scholarly journals Trapping and breaking of in vivo nicked DNA during pulsed field gel electrophoresis

2013 ◽  
Vol 443 (2) ◽  
pp. 269-281 ◽  
Author(s):  
Sharik R. Khan ◽  
Andrei Kuzminov
Keyword(s):  
Gel Electrophoresis ◽  
Pulsed Field Gel Electrophoresis ◽  
Pulsed Field

scholarly journals Application of Pulsed-Field Gel Electrophoresis and Binary Typing as Tools in Veterinary Clinical Microbiology and Molecular Epidemiologic Analysis of Bovine and HumanStaphylococcus aureus Isolates

2000 ◽  
Vol 38 (5) ◽  
pp. 1931-1939 ◽  
Author(s):  
Ruth Zadoks ◽  
Willem van Leeuwen ◽  
Herman Barkema ◽  
Otlis Sampimon ◽  
Henri Verbrugh ◽  
...  
Keyword(s):  
Host Species ◽  
Gel Electrophoresis ◽  
Genetic Relatedness ◽  
Pulsed Field Gel Electrophoresis ◽  
Simple Method ◽  
Pulsed Field ◽  
Strain Characterization ◽  
Single Host

Thirty-eight bovine mammary Staphylococcus aureusisolates from diverse clinical, temporal, and geographical origins were genotyped by pulsed-field gel electrophoresis (PFGE) afterSmaI digestion of prokaryotic DNA and by means of binary typing using 15 strain-specific DNA probes. Seven pulsed-field types and four subtypes were identified, as were 16 binary types. Concordant delineation of genetic relatedness was documented by both techniques, yet based on practical and epidemiological considerations, binary typing was the preferable method. Genotypes of bovine isolates were compared to 55 previously characterized human S. aureusisolates through cluster analysis of binary types. Genetic clusters containing strains of both human and bovine origin were found, but bacterial genotypes were predominantly associated with a single host species. Binary typing proved an excellent tool for comparison ofS. aureus strains, including methicillin-resistant S. aureus, derived from different host species and from different databases. For 28 bovine S. aureus isolates, detailed clinical observations in vivo were compared to strain typing results in vitro. Associations were found between distinct genotypes and severity of disease, suggesting strain-specific bacterial virulence. Circumstantial evidence furthermore supports strain-specific routes of bacterial dissemination. We conclude that PFGE and binary typing can be successfully applied for genetic analysis of S. aureusisolates from bovine mammary secretions. Binary typing in particular is a robust and simple method and promises to become a powerful tool for strain characterization, for resolution of clonal relationships of bacteria within and between host species, and for identification of sources and transmission routes of bovine S. aureus.

The Predominance of Strain Replacement Among Enterobacteriaceae Pairs With Emerging Carbapenem Resistance During Hospitalization

2020 ◽  
Vol 221 (Supplement_2) ◽  
pp. S215-S219
Author(s):  
Baixing Ding ◽  
Zhen Shen ◽  
Xiaohua Qin ◽  
Yang Yang ◽  
Xiaogang Xu ◽  
...  
Keyword(s):  
Antimicrobial Therapy ◽  
Gel Electrophoresis ◽  
Carbapenem Resistance ◽  
Tertiary Hospital ◽  
Pulsed Field Gel Electrophoresis ◽  
Pulsed Field ◽  
Carbapenem Resistant ◽  
Sequence Types ◽  
Carbapenem Resistant Enterobacteriaceae

Abstract Isolates of Enterobacteriaceae collected from the same patient can lose carbapenem susceptibility during antimicrobial therapy, but little attention has been given to how this conversion takes place. In the current study, we retrospectively analyzed microbiological and clinical data from patients with enterobacterial infections at a tertiary hospital in Shanghai, China. After screening 4795 patients and 7120 Enterobacteriaceae isolates over the 3-year study period, we found the change from carbapenem susceptible to carbapenem resistant in 41 pairs of isolates, of which 35 pairs (85.4%) were K. pneumoniae and 25 (61.0%) were from the same anatomic sites. Thirty-six isolate pairs showed different pulsed-field gel electrophoresis patterns between the carbapenem-susceptible and the corresponding resistant strain, and 5 pairs displayed identical pulsed-field gel electrophoresis patterns. Thirty-three (91.7%) of the 36 pairs of Enterobacteriaceae isolates were carbapenem-resistant K. pneumoniae with blaKPC-2, and 28 pairs (90.3%) of K. pneumoniae isolates had different sequence types (STs), with ST11 the most common ST found in carbapenem-resistant K. pneumoniae isolates. Forty of the 41 patients had received antimicrobial therapy such as carbapenems, cephalosporins, and fluoroquinolones, before the isolation of carbapenem-resistant Enterobacteriaceae. These results demonstrated that strain replacement is the main cause of emerging carbapenem resistance in Enterobacteriaceae during hospitalization. The loss of carbapenem susceptibility was not mainly due to in vivo development of carbapenem resistance.

scholarly journals In Vitro and In Vivo Invasiveness of Different Pulsed-Field Gel Electrophoresis Types of Listeria monocytogenes

2002 ◽  
Vol 68 (11) ◽  
pp. 5698-5703 ◽  
Author(s):  
Charlotte Nexmann Larsen ◽  
Birgit Nørrung ◽  
Helle Mølgaard Sommer ◽  
Mogens Jakobsen
Keyword(s):  
Listeria Monocytogenes ◽  
Gel Electrophoresis ◽  
Pulsed Field Gel Electrophoresis ◽  
In Vivo Studies ◽  
Pfge Type ◽  
Pulsed Field ◽  
Lower Ability ◽  
Low Prevalence

ABSTRACT The virulence of different pulsed-field gel electrophoresis (PFGE) types of Listeria monocytogenes was examined by monitoring their ability to invade Caco-2 cells. Strains belonging to seven different PFGE types originating from both foods and humans were included. No significant differences in invasiveness were detected between strains isolated from humans and those isolated from food. Strains belonging to PFGE type 1 expressed a significantly lower ability to invade cells compared to strains belonging to other PFGE types. Although strains of PFGE type 2 also seemed to invade at a low level, this was not significant in the present study. PFGE types 1 and 2 as well as type 14 are more frequently found in food than the four other PFGE types examined and moreover have a relatively low prevalence in humans compared to their prevalence in food. Thus, the hypothesis that some PFGE types are less virulent than others is supported by this study showing that certain PFGE types of L. monocytogenes commonly found in food are less invasive than others to Caco-2 cells. In contrast to the differences in invasion, identical intracellular growth rates between the different PFGE types were observed. In vivo studies of the actual ability of the strains to invade the liver and spleen of cimetidine-treated rats following an oral dose of 109 L. monocytogenes cells were performed for isolates of PFGE types 1, 2, 5, and 15. After 2 days, equal amounts of bacteria were observed in the liver and spleen of the rats for any of the PFGE types tested.

scholarly journals Use of Pulsed-Field Gel Electrophoresis to Determine the Source of Methicillin-Resistant Staphylococcus aureus Bacteremia

2021 ◽  
Vol 13 (3) ◽  
pp. 602-610
Author(s):  
Eugene Y. H. Yeung ◽  
Ivan Gorn
Keyword(s):  
Staphylococcus Aureus ◽  
Gel Electrophoresis ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Epidemiological Studies ◽  
Pelvic Trauma ◽  
Pulsed Field Gel Electrophoresis ◽  
Bacterial Strains ◽  
Methicillin Resistant ◽  
Pulsed Field ◽  
Clinical Cases

Pulsed-field gel electrophoresis (PFGE) has historically been considered the gold standard in fingerprinting bacterial strains in epidemiological studies and outbreak investigations; little is known regarding its use in individual clinical cases. The current study detailed two clinical cases in which PFGE helped to determine the source of their methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Patient A was found to have MRSA bacteremia after trauma in her pelvic area. MRSA was also found in her groin but not in her nostril and rectum. PFGE was performed that showed variable bands of her MRSA isolates from blood and groin, suggestive of different strains of MRSA. Her MRSA bacteremia was determined to be unrelated to her pelvic trauma. Patient B was found to have MRSA bacteremia after colonoscopy. MRSA was also found in his nostril and rectum. PFGE was performed that showed variable bands of his MRSA isolates from blood and rectum but identical bands of MRSA isolates from his blood and nostril. His MRSA bacteremia was determined to be unrelated to his colonoscopy procedure. The current study demonstrates the use of PFGE to rule out the source of bacteremia in individual clinical cases.

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