A molecular beacon DNA microarray system for rapid detection of E. coli O157:H7 that eliminates the risk of a false negative signal

2007 ◽  
Vol 22 (6) ◽  
pp. 1041-1047 ◽  
Author(s):  
Hanyoup Kim ◽  
Michael D. Kane ◽  
Sol Kim ◽  
Wilfredo Dominguez ◽  
Bruce M. Applegate ◽  
...  
2020 ◽  
Author(s):  
Diana Elizabeth Waturangi ◽  
JASON PETRUS ◽  
RICO KOSASIH ◽  
GLORIA RAISSA

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.


2021 ◽  
pp. e299
Author(s):  
Diana Elizabeth Waturangi ◽  
Jason Petrus ◽  
Rico Kosasih ◽  
Felicia Roseline

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.


1997 ◽  
Vol 60 (3) ◽  
pp. 219-225 ◽  
Author(s):  
RUTH FIRSTENBERG-EDEN ◽  
NADINE M. SULLIVAN

The EZ Coli™ Rapid Detection System consists of a selective enrichment medium and a rapid immunological detection kit. After being incubated for 15 to 24 h at 40 to 42°C, an Escherichia coli O157 culture was at a sufficient cell concentration (> 106 CFU/ml) to be tested with the EZ Coli Detection Kit. In studies of foods seeded with E. coli O157, all 42 strains of E. coli O157 tested positive with the detection kit. None of the 29 strains of E. coli non-O157 tested positive with the kit. Species of Citrobacter, Hafnia, and Klebsiella grew in the medium but tested negative. Of the 47 strains of non-E. coli O157 tested, only two strains of Salmonella 0 Group N grew and tested positive with the kit. Several laboratories evaluated the EZ Coli System with 378 clean and naturally contaminated food samples (mainly raw beef), and 337 different food samples, including raw meats (beef, pork, turkey, and chicken), dairy products, spices, vegetables, and apple cider, spiked with 50 different strains of E. coli O157 (1 to 100 CFU/25 g). Of these samples, 44.6% were positive and 52.2% were negative. The false-positive rate was 1.7% and the false-negative rate was 1.5%. The data show that high levels of coliforms (> 106 CFU/g) in food samples may impede the detection of low levels (1 to 10 CFU/25 g) of E. coli O157 organisms in broth, thereby causing false-negative reactions with most detection systems. The EZ Coli Rapid Detection System provides a rapid and specific means of detecting E. coli O157 in raw and processed foods.


Author(s):  
Cheng Liu ◽  
Shuiqin Fang ◽  
Yachen Tian ◽  
Youxue Wu ◽  
Meijiao Wu ◽  
...  

Escherichia coli O157:H7 ( E. coli O157:H7) is a dangerous foodborne pathogen, mainly found in beef, milk, fruits, and their products, causing harm to human health or even death. Therefore, the detection of E. coli O157:H7 in food is particularly important. In this paper, we report a lateral flow immunoassay strip (LFIS) based on aggregation-induced emission (AIE) material labeling antigen as a fluorescent probe for the rapid detection of E. coli O157:H7. The detection sensitivity of the strip is 105 CFU/mL, which is 10 times higher than that of the colloidal gold test strip. This method has good specificity and stability and can be used to detect about 250 CFU of E. coli O157:H7 successfully in 25 g or 25 mL of beef, jelly, and milk. AIE-LFIS might be valuable in monitoring food pathogens for rapid detection.


2013 ◽  
Vol 57 (9) ◽  
pp. 4578-4580 ◽  
Author(s):  
Nathalie Tijet ◽  
David Boyd ◽  
Samir N. Patel ◽  
Michael R. Mulvey ◽  
Roberto G. Melano

ABSTRACTThe Carba NP test was evaluated against a panel of 244 carbapenemase- and non-carbapenemase-producingEnterobacteriaceaeandPseudomonas aeruginosaisolates. We confirmed the 100% specificity and positive predictive value of the test, but the sensitivity and negative predictive value were 72.5% and 69.2%, respectively, and increased to 80% and 77.3%, respectively, using a more concentrated bacterial extract. False-negative results were associated with mucoid strains or linked to enzymes with low carbapenemase activity, particularly OXA-48-like, which has emerged globally in enterobacteria.


1999 ◽  
Vol 14 (3) ◽  
pp. 309-316 ◽  
Author(s):  
Ihab Abdel-Hamid ◽  
Dmitri Ivnitski ◽  
Plamen Atanasov ◽  
Ebtisam Wilkins

The Analyst ◽  
2016 ◽  
Vol 141 (18) ◽  
pp. 5441-5449 ◽  
Author(s):  
Meng Xu ◽  
Ronghui Wang ◽  
Yanbin Li

An electrochemical biosensor was developed based on the bifunctional ABs/GOxext/AuNPs/MBs-GOx@PDA magnetic PMNCs that can rapidly and sensitively detect E. coli O157:H7.


2003 ◽  
Vol 69 (6) ◽  
pp. 3492-3499 ◽  
Author(s):  
Yang Hong ◽  
Mark E. Berrang ◽  
Tongrui Liu ◽  
Charles L. Hofacre ◽  
Susan Sanchez ◽  
...  

ABSTRACT Contamination of retail poultry by Campylobacter spp. and Salmonella enterica is a significant source of human diarrheal disease. Isolation and identification of these microorganisms require a series of biochemical and serological tests. In this study, Campylobacter ceuE and Salmonella invA genes were used to design probes in PCR-enzyme-linked immunosorbent assay (ELISA), as an alternative to conventional bacteriological methodology, for the rapid detection of Campylobacter jejuni, Campylobacter coli, and S. enterica from poultry samples. With PCR-ELISA (40 cycles), the detection limits for Salmonella and Campylobacter were 2 � 102 and 4 � 101 CFU/ml, respectively. ELISA increased the sensitivity of the conventional PCR method by 100- to 1,000-fold. DNA was extracted from carcass rinses and tetrathionate enrichments and used in PCR-ELISA for the detection of Campylobacter and S. enterica, respectively. With PCR-ELISA, Salmonella was detected in 20 of 120 (17%) chicken carcass rinses examined, without the inclusion of an enrichment step. Significant correlation was observed between PCR-ELISA and cultural methods (kappa = 0.83; chi-square test, P < 0.001) with only one false negative (1.67%) and four false positives (6.67%) when PCR-ELISA was used to screen 60 tetrathionate enrichment cultures for Salmonella. With PCR-ELISA, we observed a positive correlation between the ELISA absorbance (optical density at 405 nm) and the campylobacter cell number in carcass rinse, as determined by standard culture methods. Overall, PCR-ELISA is a rapid and cost-effective approach for the detection and enumeration of Salmonella and Campylobacter bacteria on poultry.


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