• 식물병연구
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• 제13권1호
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• pp.1-5
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• 2007

경상북도 북부지역 7개 시 군의 담배재배 농가를 대상으로 병해 발생상황과 농민들의 병해방제법과 관련된 재배방법을 조사하였다. 육묘기와 본밭초기의 담배에서 발생되는 전염성 병해는 극히 미미하였으며, 수확기의 담배에 가장 피해를 주는 병은 감자바이러스 Y에 의한 모자이크병과 세균성마름병(Ralstonia solanacearum)이었다. 담배모자이크바이러스(TMV)에 의한 모자이크병은 저항성 품종의 확대 보급으로 인하여 10년 전에 비하여 크게 감소되었으며, 세균성마름병 발생은 감수성 품종 보급으로 인하여 증가하였다. 30% 이상의 담배 재배 농민들이 농약을 오용하고 있었으며, 같은 수의 농민들이 10년 이상 담배를 연작하고 잘못된 윤작 작물을 선택하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.217-222
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• 2004

As Agrobacterium tumefaciens, which has long been used to transform plants, is known to transfer T-DNA to budding yeast, Saccharomyces cerevisiae, a variety of fungi were subjected to the A. tumefaciens-mediated transformation to improve their transformation frequency and feasibility. The A. tumefaciens-mediated transformation of chestnut blight fungus, Cryphonectria parasitica, is performed in this study as the first example of transformation of a hardwood fungal pathogen. The transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator, as a selectable marker, led to the selection of more than 1,000 stable, hygromycin B-resistant transformants per 1${\times}$10$\^$6/ conidia of C. parasitica. The putative transformants appeared to be mitotically stable. The transformation efficiency appears to depend on the bacterial strain, age of the bacteria cell culture and ratio of fungal spores to bacterial cells. PCR and Southern blot analysis indicated that the marker gene was inserted at different chromosomal sites. Moreover, three transformants out of ten showed more than two hybridizing bands, suggesting more than two copies of the inserted marker gene are not uncommon.

• 식품보건융합연구
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• 제6권5호
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• pp.1-10
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• 2020

Cellulitis in broiler chickens is one of the economically important problems that facing the broiler industry due to the presence of the lesion leads to condemnation of part of /or the entire carcasses. Broiler with cellulitis lesions showed lower body weight. Cellulitis was recorded on different body regions including the head, dorsum, thighs, breast, legs, and abdomen. Cellulitis results from the invasion of subcutaneous (s.c.) tissues by bacteria through disruption of skin integrity. Lesions revealed the existence of the characteristic s.c colored exudate varies from yellowish to green, which were either serosanguineous, fibrinous s.c exudate yellowish, greenish or suppurative. Many bacterial isolates including E. coli, Staphylococci, Clostridia, Aeromonas spp., Enterobacter spp., Proteus mirabilis, P. aeruginosa, and Streptococci were isolated from the lesion. Chickens exposed to immunosuppression proved to have a greater probability of developing cellulitis. The condition was experimentally induced by s.c inoculation of 25-day-old broiler chickens with E. coli, S. aureus and clostridia. Usually, bacterial isolates were multidrug-resistant. The usage of Bifidobacterium bifidum or antibiotic with avoiding immunosuppression can reduce lesion and condemnation rate resulted from cellulitis. The objective of this review is to collect different literature written about cellulitis to be available to students, researchers, and veterinarians in poultry practical.

• 한국식물병리학회지
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• 제14권2호
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• pp.177-183
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• 1998

A DNA fragment which is involved in tolassin production was cloned to obtain a molecular marker of Pseudomonas tolaasii, a casual agent of bacterial brown blotch disease of oyster mushroom (Pleurotus ostreatus). Tolaasin is a lipodepsipeptide toxin and known as a primary disease determinant of the P. tolaasii. It is responsible for formation of white line in agar when P. tolaasii were cultured against white line reacting organisms (WLROs). White line negative mutants (WL-) were generated by conjugation between rifampicin resistant strain of P. tolaasii and E. coli carrying suicidal plasmid pSUP2021 : : Tn5. The ability of tolaasin production of the WL- mutants was examined by hemolysis test, pathogenicity test, and high pressure liquid chromatography (HPLC) analysis of culture filtrate. All of the WL- mutants were lost the ability of tolaasin production (Tol-). Genomic library of the Tol- mutant was constructed in pLAFR3 and the cosmid clone containing Tn5 was selected. DNA fragment fro franking region of Tn5 was cloned from the plasmid and used as a probe in Southern blot. DNA-DNA hybridization with the probe to total DNA from group of bacteria ecologically similar to P. tolaasii including WLORs, fluorescent Pseudomonads isolated from oyster mushroom, P. agarici, P. gingeri, and some of other species of Psedomonas showed that some of the tested bacteria do not have any hybridized band and others have bands sowing RFLP. The cloned DNA fragment or its nucleotide sequence will be useful in detection and identification of the P. tolaasii.

• The Plant Pathology Journal
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• 제36권3호
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• pp.204-217
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• 2020

In nature, plants are always under the threat of pests and diseases. Pathogenic bacteria are one of the major pathogen types to cause diseases in diverse plants, resulting in negative effects on plant growth and crop yield. Chemical bactericides and antibiotics have been used as major approaches for controlling bacterial plant diseases in the field or greenhouse. However, the appearance of resistant bacteria to common antibiotics and bactericides as well as their potential negative effects on environment and human health demands bacteriologists to develop alternative control agents. Bacteriophages, the viruses that can infect and kill only target bacteria very specifically, have been demonstrated as potential agents, which may have no negative effects on environment and human health. Many bacteriophages have been isolated against diverse plant-pathogenic bacteria, and many studies have shown to efficiently manage the disease development in both controlled and open conditions such as greenhouse and field. Moreover, the specificity of bacteriophages to certain bacterial species has been applied to develop detection tools for the diagnosis of plant-pathogenic bacteria. In this paper, we summarize the promising results from greenhouse or field experiments with bacteriophages to manage diseases caused by plant-pathogenic bacteria. In addition, we summarize the usage of bacteriophages for the specific detection of plant-pathogenic bacteria.

• 한국임상수의학회지
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• 제34권1호
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• pp.23-26
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• 2017

Otitis externa (OE) is an inflammatory disease of the externa auditory meatus that occurs commonly in dogs. Antimicrobial susceptibility tests should be performed in case of chronic OE for successful treatment. In this study, identification and antimicrobial susceptibility test of bacteria isolated from dogs with chronic OE was performed. From 60 dogs with chronic OE, 60 bacterial species were identified. The most frequently identified species were Staphylococcus spp. (51%), followed by Pseudomonas spp. (15%) and Enterococcus spp. (14%). A single bacterial infection and multiple bacterial infections were observed in 67.5% and 32.5%, respectively. Staphylococcus spp. was susceptible to imipenum. Pseudomonas spp. was found to be susceptible to amikacin, cefepime, imipenum and piperacillin-tazobactam. Enterococcus spp. was susceptible to ampicillin-sulbactam, imipenum and piperacillin-tazobactam. Imipenum was highly susceptible antibiotic against both Gram-positive and negative bacteria whereas aztreonam and vancomycin were highly resistant. These results could suggest the optimal choice of antimicrobial agents for canine OE treatment.

• 미생물학회지
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• 제53권4호
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• pp.340-341
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• 2017

Acidovorax citrulli 병원세균은 수박에 과실썩음병을 일으킨다. 이 논문에서는 A. citrulli strain KACC17005 균주의 완전한 게놈 서열을 분석하여 보고한다. 게놈은 총 5,349,924 bp로 구성되어 있으며 G + C 함량이 68.54%이다. 단백질을 coding하는 유전자가 총 4,520개이고, 이들 중 적어도 15개의 유전자들은 감수성 식물에서 병원성을 증가시키거나 저항성 식물에서 면역반응을 유도하는데 중요한 제3형 effector 단백질을 코딩하고 있다.

• 대한의생명과학회지
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• 제11권4호
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• pp.525-531
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• 2005

Staphylococcus aureus is a major cause of nosocomial infections and is one of the most commonly isolated bacterial species in the hospital and continues to be an important pathogen in both community and hospital-acquired infection. Methicillin resistant S. aureus (MRSA), which is associated with hospitals is now being isolated in the community. The purpose of this study is to investigate the carrier rate of S. aureus in the community, antibiotic resistance patterns of the organism, detection of MRSA and mecA gene in MRSA. Ninety strains $(46.4\%)$ of S. aureus were isolated from the nasal specimens of 194 elementary school students. Eighty-nine strains $(98.9\%)$ of 90 S. aureus were resistant to penicilin, 36 strains $(40.0\%)$ to erythromycin, 14 strains $(15.6\%)$ to fusidic acid, 11 strains $(12.2\%)$ to gentamycin, 9 strains $(10.0\%)$ to tobramycin, 5 strains $(5.6\%)$ to oxacillin, 4 strains $(4.4\%)$ to clindamycin, 2 strains $(2.2\%)$ to tetracycline, 1 strains $(1.1\%)$ to fosfomycin. None of $90(0\%)$ S. aureus isolates was resistant to ciprpfloxacin, trimethoprim/sulfamethoxazole, levofloxacin, linezolid, moxifloxacin, nitrofurantoin, norfloxacin, rifampicin, quinupristin/dalfopristin, teicoplanin, and vancomycin. Five strains $(5.6\%)$ of 90 S. aureus isolates were MRSA. The mecA gene was detected from five MRSA strains by PCR.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1007-1014
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• 2015

Plectasin, the first defensin extracted from a fungus (the saprophytic ascomycete Pseudoplectania nigrella), is attractive as a prospective antimicrobial agent. The purpose of this study was to establish a bacterium-based production system and evaluate the antimicrobial activity of the resulting plectasin. A gene encoding plectasin, with the codon preference of Escherichia coli, was optimized based on its amino acid sequence, synthesized using genesplicing with overlap extension PCR, and inserted into the expression vector pGEX-4T-1. The fusion protein was expressed in the soluble fraction of E. coli and purified using glutathione Stransferase affinity chromatography. Plectasin was cleaved from the fusion protein with thrombin and purified by ultrafiltration. The purified plectasin showed strong, concentrationdependent antimicrobial activity against gram-positive bacteria, including antibiotic-resistant bacteria, especially penicillin-resistant Enterococcus faecium. This antimicrobial activity was equal to chemically synthesized plectasin and was maintained over a wide range of pH and temperatures. This soluble recombinant expression system in E. coli is effective for producing plectasin at a relatively lower cost, and higher purity and efficiency than prior systems, and might provide a foundation for developing a large-scale production system. Overall, plectasin shows potential as a novel, high-performance, and safe antibiotic for the treatment of refractory diseases caused by drug-resistant bacterial strains.

• 대한한방내과학회지
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• 제37권6호
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• pp.1042-1050
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• 2016

This case study reports on the effect of Korean medicine on a catheter-associated urinary tract infection (CAUTI) caused by multidrug-resistant Pseudomonas aeruginosa. An 83-year-old man diagnosed with stroke had dysuria, and it was found that an indwelling urinary catheter led to CAUTI. From laboratory tests, we identified multidrug-resistant Pseudomonas aeruginosa and applied Korean medicine to him. After herbal medication with acupuncture and moxibustion, we studied a urinalysis and urine culture again for follow-up. We found meaningful improvement in bacteriuria and bacterial identification. This case suggests that Korean medicine could have a beneficial effect on urinary tract infections caused by multidrug-resistant Pseudomonas aeruginosa.