• 디지털융복합연구
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• 제14권10호
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• pp.349-354
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• 2016

다양한 extended-spectrum ${\beta}$-lactamase (ESBL)를 생성하는 폐렴막대균의 출현 및 확산은 세균에 의한 감염증 치료에 어려움을 가중시키고 있다. 본 연구에서는 충청지역에서 분리된 폐렴막대균을 대상으로 ESBL 유전자를 검출하고 항균제 감수성 양상을 조사하였다. 또한 같은 클론에서 유래하였는지를 확인하기 위해 repetitive element sequence-based (REP)-PCR을 수행하였다. 충청지역에서 분리된 폐렴막대균 102균주 중 21균주가 CTX-M-14 및/또는 CTX-M-15를 생성하는 것으로 나타났으며 이 균주들은 3세대 cephalosporin 계열 항균제에 대해 70% 이상의 높은 내성율을 보였다. 본 연구에서 분리된 CTX-M형 ESBL생성 폐렴막대균은 다양한 클론으로부터 유래되었으며 그 중 일부는 지역사회에 확산되어 있음이 확인되었다. 이러한 폐렴막대균의 감염 및 확산을 방지하기 위해서는 감염관리의 강화가 필요하다. 아울러 좀 더 효과적인 내성세균의 관리를 위해서는 내성유전자의 생물학적 조사와 통계학적 분석을 통해 통합적으로 구축된 데이터베이스를 모니터링 할 필요가 있을 것으로 사료된다.

• 한국미생물·생명공학회지
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• 제17권4호
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• pp.321-326
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• 1989

m-Toluate 최소배지에서 선택적 enrichment culture를 통하여 82개의 세균의 균주를 분리하였으며, ol들 중 두 균주는 Pseudomonas cepacia, 한 균주는 P. Putida, 한 균주는 Yersinia intermedia, 그리고 한 균주는 Flavobacterium odoratum으로 동정되었다. P. cepacia SUB37은 P. putida mt-2의 TOL 플라스미드와 비슷한 크기의 플라스미드를 가지고 있었으며, Flavobacterium odoratum과 Yersinia intermedia는 이보다 더 큰 플라스미드를 갖고 있었다. P. cepacia SUB37은 streptomycin에 감수성을 나타내었으나, rifampicin에는 내성을 나타내었다. 플라스미드를 갖는 P. cepacia SUB37은 탄화수소를 해당 알콜과 알데히드를 거쳐서 benzoate와 toluate 로 분해하였다. 플라스미드 제거실험으로, P. Cepacia SUB37의 플라스미드에는 탄화수소 분해과정 중 toluene과 xylene을 benzoate, toluate로 분해하는 효소와, 계속하여 meta pathway를 거치는 단계의 효소를 코딩하는 유전자들이 있음이 확인되었다. 또한 P. cepacia SUB37은 생장이 왕성하였을 때 m-toluate를 거의 분해하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권2호
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• pp.323-336
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• 1996

This is a retrospective study on the patients with infection of the oral and maxillofacial region with the purpose of obtaining some useful data for diagnosis and treatment plan of that relatively common disease in dentistry. The used materials of study were 87 in total, including 52 male patients, 35 female patients who diagnosed and treated at the Department of the Dentistry in Hanyang Medical College Hospital for the period of Jan. 1990 to Dec. 1994. The author analyzed the distribution and incidence of sex, age, admission period, etiologic factors, etiologic teeth, treatment method of infections, pus culture, antibiotics sensibilities and medication. The result obtained as follows : 1. The developmental incidences by sex was superior in male by the ratio of 1.5 : 1 and the infection was most frequently occurred during the third decades(35.6%). 2. The number of admitted patients elevated in February, March, and April, and average of admission period was 9.8 days. 3. Main etiologic teeth showed on lower molar region in adult(63%) and upper molar region in primary dentition(46.1%). 4. Medications were administrated in all of the cases, and surgical incision and drainage were performed in 53% and extraction of the causative teeth were performed in 63.6% of all cases. 5. The most common involved fascial spaces were Buccal space(41.4%), Infraorbital space(27.6%), Submandibular space(16.1%),in order, and 9 cases(10.3%) were Ludwig's Angina. In 68.2% of the patients, and infection involved only one fascial space and in 21.8% of the patients, it involved to more fascial spaces. 6. The most causative organisms isolated from pus culture were Gram-positive facultative cocci(55.5%), and antibiotics sensitivities on the total isolated bacterial strains were exposed chloramphenicol(88.6%), Cephalothin(88.6%), Erythromycin(81.5%), Lincomycin(77.8%) in order, but it showed resistant on Gentamycin(58.3%), Tetracycline(56.5%), Methicillin(38.5%).

• 한국환경과학회지
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• 제6권2호
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• pp.173-182
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• 1997

The bacterial strains, which utilizes 2,4,4'-trichloro-2'-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highestt biodegradation activity was designated as EL-O47R The isolated strain EL-O47R was Identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH4)2SO4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the regradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-O47R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-O47R was moderately grown to Cd(NO3)2, ZnCl2, AgSO4, CuSO4 and HgCl2. This strain was sensitive to rifampicin and kanamycln but resistant to ampicillin, penicillin, tetracyclin and chloramphenlcol. Pseudomonas sp. EL-O47R was grown structurally related com- pounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.

• 한국축산식품학회지
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• 제38권5호
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• pp.851-865
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• 2018

This study investigated the prevalence of Listeria monocytogenes in slaughterhouses, and determined serovars and genotypes, and antibiotic resistance of the isolates obtained from slaughterhouses and humans in Korea. Two hundred ninety samples were collected from feces (n=136), carcasses [n=140 (cattle: n=61, swine: n=79)], and washing water (n=14) in nine slaughterhouses. Eleven human isolates were obtained from hospitals and the Korea Center for Disease Control and Prevention. Listeria monocytogenes was enriched and identified, using polymerase chain reaction (PCR) and 16S rRNA sequencing. Serovars and presence of virulence genes were determined, and genetic correlations among the isolates were evaluated by the restriction digest patterns of AscI. Antibiotic resistance of L. monocytogenes isolates were examined against 12 different antibiotics. Of 290 slaughterhouse samples, 15 (5.17%) carcass samples were L. monocytogenes positive. Most L. monocytogenes isolates possessed all the virulence genes, while polymorphisms in the actA gene were found between carcass and human isolates. Serovars 1/2a (33.3%) and 1/2b (46.7%) were the most frequent in carcass isolates. Genetic correlations among the isolates from carcass and clinical isolates were grouped within serotypes, but there were low geographical correlations. Most L. monocytogenes isolates were antibiotic resistant, and some strains showed resistance to more than four antibiotics. These results indicate that L. monocytogenes are isolated from carcass and human in Korea, and they showed high risk serotypes and antibiotic resistance. Therefore, intensive attentions are necessary to be aware for the risk of L. monocytogenes in Korea.

• 미생물학회지
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• 제22권1호
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• pp.41-48
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• 1984

아산 양어장에서 양식되고 있는 뱀장어 (Anguilla japonica)로부터 22주의 병원성 세균을 분리하여 그 생화학적 성질, 혈청학적 관계, 금붕어에 대한 감염성 및 여러 항생물질에 대한 감수성을 시험하였다. 22균주중 14주 (64%)는 Edwardsiella tarda 5주 (23%)는 Aeromonas hydrophila, 기타 3균주(14%)는 Vibrio anguillarum으로 동정되었다. 3가지 분리균중에서 E. tarda는 동일한 혈청형으로 그 분리율 및 금붕어에 대한 감염성이 가장 높았다. 이에 따라 E. tarda가 조사된 양어장의 뱀장어에서 발생하는 세균성 질병의 주 병원체로 판명되었다. 세 분리균주의 균액을 수조에 풀어 금붕어에 접촉시켰을 때 그 감염율은 세 균주 모두 상대적으로 낮았다. 10주의 분리균을 택해 12가지 항생물질에 대해 감수성 검사를 한 결과 하나에서 여섯가지 약제에 대해 저항성을 나타냈으며, 그 중 tetracycline 유도체와 sulfisoxazole에 대한 저항성이 현저하였다.

• 식물병연구
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• 제19권4호
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• pp.265-272
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• 2013

전국 7개도 14개 시 군의 주요 고추 재배지에서 시들음 증상을 나타내는 식물체의 땅가 줄기에서 분리 선별된 63개 풋마름병균들의 특성을 조사하였다. 고추에서 분리된 풋마름병균들은 고추(cv. 대왕)와 토마토(cv. 서광)에 강한 병원성을 나타냈다. 모든 병원균들은 배양적, 생리 생화학적 특성 및 특이 PCR 검출에 의하여 Ralstonia solanacearum으로 동정되었다. 고추에서 분리된 63개 풋마름병균들은 race 1 계통으로 2가지 biovar로 구분되었는데, biovar 3은 17개 균주로 27%였고 biovar 4는 46개의 균주로 73%였으며, biovar 4의 생리형이 우점계통이었다. Rep-PCR에 의한 국내 고추 풋마름병균들의 유전적 다양성을 확인한 결과, 70%의 유사성을 기준으로 12개의 group으로 구분되었다. 이러한 결과들은 국내 고추 풋마름병에 대한 방제와 저항성 품종 육성에 중요한 기초 자료를 제공할 것이다.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1841-1848
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• 2006

Insights into gene expression have the potential for improvement of antibiotic yield and the development of robust production hosts for use in recombinant biomolecule production. $Cubicin^{TM}$ (daptomycin for injection) is a recently approved antibiotic active against many Gram(+) pathogens, including those resistant to methicillin, vancomycin, and fluoroquinolones. Daptomycin is produced as a secondary metabolite by Streptomyces roseosporus. A 128 kb region of DNA including the daptomycin biosynthetic gene cluster (dpt) has been cloned. and sequenced. Using a selected array of nucleic acid probes representing this region, we compared the expression levels of the dpt genes between S. roseosporus wild-type (WT) and derived S. roseosporus high-producer of daptomycin (HP). We observed that the majority of the biosynthetic genes were upregulated in HP compared with WT; a total of 12 genes, including those encoding daptomycin synthetase, showed consistently and significantly higher expression levels, at least 5-fold, in HP compared with WT. In contrast, some genes, flanking the dpt cluster, were expressed at higher levels in the WT strain. The expression of housekeeping genes such as S. roseosporus rpsL, rpsG, and 16S (positive controls) and presumptive intergenic regions in the dpt cluster (negative control) were identical in the two strains. In addition, we compared transcription during the early, mid-log, and early-stationary phases of growth in the HP strain. The same set of genes was upregulated and downregulated under all conditions examined; housekeeping genes showed no relative change in expression level over the periods of growth tested. Analyses of this type would be of value in studies of strain improvement and also for the identification of gene regulation processes that are important for secondary metabolite production.

• Journal of Microbiology and Biotechnology
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• 제29권12호
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• pp.1916-1924
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• 2019

Outbreaks of staphylococcal food poisoning (SFP) causing serious human diseases and economic losses have been reported globally. Furthermore, the spread of Staphylococcus aureus with increased resistance to multiple antimicrobial agents has become a major concern in the food industries and medicine. Here, we isolated an endolysin LysSAP8, as one of the peptidoglycan hydrolases, derived from the bacteriophage SAP8 infecting S. aureus. This endolysin was tagged with a 6×His at the C-terminal of the target protein and purified using affinity chromatography. LysSAP8 demonstrated lytic activity against a broad spectrum of bacteria, which included a majority of the staphylococcal strains tested in this study as well as the methicillin-resistant S. aureus (MRSA); however, no such activity was observed against other gram-positive or gram-negative bacteria. Additionally, LysSAP8 could maintain bactericidal activity until 0.1 nM working concentration and after heat treatment at 37℃ for 30 min. The ability of LysSAP8 to lyse cells under varying conditions of temperature (4-43℃), pH (3-9), and NaCl concentrations (0-1,000 mM), and divalent metal ions (Ca²⁺, Co²⁺, Cu²⁺, Mg²⁺, Mn²⁺, Hg²⁺, and Zn²⁺) was examined. At the optimized condition, LysSAP8 could disrupt approximately 3.46 log CFU/ml of the planktonic cells in their exponential phase of growth within 30 min. In this study, we have suggested that LysSAP8 could be a potent alternative as a biocontrol agent that can be used to combat MRSA.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1992년도 학술강연회
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• pp.7-19
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• 1992

Fish pathology is one of the main scientific bases upon which this expansion in aquaculture has been dependent and requires a wide knowledge of the environmental constraints, the physiology and characteristics of the various pathogens, the responses of the host and the methods by which they may be controlled. The primary disease and parasite problems in aquaculture animals relate to viral, bacterial, fungal and protozoan epizootics. Parasitic nematodes, trematodes and cestodes are commonly found in aquaculture animals, but seldom are they present in concentrations sufficinet to cause significant problems. When an epizootic does occur and chemical treatment is indicated, the appropriate chemical must be selected and properly applied. We have antibiotics, sulfa, nitrofuran and other chemicals for treatment of fish diseases. Some may be mixed with the fred during formulation, added to the pellets of feed as a surface coating, given in the dorm of an injection or used as a bath. Even though a drug or chemical has been officially approved for use in aquaculture, the substance should never be used unless there is a clear need. Some of the reasions for this view are as follows: (1) the constant use of antibiotics can lead to the development of resistant strains of bacteria, (2) biofilter efficiency may be impaired or destroyed by chemicals added to closed recirculating water systems, and (3) the injudicious use of chemicals can have a damaging effect on the environment as well as on human.