A new multiplex PCR for differential identification ofShigella flexneriandShigella sonneiand detection ofShigellavirulence determinants

2009 ◽  
Vol 138 (4) ◽  
pp. 525-533 ◽  
Author(s):  
M. J. FARFÁN ◽  
T. A. GARAY ◽  
C. A. PRADO ◽  
I. FILLIOL ◽  
M. T. ULLOA ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Pathogenicity Island ◽  
Virulence Determinants ◽  
Specific Primers ◽  
Geographic Locations ◽  
Enterotoxin Genes ◽  
Differential Identification

SUMMARYMost of the multiplex PCR (mPCR) used to identifyShigellado not discriminate betweenShigellaspecies or serotypes. We designed a mPCR to differentiate betweenS. flexneriandS. sonneistrains based on the detection of markers associated with theshepathogenicity island described inShigella. In addition, specific primers were included to detect theShigellavirulence determinants ShET-1 and ShET-2 enterotoxin genes. The analysis of 304Shigellastrains from Chile and 79Shigellastrains from other geographic locations indicated that the mPCR described here detected allShigellaspecies and specifically differentiatedS. flexneriandS. sonnei. The technique was sensitive, reproducible, specific and simple to perform, providing a new tool with the potential to be employed for epidemiological and diagnostic purposes.

scholarly journals Development of a Single-Reaction Multiplex PCR Toxin Typing Assay for Staphylococcus aureusStrains

2000 ◽  
Vol 66 (4) ◽  
pp. 1347-1353 ◽  
Author(s):  
Naresh K. Sharma ◽  
Catherine E. D. Rees ◽  
Christine E. R. Dodd
Keyword(s):  
Multiplex Pcr ◽  
Toxin Gene ◽  
Gene Products ◽  
Pcr Assay ◽  
Specific Primers ◽  
Purification Method ◽  
Multiplex Pcr Assay ◽  
Enterotoxin Genes ◽  
Immunological Tests ◽  
Single Reaction

ABSTRACT We describe here the development of a single-reaction multiplex PCR assay for the enterotoxin genes from Staphylococcus aureusthat utilizes a universal toxin gene primer in combination with toxin-specific primers to amplify characteristic toxin gene products. In combination with a new DNA purification method, the assay can detect enterotoxin genes A to E from a pure culture within 3 to 4 h. The test was used to characterize a diverse set of environmental S. aureus isolates, and a 99% correlation with toxin typing using standard immunological tests was found. The design of the assay allows it to be extended to include both newly characterized and as-yet-unknown toxin genes.

scholarly journals Multiplex PCR Method for Detection of Three Aeromonas Enterotoxin Genes

2009 ◽  
Vol 76 (2) ◽  
pp. 425-433 ◽  
Author(s):  
Cesar I. Bin Kingombe ◽  
Jean-Yves D'Aoust ◽  
Geert Huys ◽  
Lisa Hofmann ◽  
Mary Rao ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Hypothetical Protein ◽  
Aeromonas Salmonicida ◽  
Specific Primers ◽  
Heat Stable ◽  
Food Borne ◽  
Enterotoxin Genes ◽  
Pcr Method ◽  
Reference Strains

ABSTRACT A novel multiplex PCR method using three sets of specific primers was developed for the detection of the cytotoxic (act), heat-labile (alt), and heat-stable (ast) enterotoxin genes in Aeromonas spp. This assay was used to characterize 35 reference strains as well as 537 food-borne isolates. A total of seven gene pattern combinations were encountered, including act, alt, act/alt, act/alt/ast, act/alt/148-bp amplicon, alt/ast, and alt/148-bp amplicon. The alt gene was detected with 34 reference strains (97%) and occurred singly in 14% of these strains. The frequency of occurrence of the act/alt, act/alt/ast, and alt/ast gene patterns in reference strains was 14 (40%), 2 (6%), and 2 (6%), respectively. An unpredicted amplicon was detected in 11 reference strains (31%). Characterization of this amplicon showed that its size was 148 bp, as generated by the AHLF and AHLR primers, and that it uniquely aligned with the Aeromonas salmonicida A449 genome sequence (GenBank accession number CP000644). This amplicon was named Aeromonas salmonicida subsp. salmonicida hypothetical protein amplicon (AssHPA). In the 537 food-borne isolates, the act and alt genes were most dominant and were detected in 349 (65%) and 452 (84%) isolates, respectively, either alone or in combinations. The act and alt genes occurred singly in 30 (6%) and 128 (24%) of these strains, respectively. The act/alt gene pattern occurred in 315 isolates (59%), whereas the ast gene was always linked to strains exhibiting the act/alt/ast and alt/ast gene combinations in 4 (0.7%) and 5 (0.9%) isolates, respectively. The uniplex amplification of three enterotoxin genes separately confirms the specificity of the unique selected primers. This multiplex PCR is rapid and simple and can detect the presence of three Aeromonas enterotoxin genes in a single assay.

Multiplex PCR Detection of Enterotoxin Genes in Aeromonas spp. from Suspect Food Samples in Northern Taiwan

2008 ◽  
Vol 71 (10) ◽  
pp. 2094-2099 ◽  
Author(s):  
YU-CHANG CHANG ◽  
JAN-YI WANG ◽  
AMMAIYAPPAN SELVAM ◽  
SHU-CHEN KAO ◽  
SHANG-SHYNG YANG ◽  
...  
Keyword(s):  
Multiplex Pcr ◽  
Diarrheal Disease ◽  
Simultaneous Detection ◽  
Food Poisoning ◽  
Food Samples ◽  
Pcr Assay ◽  
Multiplex Pcr Assay ◽  
Enterotoxin Genes ◽  
Causative Agents ◽  
Northern Taiwan

Aeromonads possess an array of virulence factors and are causative agents of a number of human infections. Among them, genes of one cytotoxic (Act) and two cytotonic (Alt, Ast) enterotoxins are implicated in a human diarrheal disease. A rapid, specific, simultaneous detection of these enterotoxin genes in suspected food poisoning samples is not yet reported. Hence, a multiplex PCR assay was designed to amplify the cytotoxic (act), heat-labile cytotonic (alt), and heat-stable cytotonic (ast) enterotoxin genes of aeromonads. The PCR assay was tested with 133 Aeromonas spp. isolated from suspect food poisoning samples and retail samples of poultry and fish from wet markets in and around Taipei, Northern Taiwan. The Aeromonas spp. isolates were divided into six genotypes based on absence or presence of one or more enterotoxin genes. Of these 133 isolates, Aeromonas caviae (52.5%) and Aeromonas hydrophila (43.4%) were the most frequently isolated species from food poisoning samples and retail samples, respectively. Among the species, A. hydrophila had a significantly higher proportion for harboring three enterotoxin genes than had the others, whereas Aeromonas encheleia, considered a nonpathogen, was found harboring three enterotoxin genes. The multiplex PCR assays are rapid and specific, and provide a useful tool for the detection and genotyping of enterotoxin genes of aeromonads.

scholarly journals Multiplex PCR with 16S rRNA Gene-Targeted Primers of Bifidobacterium spp. To Identify Sources of Fecal Pollution

2004 ◽  
Vol 70 (5) ◽  
pp. 3171-3175 ◽  
Author(s):  
X. Bonjoch ◽  
E. Ballesté ◽  
A. R. Blanch
Keyword(s):  
16S Rrna ◽  
Multiplex Pcr ◽  
Fecal Pollution ◽  
Sensitivity Threshold ◽  
Rrna Gene ◽  
Specific Primers ◽  
Animal Wastewater ◽  
Wastewater Samples ◽  
Species Specific ◽  
Different Origins

ABSTRACT Bifidobacteria are one of the most common bacterial types found in the intestines of humans and other animals and may be used as indicators of human fecal pollution. The presence of nine human-related Bifidobacterium species was analyzed in human and animal wastewater samples of different origins by using species-specific primers based on 16S rRNA sequences. Only B. adolescentis and B. dentium were found exclusively in human sewage. A multiplex PCR approach with strain-specific primers was developed. The method showed a sensitivity threshold of 10 cells/ml. This new molecular method could provide useful information for the characterization of fecal pollution sources.

scholarly journals The organization of Helicobacter pylori cag-pathogenicity island (cagPAI) genes in multiracial population with histopathological changes of gastric mucosa

2019 ◽  
Author(s):  
Alfizah Hanafiah ◽  
Shaza Azlin Razak ◽  
Hui-min Neoh ◽  
Noraziah Mohamad Zin ◽  
Bruno S. Lopes
Keyword(s):  
Helicobacter Pylori ◽  
Gastric Mucosa ◽  
Pathogenicity Island ◽  
Type Iv Secretion ◽  
Virulence Determinants ◽  
Gastric Diseases ◽  
Cag Pathogenicity Island ◽  
Type Iv ◽  
Inflammatory Score ◽  
H Pylori

Abstract Background: Helicobacter pylori is a Gram-negative bacillus that colonises only the mucus layer of the human stomach and is implicated in gastric diseases. Virulent H. pylori harbouring cag-pathogenicity island (cagPAI) which encodes genes for type IV secretion system (T4SS) and CagA protein is one of the major virulence determinants involved in disease development. We examined the entire cagPAI genes in 95 H. pylori isolates from a multiracial population and examined the intactness of cagPAI region with histopathological scores of the gastric mucosa. Results: 95.8% of H. pylori isolates were cagPAI-positive with 23.2% having an intact cagPAI, whereas 72.6% had a partial/rearranged cagPAI. In our study, cag2 and cag4 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominant in Chinese isolates. We also detected cag24 in significantly high proportion in isolates from the Malays and the Indians compared to the Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI and higher density of H. pylori and neutrophil activity, whereas strains which lacked cagPAI was associated with higher inflammatory score. Conclusions: The screening of the entire cagPAI genes provides an accurate overview of the cagPAI organisation in H. pylori isolates in a multiracial population. The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients’ ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

scholarly journals Ocurrence of Staphylococcus aureus and multiplex pcr detection of classic enterotoxin genes in cheese and meat products

2009 ◽  
Vol 40 (1) ◽  
pp. 145-148 ◽  
Author(s):  
Marcia Regina Pelisser ◽  
Cátia Silene Klein ◽  
Kelen Regina Ascoli ◽  
Thaís Regina Zotti ◽  
Ana Carolina Maisonnave Arisi
Keyword(s):  
Staphylococcus Aureus ◽  
Multiplex Pcr ◽  
Meat Products ◽  
Pcr Detection ◽  
Enterotoxin Genes

a Novel Method for the Detection of Minimal Residual Disease in B-Cell Malignancies: Ion Semiconductor Sequencing for the Evaluation of Igh Gene Rearrangements

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2983-2983
Author(s):  
Silvia Gimondi ◽  
Alessandra Cavanè ◽  
Antonio Vendramin ◽  
Giulia Biancon ◽  
Paolo Corradini ◽  
...  
Keyword(s):  
B Cell ◽  
Multiplex Pcr ◽  
Residual Disease ◽  
Chain Reaction ◽  
B Cell Malignancies ◽  
Specific Primers ◽  
Namalwa Cell ◽  
Polymerase Chain ◽  
Minimal Residual

Abstract Background: Minimal residual disease (MRD) detection is of high clinical relevance in patients with B-cell malignancies and is generally a surrogate parameter to evaluate treatment response and long-term prognosis. IgH gene rearrangements can be used as molecular marker in approximately 80% of lymphoma and myeloma patients since they represent lineage-specific markers and the complementarity determining region 3 (CDR3) is unique to each clone. To date, allele specific oligonucleotide polymerase chain reaction (ASO-PCR) and real-time quantitative polymerase chain reaction (RQ-PCR) are considered the most sensitive and widely applicable methods for MRD detection. A major disadvantage of ASO-PCR and RQ-PCR assays, is the use of specific primers and probes for every individual patient. Clone-specific primers and probes are not only expensive but also time-consuming to design and to test, which limits their wide applicability in the clinical setting. The recent major improvements in next generation sequencing (NGS) technologies, provide the opportunity to identify and quantify clonotypes with consensus primers combining the benefits of high sensitivity and universal applicability. The present work was designed to overcome ASO-PCR and RQ-PCR limitations by developing a feasible method for rearranged IgH genes amplification, NGS and analysis using Ion Torrent Personal Genome Machine (IT-PGM). Methods: To define a multiplex PCR protocol, DNA from 7 CLL patients, previously shown to bare a family specific clonal VDJ rearrangement, was amplified with a pool of the seven different family-specific IgH-V primers, and a consensus JH primer (Voena et al., Leukemia 1997). After Sanger sequencing, results were compared to the ones obtained with singleplex PCR protocol. Once validated, the multiplex PCR protocol was used to amplify DNA from patients and serially diluted (up to 10-8 ) DNA from Namalwa cell line (bearing a known IgH rearrangement) and subsequently sequenced on the IT-PGM using the 316 Ion-chip. NGS data were analyzed by using the IMGT-High V-Quest web server tool and the statistical software R. RQ-PCR was used to quantify the specific VDJ rearrangement in the serially diluted Namalwa DNA solutions and in DNA from patients as previously described (Farina et al, Haematologica 2009). RQ-PCR data were analyzed through a relative quantification procedure. Results: The multiplex PCR reactions we have tested, demonstrated the same specificity as the standard singleplex PCR protocol and therefore was used to construct the DNA library required for IT-PGM-based sequencing. The IT-PGM sequencing output is represented by at least 400000 reads per sample with a minimum average coverage of the VDJ repertoire of 500x. The IMGT-High V-quest tool allows a user-friendly web based analysis and a deep molecular characterization of the IgH recombinatorial repertoire. Namalwa clonal CRD3 sequences were detected up to a dilution of 10-5 without the need for specific CDR3 primers. Comparability of NGS and ASO RQ-PCR results was assessed. The use of CDR3 specific primers, along with the specific IgH-V family fluorescent probe, enabled the identification of clonal VDJ rearrangements with a sensitivity up to 10-5 (2/3 replicates) and 10-6 (just 1/3 replicates) in Namalwa Cell Line. Similar results were obtained when we characterized the IgH recombination repertoire of two CLL patients over time. Conclusions: IgH sequencing with the IT-PGM platform showed at least the same level of sensitivity as ASO RQ-PCR, without the need for patient-specific reagents. It also allows specific and detailed molecular characterization of the clonal rearrangements and could be easily incorporated into clinical laboratories for routine testing of MRD in B-cell malignancies. Disclosures No relevant conflicts of interest to declare.

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