• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.366-385
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• 1995

Epidemiological studies are important in both the prevention and treatment of mycobacterial infections. This study was initiated to establish the pulsed-field gel electrophoresis (PFGE) method, which are not yet extensively studied. The most apprpriate restriction endonucleases included DraI, AsnI, and XbaI. The optimal PFGE condition was different according to the enzymes used. Two stage PFGE was performed, in case of DraI first stage was performed with 10 seconds of initial pulse and 15 seconds of final pulse, while the second stage was performed with 60 seconds of initial pulse and 70 seconds of final pulse. The electrophoresis time for DraI-PFGE was 14 hours for each stage. Electrophoresis was performed for 22 hours, in case of XbaI, with 3 seconds of initial pulse and 12 seconds of final pulse. Electrophoresis was performed for 22 hours, in case of AsnI, with 5 seconds of initial pulse and 25 seconds of final pulse. In all cases the voltage of the electrophoresis was maintained constantly at 200 voltage. Standard mycobacterial strains, which included Mycobacterium bovis BCG, M. tuberculosis, and M. fortuitum, could not be differentiated by PFGE analysis. PFGE analysis was performed to differentiate 9 clinically isolated M. fortuitum strains using AsnI. All M. fortuitum strains showed different genotypes except 2 strains. Cluster analysis divided M. fortuitum strains into 2 large groups. PFGE analysis was performed to further differentiate M. fortuitum isolates using XbaI. The undifferentiated 2 M. fortuitum strains showed different PFGE patterns with Xba I. Cluster analysis of the XbaI-PFGE patterns showed more complex grouping than AsnI-PFGE patterns, which showed that XbaI-PFGE analysis was better than AsnI-PFGE in M. fortuitum genotyping. The top dissimilarity values of AsnI-PFGE and XbaI-PFGE were 0.74 and 0.75, respectively. This value was higher than that of arbitrarily primed polymerase chain reaction (AP-PCR) analysis and lower than that of restriction fragment length polymorphism (RFLP) analysis. This suggested that PFGE can be used as a supportive or alternative genotyping method to RFLP analysis.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.77-86
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• 2003

Pullorum disease due to Salmonella enterica subspecies enterica bioserovar Pullorum (S. pullorum) is reported to be an endemic disease in domestic poultry flocks. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of most of salmonella serotypes and other diverse bacterial species from animals and environmental samples in worldwide. Nowadays, PFGE has already been evaluated as a gold standards for molecular subtyping of salmonella serotypes compared with other molecular analysis methods. PFGE of XbaI digested chromosomal DNA from 23 strains of S. pullorum gave 5 distinctive pulsotypes (from SXPI to SXPV) with 5% confidence range of Dice coefficients, indicating that PFGE is very discriminative and that multiple clones of S. pullorum have been existed and diffused all of domestic poultry flocks industries since 1995. Two dominant pulsogroups (SXA & SXB) appeared as a major clones in this country, because they had consistently been recovered from diverse sources including both chicken organs and raw feed materials between 1995 and 1998. In addition, the matching percentage of PFGE profiles (PFP) among strains from both chickens and feed ingredients provides indirect evidence of the possible transmission of pullorum disease from contaminated raw feed ingredients for chicken production. In calculating of discrimination index (DI) for PFGE method by Simpson's index, DI was appeared as 0.917. Therefore, this index suggested that the present PFGE would seem to be a desirable and confident molecular typing method for S. pullorum strains. To our knowledge for pullorum disease, this is the first study to compare S. pullorum strains from chicken organs and feed samples using the PFGE.

• Tuberculosis and Respiratory Diseases
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• v.77 no.4
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• pp.172-177
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• 2014

Background: Pseudomonas aeruginosa infection is particularly associated with progressive and ultimately chronic recurrent respiratory infections in chronic obstructive pulmonary disease, bronchiectasis, chronic destroyed lung disease, and cystic fibrosis. Its treatment is also very complex because of drug resistance and recurrence. Methods: Forty eight cultures from 18 patients with recurrent P. aeruginosa pneumonia from 1998 to 2002 were included in this study. Two or more pairs of sputum cultures were performed during 2 or more different periods of recurrences. The comparison of strains was made according to the phenotypic patterns of antibiotic resistance and chromosomal fingerprinting by pulsed field gel electrophoresis (PFGE) using the genomic DNA of P. aeruginosa from the sputum culture. Results: Phenotypic patterns of antibiotic resistance of P. aeruginosa were not correlated with their prior antibiotic exposition. Fifteen of 18 patients (83.3%) had recurrent P. aeruginosa pneumonia caused by the strains with same PFGE pattern. Conclusion: These data suggest that the most of the recurrent P. aeruginosa infections in chronic lung disease occurred due to the relapse of prior infections. Further investigations should be performed for assessing the molecular mechanisms of the persistent colonization and for determining how to eradicate clonal persistence of P. aeruginosa.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.183-189
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• 2007

Shigellosis is the most common bacterial gastroenteritis both in developing and developed countries, but bacteremia due to Shigella spp. is very rare. In developed countries recent shigellosis is mostly caused by S. sonnei, but S. flexeri infection is rare. We had rare cases of S. flexeri infections in a family in the Jeonbuk Province: an 8-year-old boy with bacteremic shigellosis and 10- and 12-year-old brothers with diarrhea. The isolates had identical biochemical characteristics, and were resistant to ampicillin, chloramphenicol, and co-trimoxazole. PFGE pattern of Not I-restricted genomic DNA suggested that the isolate from blood was closely related to the two strains isolated from stool which had an identical PFGE pattern.

• Korean Journal of Veterinary Service
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• v.24 no.3
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• pp.243-253
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• 2001

Forty-five Salmonella typhimurium isolates were encountered 8 phage types in which DT197 and U302 were the predominant types. The DT104 type which was first found from pig in Korea, and was resistant to chloramphenicol, streptomycin, sulfamethoxazole/trimethoprim, tetracycline, gentamicin and nalidixic acid. Twenty-two S enteritidis isolates were encountered 5 phage types in which PT4 were the representative (predominant). S enteritidis isolates were susceptible to all antimicrobial agents. As a result of PFGE analysis for S typhimurium and S enteritidis, PFGE patterns was better than phage typing in discriminating of strains. PFGE patterns were not in accord with phage type even though some strain had the same phage types.

• Korean Journal of Veterinary Service
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• v.29 no.3
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• pp.297-308
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• 2006

Fowl typhoid (FT) is a septicemic disease caused by Salmonella gallinarum. The purpose of this study was to investigate the antimicrobial resistance and pulsed -field gel electrophoresis (PFGE) patterns of S gallinarum isolated from broiler. During 1999 to 2004, there was isolated a total of 26 strains in liver and spleen. The biochemical characteristics of S gallinarum isolates was nonmotile, no production of $H_2S$, glucose gas, non-fermented rhamnose, indole-negative, fermentation of dulcitol, mannitol, maltose, and ornithine decarboxylase. At antimicrobial susceptibility, all of isolates were susceptible to amoxicillin/clavulanic acid, amikacin, neomycin, kanamycin, and cephalothin. Twenty-six isolates were divided into 19 resistant patterns and 6 strains was 8-multi-drug resistance. PFGE of Xba I restriction fragments of S gallinarum isolates was 22 patterns.

• Biomedical Science Letters
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• v.11 no.2
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• pp.121-128
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• 2005

A total of 30L monocytogenes strains from different sources including 13 strains isolated from the foreign imported meat were genotyped in order to establish their genetic relatedness and to compare them with the foreign isolates. PFGE analysis of genomic DNA showed the $11\~16$ fragments ranging in size from 38 to 504 kb. Eleven different PFGE types $(1\~11)$ were identified in the dendrogram at $75\%$ similarity, and the two major PFGE types, type 1 and 2, contained $94\%$ of domestic isolates (16/17). All isolates from domestic beef and pork carcass were grouped in each different type, however, isolates from chicken were clustered together with those from pork and beef. We also found all foreign strains were unrelated with each other, regardless of geographic criteria and that they could be differentiated from those from the domestic isolates by PFGE pattern. The PFGE pattern of one isolate from chicken wing, which the chicken meat was found to be imported from foreign country, was closely related to that of isolate from the Thailand.

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.155-163
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• 2009

Fowl typhoid (FT) is a septicemic disease caused by Salmonella Gallinarum. The purpose of this study was to investigate the antimicrobial resistance and pulsed-field gel electrophoresis (PFGE) patterns of S. Gallinarum isolated from chicken. During 1999 to 2004, there was isolated a total of 100 strains in liver and spleen. The biochemical characteristics of S. Gallinarum isolates was nonmotile, no production of H$_2$S, glucose gas, non-fermented rhamnose, indole-negative, fermentation of dulcitol, mannitol, maltose, and ornithine decarboxylase. At antimicrobial susceptibility, all of isolates were susceptible to amoxicillin/clavulanic acid, amikacin, neomycin, kanamycin, norfloxacin and enrofloxacin. One hundred isolates were divided into 54 resistant patterns and 37 strains was 6-multi drug resistance. PFGE of Xba I restriction fragments of S. Gallinarum isolates was 20 patterns.

• Journal of Preventive Medicine and Public Health
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• v.45 no.1
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• pp.1-7
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• 2012

Using three Austrian case studies, the variegated applications of molecular typing in today's public health laboratories are discussed to help illustrate preventive management strategies relying on DNA subtyping. DNA macrorestriction analysis by pulsed field gel electrophoresis has become the gold standard for subtyping of food borne pathogens like listeria, salmonella, campylobacter and Bacillus cereus. Using a Salmonella Mbandaka outbreak from the year 2010 as example, it is shown how the comparison of patterns from human isolates, food isolates, animal isolates and feed isolates can allow to identify and confirm a source of disease. An epidemiological connection between the simultaneous occurrence of tuberculosis in cattle and deer with cases of human tuberculosis due to Mycobacterium caprae in 2010 was excluded using mycobacterial interspersed repetitive units variable-number tandem repeats subtyping. Also in 2010, multilocus sequence typing with nonselective housekeeping genes, the so-called sequence based typing protocol, was used to elucidate connections between an environmental source (a hospital drinking water system) and a case of legionellosis. During the last decades, molecular typing has evolved to become a routine tool in the daily work of public health laboratories. The challenge is now no longer to simply type microorganisms, but to type them in a way that allows for data exchange between public health laboratories all over the world.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.197-204
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• 1999

A total of 22 Leptospiua inlermgans field isolates from the ~ a t s captured in 5 provinces of Korea in 1996, and 6 antigenically closely related relerence serovars of lai, yeonchon, birkini. gem, mwogolo. and canicola were analysed. When the antigenic characteristics were analysed by reactivity with 7 monoclonal antibodies prepared with sh.ains belongng to serogroup Icterohaemorrhagiae. all 22 isolates showed the same reaction pattern with that of serovar lai. Large restriction fragment patterns obtained after cleavage of geno~nic DNAs with infrequently cuttimg restriction enzymes were analyzed by pulsed-field pel electrophoresis(PFGE). Identification of leptospira strains by PFGE with Nor I, Asc I or Iise I digests correlated with their antigenically typed serovars, silh a few exceptions. PFGE of isolates, except for JR89, digested wjth Nor I showed identical pattern w~th serovar lai, showing 13 Cragments between 940 kb and 63 kb. When PFGE pallerns of JR89 were compared with those of serovar lai, Not I digest showed additional two hands of 1000 kb and 460 kb, while Asc I digest showed 650 kb fragment and Fse I digest did not show the fragment of 280 kb. Whereas serovar yeonchon. which was isolated in Korea and identified as a new serovar previously. could be differentiated from serovar lai in antigenic reactivities with monoclonal antibodres. it showed the similar PFGE pattern with serovar lai includin~ reference and field isolates. It was suggested that Korean leptospiral field isolates are closely related in DNA level.