Establishment and Application of a Dual TaqMan Real-Time PCR Methodfor Proteus mirabilis and Proteus vulgaris

Proteus species are common opportunistic bacteria and foodborne pathogens. The proper detection of Proteus can effectively reduce the occurrence of food-borne public health events. Proteus mirabilis and Proteus vulgaris are the two most important pathogens in the Proteus genus. In this study, a dual TaqMan Real-Time PCR method was established to simultaneously detect and distinguish P. mirabilis and P. vulgaris in samples. The method exhibited good specificity, stability, and sensitivity. Specifically, the minimum detection concentrations of P. mirabilis and P. vulgaris in pure bacterial cultures were 6.08 × 102 colony forming units (CFU)/ml and 4.46 × 102 CFU/ml, respectively. Additionally, the minimum detectable number of P. mirabilis and P. vulgaris in meat and milk was 103 CFU/g. In addition, the method can be used to distinguish between strains of P. mirabilis and P. vulgaris within two hours. Overall, it is a sensitive, easy-to-use, and practical test for the identification and classification of Proteus in food.

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Use of Ethidium Monoazide and PCR in Combination for Quantification of Viable and Dead Cells in Complex Samples

Applied and Environmental Microbiology ◽

10.1128/aem.71.2.1018-1024.2005 ◽

2005 ◽

Vol 71 (2) ◽

pp. 1018-1024 ◽

Cited By ~ 266

Author(s):

Knut Rudi ◽

Birgitte Moen ◽

Signe Marie Drømtorp ◽

Askild L. Holck

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Dynamic Range ◽

Covalent Binding ◽

Biological Research ◽

Complex Samples ◽

Ethidium Monoazide ◽

Food Borne ◽

Pcr Method ◽

Membrane Cell

ABSTRACT The distinction between viable and dead cells is a major issue in many aspects of biological research. The current technologies for determining viable versus dead cells cannot readily be used for quantitative differentiation of specific cells in mixed populations. This is a serious limitation. We have solved this problem by developing a new concept with the viable/dead stain ethidium monoazide (EMA) in combination with real-time PCR (EMA-PCR). A dynamic range of approximately 4 log10 was obtained for the EMA-PCR viable/dead assay. Viable/dead differentiation is obtained by covalent binding of EMA to DNA in dead cells by photoactivation. EMA penetrates only dead cells with compromised membrane/cell wall systems. DNA covalently bound to EMA cannot be PCR amplified. Thus, only DNA from viable cells can be detected. We evaluated EMA-PCR with the major food-borne bacterium Campylobacter jejuni as an example. Traditional diagnosis of this bacterium is very difficult due to its specific growth requirements and because it may enter a state where it is viable but not cultivable. The conditions analyzed included detection in mixed and natural samples, survival in food, and survival after disinfection or antibiotic treatment. We obtained reliable viable/dead quantifications for all conditions tested. Comparison with standard fluorescence-based viable/dead techniques showed that the EMA-PCR has a broader dynamic range and enables quantification in mixed and complex samples. In conclusion, EMA-PCR offers a novel real-time PCR method for quantitative distinction between viable and dead cells with potentially very wide application.

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TaqMan-Based Real-Time PCR Method for Detection of Yersinia pseudotuberculosis in Food

Applied and Environmental Microbiology ◽

10.1128/aem.01459-08 ◽

2008 ◽

Vol 74 (20) ◽

pp. 6465-6469 ◽

Cited By ~ 28

Author(s):

S. Thisted Lambertz ◽

C. Nilsson ◽

S. Hallanvuo

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Yersinia Pseudotuberculosis ◽

Internal Amplification Control ◽

Food Items ◽

Specific Assay ◽

Food Borne ◽

Pcr Method ◽

Probe Set

ABSTRACT A sensitive and specific assay for detection of food-borne pathogenic Yersinia pseudotuberculosis was developed. The primer-probe set was designed to target a 157-bp sequence of the chromosomally located gene ail. The complete method, including an internal amplification control, was evaluated for several different food items.

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Development of Simple Multiplex Real-Time PCR Assays for Foodborne Pathogens Detection and Identification On Lightcycler

Macedonian Veterinary Review ◽

10.1515/macvetrev-2017-0010 ◽

2017 ◽

Vol 40 (1) ◽

pp. 53-58 ◽

Cited By ~ 3

Author(s):

Avo Karus ◽

Fabrizio Ceciliani ◽

Armand Sanches Bonastre ◽

Virge Karus

Keyword(s):

Real Time ◽

Foodborne Pathogens ◽

Real Time Pcr ◽

Simultaneous Detection ◽

Melting Curve ◽

Food Contamination ◽

Shigella Boydii ◽

Food Borne Pathogens ◽

Detection And Identification ◽

Food Borne

Abstract Most acute intestinal diseases are caused by food-borne pathogens. A fast and simple real-time PCR-based procedure for simultaneous detection of food contamination by any of the five food-borne pathogens: Campylobacter jejuni, Mycobacterium bovis, Enterobacter sakazaki, Shigella boydii, Clostridium perfrigens using multiplex EvaGreen real-time PCR for LightCycler was developed and evaluated. Real-time qPCR showed excellent sensitivity. Tm calling and Melting Curve Genotyping (MCG) were used for analysis of PCR product melting curves. The Melting Curve Genotyping option showed good performance for discrimination of positive samples containing DNA of single pathogen or pathogen mixtures from negative samples.

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Detection of Streptococcus pneumoniae in Sputum Samples by Real- Time PCR.

Anti-Infective Agents ◽

10.2174/2211352518999200629165108 ◽

2020 ◽

Vol 18 ◽

Author(s):

Pegah Shakib ◽

Mohammad Reza Zolfaghari

Keyword(s):

Streptococcus Pneumoniae ◽

Real Time ◽

Real Time Pcr ◽

False Negative ◽

Cross Sectional Study ◽

Laboratory Culture ◽

Cross Sectional ◽

Negative Results ◽

False Negative Results ◽

Pcr Method

Background: Conventional laboratory culture-based methods for diagnosis of Streptococcus pneumoniae are time-consuming and yield false negative results. Molecular methods including real-time (RT)-PCR rapid methods and conventional PCR due to higher sensitivity and accuracy have been replaced instead traditional culture assay. The aim of the current study was to evaluate lytA gene for detection of Streptococcus pneumoniae in the cerebrospinal fluid of human patients with meningitis using real-time PCR assay. Material and Methods: In this cross-sectional study, a total of 30 clinical specimens were collected from patients in a period from September to December 2018. In order to evaluate the presence of lytA gene, conventional and real-time PCR methods were used without culture. Results: From 30 sputum samples five (16.66%) isolates were identified as S. pneumoniae by lytA PCR and sequencing. Discussion: In this research, an accurate and rapid real-time PCR method was used, which is based on lytA gene for diagnosis of bacteria so that it can be diagnosed. Based on the sequencing results, the sensitivity for detection of lytA gene was 100% (5/5).

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Real-Time PCR Assay for Detection and Enumeration of Dekkera bruxellensis in Wine

Applied and Environmental Microbiology ◽

10.1128/aem.69.12.7430-7434.2003 ◽

2003 ◽

Vol 69 (12) ◽

pp. 7430-7434 ◽

Cited By ~ 77

Author(s):

Trevor G. Phister ◽

David A. Mills

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Pcr Primers ◽

Rrna Gene ◽

Dekkera Bruxellensis ◽

Pcr Assay ◽

Specific Pcr ◽

Spoilage Yeast ◽

Pcr Method ◽

26S Rrna

ABSTRACT Traditional methods to detect the spoilage yeast Dekkera bruxellensis from wine involve lengthy enrichments. To overcome this difficulty, we developed a quantitative real-time PCR method to directly detect and enumerate D. bruxellensis in wine. Specific PCR primers to D. bruxellensis were designed to the 26S rRNA gene, and nontarget yeast and bacteria common to the winery environment were not amplified. The assay was linear over a range of cell concentrations (6 log units) and could detect as little as 1 cell per ml in wine. The addition of large amounts of nontarget yeasts did not impact the efficiency of the assay. This method will be helpful to identify possible routes of D. bruxellensis infection in winery environments. Moreover, the time involved in performing the assay (3 h) should enable winemakers to more quickly make wine processing decisions in order to reduce the threat of spoilage by D. bruxellensis.

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