• 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.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1301-1305
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• 2006

The development of rapid, infallible, and sensitive methods of detecting foodborne pathogens has received much impetus in recent years owing to an increased public awareness of the health hazards. For the rapid and simultaneous detection of these foodborne pathogens, a multiplex PCR method was developed. Yersinia enterocolitica, Staphylococcus aureus, and Shigella spp. are bacteria of concern because of their specific growing condition that enables them to live at low temperatures. In order to detect each pathogenic bacterium, specific primers from Y. enterocolitica, St. aureus, and Sh. flexneri were selected and validated successfully. To apply this method to food stored at low temperature, Y. enterocolitica, St. aureus, and Sh. flexneri were artificially inoculated in lettuce and incubated for enrichment. The multiplex PCR assays were able to simultaneously detect three pathogens, and the presence of three bands was observed at initial inoculation levels of approximately 1$\times$10$^1$ CFU/g in lettuce. Therefore, this method could be used for simultaneous detection of Y. enterocolitica, St. aureus, and Shigella spp. contaminated in lettuce during cultivation, transportation, preservation, and storage.

• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.610-615
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• 2017

When Shigella infect host cells, various effecter molecules are delivered into the cytoplasm of the host cell through the type III secretion system (TTSS) to facilitate their invasion process and control the host immune responses. Among these effectors, the S. flexneri effector OspF dephosphorylates mitogen-activated protein kinases and translocates itself to the nucleus, thus preventing histone H3 modification to regulate expression of proinflammatory cytokines. Despite the critical role of OspF, the mechanism by which it localizes in the nucleus has remained to be elucidated. In the present study, we identified a potential small ubiquitin-related modifier (SUMO) modification site within OspF and we demonstrated that Shigella TTSS effector OspF is conjugated with SUMO in the host cell and this modification mediates the nuclear translocation of OspF. Our results show a bacterial virulence factor can exploit host post-translational machinery to execute its intracellular trafficking.

• Journal of Nutrition and Health
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• v.37 no.8
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• pp.655-661
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• 2004

This study was performed to investigate the antimicrobial effect of the Pulsatilla koreana extracts against food-borne pathogens. First, the Pulsatilla koreana was extracted with methanol at room temperatures, and fractionation of the methanol extracts from Pulsatilla koreana was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol respectively. The antimicrobial activity of the Pulsatilla koreana extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Pulsatilla koreana showed the highest antimicrobial activity against Staphylococcus aureus, Salmonella enteritidis and Shigella dysenteriae. The Staphylococcus aureus and Shigella dysenteriae were inhibited by petroleum ether and chloroform extracts of Pulsatilla koreana as well as ethyl acetate extracts of Pulsatilla koreana. The synergistic effect has been found in combined extracts of Pulsatilla koreana and Portulaca oleracea as compared to each extracts alone. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Pulsatilla koreana against Staphylococcus aureus and Shigella dysenteriae. The ethyl acetate extract of Pulsatilla koreana showed strong antimicrobial activity against Staphylococcus aureus at the concentration of 2,000 ppm. The 2,000 ppm of ethyl acetate extract from Pulsatilla koreana retarded the growth of S. aureus more than 12 hours and Shigella dysenteriae up to 9 hours.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.2
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• pp.182-187
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• 2005

This study was performed to investigate the antimicrobial effect of the Viscum album var. coloratum extracts against food-borne pathogens. First, the Viscum album var. coloratum was extracted with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol, respectively. The antimicrobial activity of the Viscum album var. coloratum extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The petroleum ether extracts of Viscum album var. coloratum showed the highest antimicrobial activity against Bacillus cereus and Shigella dysenteriae. Synergistic effect in inhibition was observed when Viscum album var. coloratum extract was mixed with Perillae folium extract as compared with each extract alone. Finally, the growth inhibition curves were determined by using petroleum ether extracts of Viscum album var. coloratum against Bacillus cereus and Shigella dysenteriae. The petroleum ether extract of Viscum album var. coloratum had strong antimicrobial activity against Bacillus cereus at the concentration of 5,000 ppm. At this concentration, the growth of Bacillus cereus was retarded more than 24 hours and up to 12 hours for Shigella dysenteriae. In conclusion, the petroleum ether extracts of Viscum album var. coloratum inhibit efficiently Bacillus cereus and Shigella dysenteriae.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.33-38
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• 1980

Shigella remains to be an important enteric pathogen in this country for the moment. Moreover, since 1978, most of the isolates have become resistant to ampicillin and co-trimoxazole, which used to be the drugs of choice for shigellosis. Since a disc diffusion technique alone has been used in our routine susceptibility test, the minimum inhibitory concentrations(MIC) of both ampicillin and co-trimoxazole to Shigella have never been known. In order to determine these, 195 isolates were tested by an agar dilution method, all of which were isolated at Yonsei Medical Center during the period of June 1978 to July 1980. The following results were obtained. 1. Sixty cultures(29.7%) were susceptible to ampicillin, being the MIC of 8 ${\mu}g/ml$ or less and 53(27.2%) were susceptible to co-trimoxazole, being the MIC of TMP/SMZ 4/76 ${\mu}g/ml$ or less. S. flexneri type 2 was often resistant to both antimicrobic agents. 2. An increasing rate of resistant isolates was noted, particularly in the year of 1979. 3. Many isolates were resistant to both agents. Somewhat more cultures. were ampicillin susceptible and co-trimoxazole resistant than the other way around. It seems that the determination of species or even serotypes might be of help sometimes to select proper antimicrobic agent to control the infection. A routine antimicrobic susceptibility test of Shigella to both ampicillin and co-trimoxazole would be advisable for a better selection of chemotherapeutic agent.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.31-36
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• 1978

Twenty strains of Salmonella paratyphi A, 55 of S. typhi, 7 of Shigella flexneri, and 14 of Sh. sonnei which were isolated in Taegu area in 1977, were tested for the susceptibility to antimicrobial drugs. All strains of S. paratyphi A were resistant to sulfisomidine(Sa), but none was resistant to chloramphenical(Cm), tetracycline(Tc), streptomycin(Sm), ampicillin, nalidixic acid, kanamycin, gentamicin, amikacin, 1:20 mixture of trimethoprim and sulfamethoxazole, carbenicillin, cephaloridine, and rifampicin. Only one strain. of S. typhi was multiply resistant to Cm, Tc, Sm, and Sa, but all strains were susceptible to the other drugs tested. The resistant strain carried R plasmid; R(Cm Tc Sm Sa). All strains except one were highly resistant to Cm, Tc, Sm, and Sa, and all except one of multiply resistant strains carried R plasmid; R(Cm Tc Sm Sa).

• The Journal of the Korean Society for Microbiology
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• v.14 no.1
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• pp.27-37
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• 1979

Ninety-five strains of Shigella, 70 of Salmonella paratyphi A, and 230 of Salmonella typhi were tested for their resistance to drugs. Also studied was the inhibition and elimination of drug resistance. All except one strain of Shigella consisted of 79 Sh. flexneri and 16 Sh. sonnei were multiply resistant to chloramphenicol, tetracycline, streptomycin, and splfisomidine. Among them, 70 strains were resistant to ampicillin and carbenicillin, 80 to trimethoprim-sulfamethoxazole, 22 to nalidixic acid, and one to kanamycin, but strain resistant to gentamicin, cephaloridine, and rifampin was not encountered. All strains of S. paratyphi A and S. typhi were susceptible to drugs tested, except sulfisomidine and rifampin, for which all S. paratyphi A were slightly resistant to sulfisomidine and the majority of S. paratyphi A and S. typhi were slightly resistant to rifampin. Approximately 80% of multiply drug-resistant Shigella transferred their resistance to E. coli by conjugation, and the resistance was considered to be mediated by R plasmids. The frequency of transfer of drug resistance varied by donor strains and recipients, but not by selecting drugs. Resistance to nalidixic acid was not transferred by conjugation to the recipients. Drug-resistant Shigella strains successively subcultured in nutrient agar stabs contained clones resistant to drugs and those susceptible to drugs, but the ratio of resistant and susceptible clones varied by strains. The multiply drug-resistant S. typhi and Shigella strains were found to not lose completely their drug resistance by subculture in media. Acriflavine has some effect on the elimination of drug resistance mediated by R plasmids, but the effect varied markedly by strains. Atabrine has no effect among strains tested. The combination of drugs increased the drug actions in majority of cases with synergistic or additive effects.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2224-2227
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• 2016

Shigella sonnei harboring $bla_{CTX-M-55}$ was isolated outside of Asia for the first time. The $bla_{CTX-M-55}$ gene was found to be downstream of ISEcp-1 and located in a ~130 kb conjugative plasmid belonging to the I1 incompatibility group. The strain was recovered from a 7-year-old Ecuadorian girl with watery diarrhea who had not travelled abroad. Recent local data describe the emergence of $bla_{CTX-M-55}$ and other variants typically found in Asia in the Andean Region, suggesting that increased travel of humans and trade relationships with Asian countries are influencing the current Ecuadorian bacterial resistance situation.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.306-311
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• 2004

This study was performed to investigate the antimicrobial effects of Portulaca oleracea extracts against food-borne pathogens. First, the Portulaca oleracea was extracted with methanol at room temperature, and then further fractionated by using petroleum ether, chloroform, ethyl acetate and methanol, respectively. The antimicrobial activity of the Portulaca oleracea extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Portulaca oleracea showed the highest antimicrobial activity against Staphylococcus aureus and Shigella dysenteriae. There was also a synergistic effect of the combined extracts of Portulaca oleracea and Indigofera kirilowii as compared to each extract alone. Finally, the growth inhibition curve of ethyl acetate extracts of Portulaca oleracea against Staph­ylococcus aureus and Shigella dysenteriae was determined The ethyl acetate extract of Portulaca oleracea showed strong antimicrobial activity against Staphylococcus aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate extract from Portulaca oleracea, retarded the growth of S. aureus by more than 24 hand Shigella dysenteriae up to 12 h at $37^{\circ}C$.