• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.75.1-75
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• 2003

Barely yellow mosaic(BaYMV) and barely mild mosaic (BaMMV) bymoviruses are both transmitted by the soil-inhabiting fungus Polymyxa gramnis, and are responsible for economic losses in barley crops in Asia and Europe. Because chemical control of the vector is ineffective, the losses can only be prevented by growing resistant barley cultivars. The objective of this study is to produce resistant barley plants by transformation with viral coat protein(cp) genes. Resistance tests of T1 plants transformed with the BaYMV CP gene showed that at least four independent lines had clear resistance to BaYMV but two other lines were highly susceptible with severe symptoms. The CP gene was detected in all resistant T1 plants by genomic PCR. Most of T2 progenies derived from the resistant T1 lines also showed resistance. In contrast, only one out of 21 independent T2 lines transformed with the BAMMV CP gene tested showed clear resistance to BaMMV, and others were very susceptible. Further analyses of resistance and CP gene expression are in progress.

• Journal of Food Hygiene and Safety
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• v.18 no.2
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• pp.79-86
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• 2003

Most of food poisoning is frequently raised from mass catering. Especially, staphylococci takes the large part of pathogenic agents which are related to the hygienic condition. Among total 98 samples, four staphylococci were isolated from food service environment such as drinking water (A), hands (D), refrigerator and apron (E) of 5 elementary school (A, B, C, D, E) in Gyeongnam Province. These isolated strains are characterized as 1 MRCNS (Methicilline Resistant Coagulase Negative Staphylococcus aureus) and 3 MSCPS (Methicilline Sensitive Coagulase positive Staphylococcus aureus). Also, production of enterotoxin B (sob gene) were examined by PCR which has known as a big problem because of their temperature resistance. Hence, PCR was performed on isolated 4 staphylococci. The all 4 isolated Staphylococcus aureus have 477 bp of seb gene. Antibiotics susceptibility test was completed on PCR detected strains. All strains were fully resistance to ampicillin and penicillin. The drinking water of A place has resistance to oxacilline, therefore this strain turned out to be MRSA (Methicilline Resistant Staphylococcus Aureus).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.913-915
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• 2012

RNA polymerase beta subunit gene (rpoB) mutation of rifampin-resistant Mycobacteria was analyzed using nucleotide sequence of rpoB DNA (351 bp) containing rifampin resistant region, $rif^r$. For this purpose, we collected rifampin-resistant Mycobacteria that were identified by conventional culture method from Masan National Hospital and The Korean Institute of Tuberculosis and performed analysis of nucleotide sequence of rpoB of them. We found various mutations of rpoB linked rifampin resistant gene from rifampin-resistant Mycobacteria. From this study, we identified mutations of different codons from codons that have been reported recently.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.2
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• pp.68-74
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• 2011

Pseudomonas aeruginosa is an aerobic, Gram-negative, glucose-nonfermenting bacterium, which has emerged as a serious opportunistic pathogen. Recently, outbreaks of carbapenem resistant P. aeruginosa give rise to significant therapeutic challenges for treating nosocomial infections. The genes of metallo-${\beta}$-lactamase (MBL), a powerful carbapenemase, are carried as a part of the mobile gene cassettes inserted into integrons playing an important role in rapid dissemination of antibiotic resistance genes among bacterial isolates. In this study, we investigated the prevalence of integron in imipenem resistant P. aeruginosa isolates. A total of 61 consecutive, non-duplicate, and imipenem resistant P. aeruginosa strains were isolated from a university hospital in the Chungcheong province of Korea. We employed repetitive extragenic palindromic sequence-based PCR (rep-PCR) method for the selection of clonally different P. aerusinosa strains. PCR and DNA sequencing were conducted for the detection of integrons. Twenty-one clonally different P. aeruginosa strains were isolated. Only one (P28) of the strains harbored $bla_{VIM-2}$ that was found as gene cassettes in class 1 integrons. Four of 21 carbapenem resistant P. aeruginosa strains harbored class 1 integron containing aminoglycoside resistance determinant. All of the integrons detected in the study contained more than one resistance gene cassette, which can mediate resistance to multiple antibiotics. To prevent further spreading of the multi-drug resistant P. aeruginosa, conseguent monitoring and clinical polices are required.

• Korean Journal of Veterinary Service
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• v.40 no.1
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• pp.41-46
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• 2017

The purpose of this study was to investigated the fluoroquinolone (FQ) resistance and presence of gyrA and grlA gene in 87 Staphylococcus pseudintermedius isolates obtained from clinical samples of dogs and cats. Also, the profiles of FQ resistance compared with methicillin resistant S. pseudintermedius (MRSP) isolates. FQ resistance was observed for enrofloxacin (41.4%), ciprofloxacin (39.1%), norfloxacin (36.8%), ofloxacin and levofloxacin (32.2%, respectively), and moxifloxacin (31.0%). Thirty-eight (43.7%) of 87 S. pseudintermedius isolates were resistant to more than one FQ. Twenty-six (64.5%) of 38 FQ resistant isolates were resistant to all the six FQ tested. Of 38 FQ resistant isolates, gyrA gene was detected in all isolates but grlA gene was not found. Moreover, 19 MRSP isolates were resistant to enrofloxacin (63.2%), ciprofloxacin (57.9%), norfloxacin (52.6%), and ofloxacin, levofloxacin and moxifloxacin (47.4%, respectively). FQ resistance were highly prevalence in S. pseudintermedius isolates from dogs and cats. Our results emphasize the prudent use of antimicrobial agents to companion animals is necessary for prevent antimicrobial resistance.

• Molecules and Cells
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• v.20 no.1
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• pp.30-34
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• 2005

This study was carried out to identify a high-resolution marker for a gene conferring resistance to brown planthopper (BPH) biotype 1, using japonica type resistant lines. Bulked segregant analyses were conducted using 520 RAPD primers to identify RAPD fragments linked to the BPH resistance gene. Eleven RAPDs were shown to be polymorphic amplicons between resistant and susceptible progeny. One of these primers, OPE 18, which amplified a 923 bp band tightly linked to resistance, was converted into a sequence-tagged-site (STS) marker. The STS marker, BpE18-3, was easily detectable as a dominant band with tight linkage (3.9cM) to Bph1. It promises to be useful as a marker for assisted selection of resistant progeny in backcross breeding programs to introgress the resistance gene into elite japonica cultivars.

• Pediatric Infection and Vaccine
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• v.3 no.2
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• pp.133-138
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• 1996

Purpose : In the treatment of MRSA infection, rapid detection of MRSA is extremely important. The mecA gene codes the new drug resistant polypeptides called PBP2' which mediates the clinically relevant resistance to all beta-lactam antibiotics. The identical mecA gene has been found in coagulase-negative staphylococcus with the methicillin-resistant phenotype. On the other hand, the femA gene was absent from coagulase negative staphylococcus strains with the methicillin resistant phenotype. This study is aimed at early detection and definite diagnosis of MRSA. Methods : A total of 24 MRSA strains were studied. All strains were tested for antimicrobial susceptibility and purified DNA. We amplified both mecA and femA genes by PCR in 24 strains. Results : In MRSA all the 16 strains (100%) carried femA gene and 11 strains (68.7%) carried mecA gene. In contrast, in methicillin sensitive staphylococcus all the 8 strains (100%) carried femA and only 3 strains (37.5%) were detected mecA. Conclusions : As results, there are difference in the phenotype and genotype of methicillin resistance by PCR of mecA and femA. Such disparities between methicillin resistance and the presence of mecA gene suggest the presence of control gene of the mecA.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.133-138
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• 2013

In this study, a total of 256 samples of retail raw meats (beef, pork and chicken) and sashimi were investigated for the presence of Enterococcus faecalis and Enterococcus faecium. We isolated a total of 117 E. faecalis and E. faecium from the samples, with contamination rates ranging from 18.8% for sashimi samples to 68.8% of chicken samples. E. faecalis was the predominant species recovered from all of the retail raw meats beef (42.2%), pork (42.2%), chicken (65.6%) and sashimi (12.5%). Among 117 isolates, 61 isolates (52.1%) were resistant to tetracycline, 32 isolates (27.4%) were resistant to erythromycin, 23 isolates (19.7%) were resistant to chloramphenicol, 16 isolates (13.7%) were resistant to ripampin, 10 isolates (8.5%) were resistant to gentamycin, 9 isolates (7.7%) were resistant to ciprofloxacin and 1 isolate (0.9%) was resistant to ampicillin and penicillin G. No resistance to amoxicillin + clavulanic acid and vancomycin was observed. Although no strain was resistant to vancomycin, the vanB gene was observed in 9 of 117 of Enterococcus (7.7%) demonstrating potential risk of vancomycin-resistant Enterococcus (VRE). Our results indicate that E. faecalis and E. faecium were highly prevalent in retail raw meats, but most strains were sensitive to tested antibiotics.

• Journal of Ginseng Research
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• v.27 no.1
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• pp.37-42
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• 2003

For study about introduce of gene connected with disease and transformation system of gingseng, chitinase gene cloned from soybene and disease resistant gene were carried out for expression and transformation of plant using Agrobacterium. The disease resistance gene(DR-49), 35S-35S-AMV, has been constructed. The disease resistance gene and chitinase gene were introduced into the binary vector pRD 400, which were mobilized into Agrobacterium tumefaciens faciens strain MP 90 and LBA 4404 harboring disarmed Ti-plasmid. As a result of induce transformants using ginseng embryo and petiole, multi shoots were formed on MS medium supplemented 1 mg/ι 2,4-D and 0.5 mg/ι kinetin. Also transformation by cotyledonwas effective on MS medium supplemented 1 mg/ι 2,4-D and 0.5 mg/ι kinetin, transformation percent of disease resistant gene and chitinase gene were showed 18%, 14% respectively. As transformed tissue is under pre-embryoid condition, normal shoot is required through the process of matured embryo.

• BMB Reports
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• v.38 no.1
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• pp.89-96
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• 2005

Earlier, we reported that the bacteriophage $\lambda$ P gene product is lethal to Escherichia coli, and the E. coli rpl mutants are resistant to this $\lambda$ P gene-mediated lethality. In this paper, we show that under the $\lambda$ P gene-mediated lethal condition, the host DNA synthesis is inhibited at the initiation step. The rpl8 mutation maps around the 83 min position in the E. coli chromosome and is 94% linked with the dnaA gene. The rpl8 mutant gene has been cloned in a plasmid. This plasmid clone can protect the wild-type E. coli from $\lambda$ P gene-mediated killing and complements E. coli dnaAts46 at $42^{\circ}C$. Also, starting with the wild-type dnaA gene in a plasmid, the rpl-like mutations have been isolated by in vitro mutagenesis. DNA sequencing data show that each of the rpl8, rpl12 and rpl14 mutations has changed a single base in the dnaA gene, which translates into the amino acid changes N313T, Y200N, and S246T respectively within the DnaA protein. These results have led us to conclude that the rpl mutations, which make E. coli resistant to $\lambda$ P gene-mediated host lethality, are located within the DNA initiator gene dnaA of the host.