• Proceedings of the PSK Conference
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• 2002.04a
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• pp.87-88
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• 2002

• Microbiology and Biotechnology Letters
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• v.36 no.2
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• pp.101-105
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• 2008

In order to obtain yeast cells producing a bacteriocin OR-7, the 180 bp polynucleotide corresponding to the OR-7 gene including codons for start and stop was chemically synthesized and cloned into pAUR123, an yeast expression vector. Transformed yeast cells exhibited growth inhibition of Bacillus subtilis, Campylobacter jeuni, Escherichia coli and Pseudomonas aeruginosa. This result indicates that yeast cells producing OR-7 possess bacteriocidal properties against both Gram positive B. subtilis and Gram negative C. jejuni, E. coli and P. aeruginosa cells. The recombinant yeast strain constructed in this study can be applied in the food preservative or animal feed.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.490-494
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• 2011

Although bacterial outbreaks from ready-to-eat foods have increased, little information is available on microbial quality of sprouts in markets. Fifty sprouts and 30 salads were collected from wholesale markets. Total aerobic count (TAC), coliform, Escherichia coli, and some pathogens were detected. TAC for sprouts was 7.95 log CFU/g and 6.70 for salads, indicating that sprouts were more contaminated by 1 log CFU/g than that of salads. The numbers of coliform were 6.69 log CFU/g for sprouts and 5.42 for salads. E. coli was detected in 16 of 50 sprout samples at 2.38 log CFU/g and eight of 30 salads at 2.21 log CFU/g. Bacillus cereus was detected in 29 of 50 sprout samples and 16 of 30 salads, and the counts were mostly <3 log CFU/g. Salmonella, Staphylococcus aureus, Listeria monocytogenes, Campylobacter jejuni, and Clostridium perfringens were not detected. Therefore, although pathogens may not be a high risk for these foods, the high TAC and E. coli contamination require improved production and distribution methods, particularly for sprouts.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.483-488
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• 2008

Foodborne pathogenic bacteria in various food samples in Korea were monitored and the obtained data was statistically analyzed. A total of 1,240 food samples including 280 sashimi, 244 processed frozen products, 258 kimbab (cooked rice wrapped with seaweed), 337 soybean pastes were obtained from 7 cities including Seoul in Korea. Microorganisms tested were Bacillus cereus, Salmonella spp., Staphylococcus aureus, Escherichia coli, E. coli O157:H7, Vibrio parahaemolyticus, Yersinia enterocolitica, Listeria monocytogenes, Campylobacter jejuni, and Clostridium perfringens. The contaminated microorganisms in food samples were comprised of 10.55% B. cereus, 2.7% S. aureus, 2.0% V. parahaemolyticus, 0.8% C. perfringens, 0.2% Y. enterocolitica, and 0.1% of L. monocytogenes, respectively. Salmonella spp., C. jejuni, and E. coli O157:H7 were not detected in any of the food samples. Particularly, B. cereus that harbors the enterotoxin gene was detected in various foods and regions in Korea, therefore it should be a given special consideration not to allow the hazardous level of contamination.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.17-25
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• 2007

The kinds and quantity of antimicrobial agents used for cattle (animal industry) may be considerable, suggesting the possibility that pathogenic bacteria which cannot be extirpated by the existing antimicrobial agents could appear. Ten cattle, pig and chicken farms, respectively, were randomly selected from 5 provinces in Korea and the samples were collected from excrement, manure, underground water, farmers' hands and the neishboring environment. h total of 299 samples were examined and 197 of Escherichia coli, 13 of Campylobacter jejun/coli, 223 of Enterococcus faecium/faecalis and 42 of Staphylococcus aureus isolates were collected. All isolates were screened for antimicrobial resistance: 69.4% of E. coli (137/197 strains), 78.6% of S. aureus (33/42 strains), and 82.1% of E. faecium/faecalis (183/223 strains) were resistant to one antimicrobial agent and all of C. jejuni/coli Isolates showed the resistance to one antimicrobial agent. Meanwhile, the multiple resistance ratio for more than 4 lines of antimicrobial agent was 19.2% of E. coli (38/197 strains), 11.9% of S. aureus (5/42 strains), 15.4% of C. jejuni/coli (2/13 strains) and 6.2% of E. faecium/faecalis (14/223 strains). The antimicrobial resistance ratio of bacteria isolated from the cattle farm showed lower than that of bacteria isolated from the pig or chicken farm, which might be related to the quantify of antimicrobial agents consumed. And one strain of vancomycin resistant E..faecium (VREF) were isolated from the excrement of chicken and stream, respectively. Generally, the ratio of VREF collected in animal farm environments is lower than that of VREF collected in medical environment.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.625-630
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• 1995

α-Linked D-altropyranosidic derivatives were obtained by configurational change at C-3 of α-D-mannopyranosides as the key step in preparation of allyl and methyl α-D-glycopyranosides of 6-deoxy-D-altro-heptose. The manno-altro conversion was effected by sequential reactions of Swern oxidation and stereoselective borohydride reduction. Allyl 4,6-O-benzylidene-2-O-p-methoxybenzyl-α-D-mannopyranoside was transformed to the corresponding altropyranoside via 3-oxo-arabino-hexopyranoside. Allyl 7-O-benzyl-6-deoxy-3,4-O-isopropylidene-α-D-altro-heptopyranoside has been prepared as a glycosyl acceptor to be coupled with β-D-GlcpNAc-(1→3)-α-D-Galp glycosyl donor for the synthesis of an O-antigen repeating unit of Campylobacter jejuni serotypes O:23 and O:36. Stereoselective borohydride reduction also succeeded in yielding methyl 2,4,7-tri-O-benzyl-6-deoxy-α-D-altro-heptopyranoside from the corresponding 3-oxo-α-D-arabino-heptopyranoside. C-6 Homologation was achieved by sequential reactions of cyanide displacement of 6-sulphonates, reduction of the resulting heptopyranosidurononitrile with diisobutylaluminum hydride, hydrolysis of the imine, and further reduction with sodium borohydride.

• Food Science and Preservation
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• v.16 no.6
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• pp.965-970
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• 2009

PCR technology has been widely used to detect and quantify microbial pathogens in foodstuffs, because the technique is rapid, sensitive, and selective. In this study, detection of contaminating pathogenic bacteria on shells of chicken eggs was performed using both a commercial multiplex polymerase chain reaction (PCR) kit and a viable count method employing a selective medium. The PCR kit was capable of detecting Campylobacter jejuni, Escherichia coli O157:H7, Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Salmonella species, and Shigella species. Using the PCR method, five bacterial species were detected from 30 samples (33.3%) of 90 batches of eggs commercially available in a market. PCR products from B. cereus, S. aureus, L. monocytogenes, Y. enterocolitica, and E. coli O157:H7 were detected, and the numbers and frequencies of positive samples were 17 (18.8%), 12 (13.3%), 15 (16.6%), 16 (17.7%),and 4 (4.4%), respectively. None of any Salmonella species, C. jejuni, V. parahaemolyticus, or Shigella species was detected in this study. The results of PCR testing were confirmed using a typical viable count method employing a selective medium. We suggest that the multiplex polymerase chain reaction (mPCR) assay is a rapid and reliable method for detection of pathogenic bacteria contaminating eggs.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.125-128
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• 2005

A 16S ribosomal RNA gene from S. chungbukensis DJ77 has been sequenced. This sequence had a length of 1,502 bp and was extended for 29 bp at 5' and for 37 bp at 3' from the partial sequence (1,435 bp) registered in 2000 year. Besides, 1 bp was newly added near to the 3' end. We made the secondary structure of the 16S rRNA based on E. coli model and found four specific regions. We found constant and variable regions in genus Sphingomonas as the result of multiple alignment of 16S rRNA gene sequences from Sphingomonas spp. and S. chungbukensis DJ77. We found a stem loop structure in S. chungbukensis DJ77, which was only discovered in C. jejuni to date. It showed the structural agreement despite the difference of the sequences from the both organisms. Finally, S. chungbukensis DJ77 belonged to cluster II (Sphingobium) group, after the classification using phylogenetic analysis and nucleotide signature analysis.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.941-947
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• 2005

The contamination frequency of major foodborne pathogenic bacteria was investigated from 213 seafood samples including sliced raw fish and shellfish in Busan and CyeongNam province area. Tested microorganisms were Salmonella spp. Staphyloroccus aureus, Vibrio parahaemolyticus, Escherichia coli O157:H7, Bncillus cereus, Listeria monocytogenes and Campylobacter jejuni. The frequency of isolated microorganisms was V. parahaemolyticus (30.5%), B. cereus (9.9%), S. aureus (3.8%) and other pathogenic bacteria (1.4%). from July to October, total isolation rates were greater than 50% and V. parahaemolyticus was dominant among the microorganisms isolated. The bacteria isolation rate (49.2%) in raw seafoods including shellfishes was higher than one (28.9%) in sliced raw fish. V. parahaemelyticus isolates were resistant to ampicillin (96.9%), amikacin (29.2%) and tetracycline (27.7%), and B. cereus isolates were resistant to ampicillin (100%), Penicillin G (100%), rifampicin (71.4%) and tetracycline (14.3%). The growth of V. parahaemolyticus and B. rereus was greatly inhibited below $10^{\circ}C$, but increased at ambient temperature. Washing seafood with tap water showed to reduce total count of remaining V. parahaemolyticus. Thus temperature control under $10^{\circ}C$, sufficient washing and prompt eating appeared to reduce the risk of food poisoning by these bacteria in seafoods.

• Molecules and Cells
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• v.25 no.1
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• pp.138-141
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• 2008

HP0892 (SwissProt/TrEMBL ID O25552) is a 90-residue conserved hypothetical protein from Helicobacter pylori strain 26695, with a calculated pI of 9.38 and a molecular mass of 10.41 kDa. It belongs to the Plasmid stabilization system protein family (PF05016) in the Pfam database. Proteins with sequence similarity to HP0892 exist in Vibrio choierae, Enterococcus faecalis, Campylobacter jejuni, Streptococcus pneumoniae, Haemophilus influenzae, Escherichia coli O157. Here we report the sequence-specific backbone resonance assignments of HP0892 using multidimentional heteronuclear NMR spectroscopy. About 97.0% (422/435) of the HN, N, CO, $C{\beta}$, $C{\alpha}$ resonances of 90 residues of HP0892 were assigned. On the basis of the resonance assignments, three helical regions and four strand regions were identified using the CSI program. This study is a prerequisite for calculating the solution structure of HP0892, and will be useful for studying its interaction with other molecules.