjukkan bahwa ekstrak jamur endofit yang diisolasi dari tumbuhan sereh lebih efektif menghambat  bakteri Staphylococcus aureus dibandingkan dengan bakteri Escherichia coli. Pada bakteri  Staphylococcus aureus nilai rata-rata daya hambat yaitu 5-9 mm sedangkan pada bakteri Escherichia coli nilai rata-rata daya hambat yaitu hanya 3 mm. Jamur endofit dari akar sereh memiliki efek antibakteri yang lebih baik dibandingkan dengan jamur endofit dari daun sereh. Kesimpulan, Jamur endofit yang diisolasi dari akar  dan daun sereh (Cymbopogon citratus) memiliki efek antibakteri terhadap pertumbuhan bakteri S. aureus dan tidak efektiv terhadap bakteri E. coli. Isolat jamur endofit ini lebih aktif pada bakteri Gram positif (+) dan kurang  aktif pada bakteri negatif (-). Kata Kunci : Tumbuhan Sereh, Jamur Endofit, Aktivitas Antibakteri, Staphylococcus aureus, Escherichia coli

scholarly journals Detection of Escherichia Coli Bacteria in Water Using Deep Learning

2020 ◽  
Vol 14 (3) ◽  
pp. 273-280
Author(s):  
Hüseyin Yanik ◽  
Ahmet Hilmi Kaloğlu ◽  
Evren Değirmenci
Keyword(s):  
Escherichia Coli ◽  
Deep Learning ◽  
Pathogenic Bacteria ◽  
Color Change ◽  
Agar Medium ◽  
Detection Scheme ◽  
E Coli ◽  
Naked Eye ◽  
Metabolic Activities ◽  
Escherichia Coli Bacteria

Considering its importance for vital activities, water and particularly drinking water should be clean and should not contain disease-causing bacteria. One of the pathogenic bacteria found in water is the bacterium Escherichia coli (E. coli). In the commonly used method for the detection of E. coli bacteria, the bacteria samples distilled from the water sample are seeded in endo agar medium and the change in the color of the medium as a result of the metabolic activities of the bacteria is examined with the naked eye. This color change can be seen with the human eye in approximately 22 ± 2 hours. In this study, a new bacteria detection scheme is proposed – using deep learning to detect E. coli bacteria both in shorter time and in practical way. The proposed technique is tested with experimentally collected data. Results show that the detection of bacteria can be done automatically within 6-10 hours with the proposed method.

scholarly journals Vital Staining of Bacteria by Sunset Yellow Pigment

2017 ◽  
Vol 66 (1) ◽  
pp. 113-117 ◽  
Author(s):  
Peng Gao ◽  
Chengming Sun ◽  
Yuxia Li ◽  
Xiaohua Zou ◽  
Xun Wu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacillus Subtilis ◽  
Pathogenic Bacteria ◽  
Shigella Flexneri ◽  
Vital Staining ◽  
Yellow Pigment ◽  
Sunset Yellow ◽  
E Coli ◽  
Escherichia Coli Bacteria

In this study, we describe a method for discriminating pathogenic bacteria with a dye. First, we determined that among several colours tested, the sunset yellow pigment easily coloured Escherichia coli bacteria yellow. Next, we demonstrated that E. coli O157:H7, Shigella flexneri O301, Staphylococcus aureus and Bacillus subtilis could all be well marked by sunset yellow pigment. Finally, we performed bacterial viability assays and found there was no effect on bacterial growth when in co-culture with sunset yellow. Our results suggest that sunset yellow is suitable pigment to dye microorganisms.

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 Molecular characterization and antimicrobial resistance of potentially human‐pathogenic Escherichia coli strains isolated from riding horses

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Pouya Reshadi ◽  
Fatemeh Heydari ◽  
Reza Ghanbarpour ◽  
Mahboube Bagheri ◽  
Maziar Jajarmi ◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Health Concern ◽  
Zoonotic Potential ◽  
Drug Resistant ◽  
Public Health Concern ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Amoxicillin Clavulanic Acid

Abstract Background Transmission of antimicrobial resistant and virulent Escherichia coli (E. coli) from animal to human has been considered as a public health concern. This study aimed to determine the phylogenetic background and prevalence of diarrheagenic E. coli and antimicrobial resistance in healthy riding-horses in Iran. In this research, the genes related to six main pathotypes of E. coli were screened. Also, genotypic and phenotypic antimicrobial resistance against commonly used antibiotics were studied, then phylo-grouping was performed on all the isolates. Results Out of 65 analyzed isolates, 29.23 % (n = 19) were determined as STEC and 6.15 % (n = 4) as potential EPEC. The most prevalent antimicrobial resistance phenotypes were against amoxicillin/clavulanic acid (46.2 %) and ceftriaxone (38.5 %). blaTEM was the most detected resistance gene (98.4 %) among the isolates and 26.15 % of the E. coli isolates were determined as multi-drug resistant (MDR). Three phylo-types including B1 (76.92 %), A (13.85 %) and D (3.08 %) were detected among the isolates. Conclusions Due to the close interaction of horses and humans, these findings would place emphasis on the pathogenic and zoonotic potential of the equine strains and may help to design antimicrobial resistance stewardship programs to control the dissemination of virulent and multi-drug resistant E. coli strains in the community.

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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