scholarly journals Epidemiological Study of a Food-Borne Outbreak of EnterotoxigenicEscherichia coli O25:NM by Pulsed-Field Gel Electrophoresis and Randomly Amplified Polymorphic DNA Analysis

1998 ◽  
Vol 36 (3) ◽  
pp. 652-656 ◽  
Author(s):  
Toshihiro Mitsuda ◽  
Tetsunori Muto ◽  
Mikiko Yamada ◽  
Nobuyoshi Kobayashi ◽  
Masanori Toba ◽  
...  
Keyword(s):  
Gel Electrophoresis ◽  
Dna Analysis ◽  
Pulsed Field Gel Electrophoresis ◽  
Causal Agent ◽  
Randomly Amplified Polymorphic Dna ◽  
Pulsed Field ◽  
Food Borne ◽  
Length Polymorphisms ◽  
Genotypic Analysis ◽  
Epidemiological Characteristics

This study investigated the applicability of molecular epidemiological techniques to the identification of the causal agent of an outbreak of diarrhea caused by ingestion of food contaminated with enterotoxigenic Escherichia coli (ETEC). The outbreak occurred at four elementary schools in July 1996 and affected more than 800 people. Illness was most strongly associated with eating tuna paste (relative risk, 1.79; 95% confidence interval = 1.16 to 2.79; P = 0.0001). To evaluate the epidemiological characteristics of the pathogen, the DNAs from numerous isolated ETEC strains were subjected to randomly amplified polymorphic DNA analysis, pulsed-field gel electrophoresis of nuclease S1-treated plasmid DNA, and analysis of genomic DNA restriction fragment length polymorphisms. All ETEC isolates were of the O25:NM (nonmotile) serotype, which carries a heat-stable enterotoxin Ib gene. Genotypic analysis demonstrated that the strains isolated from the patients at all four schools were identical. The isolates of ETEC O25:NM obtained from the tuna paste that had been served for lunch at these schools were genetically indistinguishable from those isolated from the patients. Results suggest that this outbreak was food borne. The molecular biology-based epidemiological techniques used in this study were useful in characterizing the causal agent in this food-borne epidemic.

scholarly journals Comparison of Randomly Amplified Polymorphic DNA Analysis and Pulsed-Field Gel Electrophoresis for Typing of Moraxella catarrhalis Strains

1999 ◽  
Vol 37 (2) ◽  
pp. 450-452 ◽  
Author(s):  
Hoang Vu-Thien ◽  
Carole Dulot ◽  
Didier Moissenet ◽  
Brigitte Fauroux ◽  
Antoine Garbarg-Chenon
Keyword(s):  
Gel Electrophoresis ◽  
Moraxella Catarrhalis ◽  
Dna Analysis ◽  
Pulsed Field Gel Electrophoresis ◽  
Randomly Amplified Polymorphic Dna ◽  
Pulsed Field ◽  
Chronic Colonization ◽  
Different Strains

Randomly amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) for the analysis of 13 Moraxella catarrhalis isolates, 11 successive strains isolated from sputa of five children and 2 isolates obtained the same day from twins, were compared. RAPD and PFGE both yielded nine types from the 13 isolates, showing a chronic colonization with one strain in three patients and a successive colonization with different strains in two patients. The promising results obtained with RAPD should be confirmed with a larger number of strains, but RAPD seems as suitable as PFGE for the typing ofM. catarrhalis.

scholarly journals Comparison of Ribotyping, Randomly Amplified Polymorphic DNA Analysis, and Pulsed-Field Gel Electrophoresis in Typing ofLactobacillus rhamnosus and L. caseiStrains

1999 ◽  
Vol 65 (9) ◽  
pp. 3908-3914 ◽  
Author(s):  
Soile Tynkkynen ◽  
Reetta Satokari ◽  
Maria Saarela ◽  
Tiina Mattila-Sandholm ◽  
Maija Saxelin
Keyword(s):  
Gel Electrophoresis ◽  
Type Strain ◽  
Dna Analysis ◽  
Rapd Analysis ◽  
Pulsed Field Gel Electrophoresis ◽  
Strain Atcc ◽  
Randomly Amplified Polymorphic Dna ◽  
Specific Primers ◽  
Pulsed Field ◽  
Species Specific

ABSTRACT A total of 24 strains, biochemically identified as members of theLactobacillus casei group, were identified by PCR with species-specific primers. The same set of strains was typed by randomly amplified polymorphic DNA (RAPD) analysis, ribotyping, and pulsed-field gel electrophoresis (PFGE) in order to compare the discriminatory power of the methods. Species-specific primers for L. rhamnosusand L. casei identified the type strain L. rhamnosus ATCC 7469 and the neotype strain L. caseiATCC 334, respectively, but did not give any signal with the recently revived species L. zeae, which contains the type strain ATCC 15820 and the strain ATCC 393, which was previously classified asL. casei. Our results are in accordance with the suggested new classification of the L. casei group. Altogether, 21 of the 24 strains studied were identified with the species-specific primers. In strain typing, PFGE was the most discriminatory method, revealing 17 genotypes for the 24 strains studied. Ribotyping and RAPD analysis yielded 15 and 12 genotypes, respectively.

scholarly journals Identification and Characterization of Pathogenic Yersinia enterocolitica Isolates by PCR and Pulsed-Field Gel Electrophoresis

2005 ◽  
Vol 71 (7) ◽  
pp. 3674-3681 ◽  
Author(s):  
S. Thisted Lambertz ◽  
M.-L. Danielsson-Tham
Keyword(s):  
Multiplex Pcr ◽  
Yersinia Enterocolitica ◽  
Gel Electrophoresis ◽  
Pulsed Field Gel Electrophoresis ◽  
Virulence Plasmid ◽  
Pork Meat ◽  
Pulsed Field ◽  
Pork Products ◽  
Food Borne ◽  
Pork Samples

ABSTRACT Approximately 550 to 600 yersiniosis patients are reported annually in Sweden. Although pigs are thought to be the main reservoir of food-borne pathogenic Yersinia enterocolitica, the role of pork meat as a vehicle for transmission to humans is still unclear. Pork meat collected from refrigerators and local shops frequented by yersiniosis patients (n = 48) were examined for the presence of pathogenic Yersinia spp. A combined culture and PCR method was used for detection, and a multiplex PCR was developed and evaluated as a tool for efficient identification of pathogenic food and patient isolates. The results obtained with the multiplex PCR were compared to phenotypic test results and confirmed by pulsed-field gel electrophoresis (PFGE). In all, 118 pork products (91 raw and 27 ready-to-eat) were collected. Pathogenic Yersinia spp. were detected by PCR in 10% (9 of 91) of the raw pork samples (loin of pork, fillet of pork, pork chop, ham, and minced meat) but in none of the ready-to-eat products. Isolates of Y. enterocolitica bioserotype 4/O:3 were recovered from six of the PCR-positive raw pork samples; all harbored the virulence plasmid. All isolates were recovered from food collected in shops and, thus, none were from the patients' home. When subjected to PFGE, the six isolates displayed four different NotI profiles. The same four NotI profiles were also present among isolates recovered from the yersiniosis patients. The application of a multiplex PCR was shown to be an efficient tool for identification of pathogenic Y. enterocolitica isolates in naturally contaminated raw pork.

Sign in / Sign up

Export Citation Format

Share Document