• 대한수의학회지
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• 제42권2호
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• pp.201-208
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• 2002

Staphylokinase is seldom formed by animal Staphylococcus aureus strains. In this study, 76(72.4%) of 105 Staph aureus strains isolated from bovine mastitis were found to produce a staphylokinase. These staphylokinase producing strains were tested for lysogenic conversion by means of delysogenization procedure and isolation of serotype B and F converting phages. By the application of delysogenization method comprised of UV irradiation and acriflavine treatment to 76 staphylokinase-positive strains, the delysogenized cells could be observed in 29(38.2%) of the strains and delysogenization rates in 16(55.2%) of 29 delysogenized strains were 0.9% or less. A total of 7 serological group F phages were isolated from 76 staphylokinase-positive strains, and these phages could be again divided into three groups by the immunity reaction. Of 7 serotype F phages, 2 were isolated from the original lysogenic strains producing colonies of delysogenized cells after delysogenizing treatments and 5 were isolated from strains in which delysogenized cells were not observed after delysogenizing treatments. Difference of sensitivities to serological group F phages between original lysogenic strains and strains from which delysogenized cells were not isolated after delysogenizing treatments was not observed These data suggest that staphylokinase production of the remaining 42 strains might be also mediated by lysogenic conversion.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2064-2070
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• 2018

Pseudomonas tolaasii 6264 is a representative strain that causes bacterial blotch disease on the cultivated oyster mushroom, Pleurotus ostreatus. Bacteriophages are able to sterilize the pathogenic P. tolaasii strains, and therefore, they can be applied in creating disease-free mushroom cultivation farms, through a method known as "phage therapy". For successful phage therapy, the characterization of phage-resistant strains is necessary, since they are frequently induced from the original pathogenic bacteria in the presence of phages. When 10 different phages were incubated with P. tolaasii 6264, their corresponding phage-resistant strains were obtained. In this study, changes in pathogenic, genetic, and biochemical characteristics as well as the acquired phage resistance of these strains were investigated. In the phylogenetic analyses, all phage-resistant strains were identical to the original parent strain based on the sequence comparison of 16S rRNA genes. When various phage-resistant strains were examined by three different methods, pitting test, white line test, and hemolytic activity, they were divided into three groups: strains showing all positive results in three tests, two positive in the first two tests, and all negative. Nevertheless, all phage-resistant strains showed that their pathogenic activities were reduced or completely lost.

• Mycobiology
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• 제34권4호
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• pp.196-199
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• 2006

Effects of various preservation periods and subcultures on fruiting body formation of Cordyceps militaris were investigated using EFCC C-10995 single ascospore strains. Fruiting body formation by original strains was profuse when preserved at $4^{\circ}C$ for $5{\sim}6$ months. Fruiting from subcultures was stable till second to sixth subcultures, after which it decreased sharply. The more the colony color of subcultures changed, the less the fruiting bodies formed. Liquid inoculum preparation of single ascospore strains in the same or separate broths did not affect fruiting body formation. Similarly, two strains C-10995-3 and C-10995-6 in different numbers during liquid inoculum preparation produced similar fruiting bodies.

• 약학회지
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• 제2권1_2호
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• pp.41-47
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• 1953

"Kimchi" is a most popular pickled Vegetables in Korea. In this paper, eight strains of gram positive rocls and two strains of gram positive cocci are isolated from "Kimchi". For the each isolated strains, the acid production test against carbohydrate and production test of amylase, protease, esterase, and general biological tests are investigated. The most active one for the amylase production is No.2 strain the most active one for the Protease production is No.5,6, and 9 strains. And that for Esterase production is No.9 strain (see the original paper on the results in this journal page)

• 한국균학회소식:학술대회논문집
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• 한국균학회 2009년도 추계학술대회 및 정기총회
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• pp.14-16
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• 2009

Poria cocos is an importantant medical macrofungus,the sclerotium of Poria cocos has specific value as the drug material. There are few papers about its breeding and spawn rejuvenation. In this project, the protoplasts of cultivated strain T and wild strain L were prepared and treated separately by ultraviolet and heating, then fused with the PEG6000. The tural fusants were selected and identified by the affinity and ISSR analysis. 71 incompatibility strains between parents and reg regenerations were obtained from 118 regenerations by the affinity analysis. Five incompatibility strains were amplified with different primers, the results were showed that they had specific bands of both parents in the profile amplified with 3 primers, which proved these 5 strains were fusants by means of molecular biology marker. On the other hand, 25 strain were selected from 168 protoplast regenerations of cultivated strain T for cultivation experiment. The fresh sclerotium weight of these protoplast regenerations were better than the original strain.significantil 3 strains (T-1, T-4, T-7) increased respectively 118%, 73% and 73% than original strain. This method could be the effective in the rejuvenation Poria cocos.

• 한국균학회지
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• 제9권2호
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• pp.93-97
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• 1981

본(本) 시험(試驗)은 양송이 마이코곤 병원균(病原菌) 중(中) 최근(最近)에 출현(出現)되어 703호(號) 계통(系統)에도 피해(被害)를 입히는 변이(變異) 균주(菌株)의 특성(特性)을 기존(旣存) 균주(菌株)와 비교(比較) 시험(試驗)한 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 본(本 )병원균(病原菌)의 변이(變異) 균주(菌株)는 PSA에서 배양시(培養時) $25^{\circ}C$에서 생육(生育)이 가장 양호(良好)하였고 $10^{\circ}C$와 $35^{\circ}C$에서는 극(極)히 저조(低調)하였으며 기존(旣存) 균주(菌株)도 거의 동일(同一)한 결과(結果)였다. 2. 본(本) 병원균(病原菌)의 기존(旣存) 균주(菌株)는 pH 6.0에서 旣凉 株는 pH 6.0에서, 변이(變異) 균주(菌株)는7.0정도(程度)에서 생육(生育)이 양호(良好)하였다. 3. 본(本) 병원균(病原菌)의 사멸(死滅)은 $50^{\circ}C$에서 기존(旣存) 균주(菌株)가 40분(分), 변이(變異) 균주(菌株)가 60분(分) 열처리(熱處理)로서 완전(完全)히 이루어졌다. 4. 본(本) 병원균(病原菌)의 후막포자(厚膜胞子)는 PSA에서 6일후(日後)에, 변이(變異) 균주(菌株)는 4일후(日後)부터 다량(多量) 형성(形成)되었다. 5. 방제(防除) 약제(藥劑)로서 기존(旣存) 균주(菌株)에 대해서는 Benlate나 Homai만 약효(藥效)가 높게 나타나나, 변이(變異) 균주(菌株)에 대해서는 Delan이나 Dithane Z-78도 약효(藥效)가 높게 나타났다. 6. 양송이 공시(供試) 계통중(系統中) 마이코곤 이병률(罹病率)이 40% 이하(以下)인 것은 기존(旣存) 균주(菌株)에 대(對)하여 22계통(系統), 변이(變異) 균주(菌株)에 대(對)하여 12계통(系統)이 있었다. 7. 양송이 계통중(系統中) 저항성(抵抗性) 이 강(强)한 것은 크림색(色)이나 갈색 계통(系統)이 많으며 백색계통(白色系統)은 대체적으로 약(弱)하며 그중 린피(鱗皮)가 있는 것은 약간 강(强)한 경향(傾向)을 보였다.

• 한국동물위생학회지
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• 제35권3호
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• pp.169-174
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• 2012

Japanese encephalitis virus (JEV) is one of the main causes of viral encephalitis in human and animals. For over 30 years, a live attenuated JEV vaccine strain has been used in the veterinary field, and it is required to conduct quality evaluation studies on the commercial vaccines. For the quality control of live attenuated JEV vaccine, we investigated the nucleotide sequence similarity of prME gene derived from five JEV vaccines commercially available in pigs in Korea. The Vero cells infected with JEV vaccines showed specific cytopathic effect, which was characterized by rounding and detached cells. In the phylogenetic analysis, all of the vaccine strains showed a close relationship with the original vaccine seed strain (Anyang 300) and clustered into the genotype 3. In comparison of the nucleotide and deduced amino acid sequences of prME genes with the original strain, all JEV vaccine strains showed high amino acid similarity ranging from 98.9% to 99.5%, but had several point mutations, probably due to high mutation rates of viral RNA polymerase by several virus passages. Even though the current JEV vaccine strains have been maintained and produced for a long period of time, the genetic characterization of them have been rarely changed. However, since the mid 1990's, molecular epidemiology of JEV has been changed sharply from genotype 3 to genotype 1 in Korea, further studies on new vaccine strains to genotype 1 is required for more effective prevention in the field.

• 한국동물학회지
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• 제14권3호
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• pp.125-131
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• 1971

초파리의 번데기 시기에 NaCl을 처리하였을때 우활율과 SD작용에 변동이 있는가를 보기 위하여 6가지 계통, 즉 SD 계통 4가지와 다른계통 2가지를 써서 6가지 농도의 NaCl사육배지를 만들어 실험한 결과는 다음과 같다. 1. 우화율(즉 NaCl에 대한 저항성)은 계통간이나 NaCl의 농도간이나 다같이 매우 유의적인 차이를 보이고 있다. 2. 우화율은 NaCl 농도가 높을수록 낮아지는 경향이 있으며, 이 저하는 완만한 편이고 발생의 각 단계중에서 번데기 시기가 NaCl의 영향을 가장 적게 받는다. 3. SD계통의 우화율은 다른 계통에 비하여 대체로 낮은 편인데, 이것은 SD계통이 NaCl에 대한 저항성이 다른 계통에 비하여 약한 것을 말한다. 4. SD작용의 척도라고 볼 수 있는 k 값은 NaCl의 농도간에 유의한 차가 없으나 계통간에는 유의적인 차이를 보이고 있으며, Original-SD 계통의 k값은 Recombinant-SD계통의 k값보다 높고 또한 안정성을 나타내고 있다. 5. NaCl은 SD작용에 영향을 미치지 못하며 발생의 어느 단계에 NaCl을 처리하거나 관계없이 일단 우화만 되면 SD작용에는 변동이 없다.

• 대한수의학회지
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• 제49권3호
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• pp.243-248
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• 2009

After the original identification of canine parvovirus (CPV) type 2 (CPV-2) in 1978, new antigenic variants such as CPV-2a, CPV-2b and CPV-2c have become widespread in the most countries. In this study, the genetic analysis of canine parvovirus was investigated in a total of 13 CPV vaccines, which have been licensed in Korea since late 1980s, and a field isolate of CPV from a dog with CPV infection clinical symptom. The partial VP2 gene of CPV was amplified and sequenced from 13 vaccine strains and one field isolate. The results showed that of the 13 vaccine strains, 10 strains belong to the CPV-2, 2 strains to CPV-2b, the remaining and one isolate to CPV-2a type, respectively. Several mutations of amino acids were detected at residues of the critical region of the commercial vaccine strains. These data suggest that new type of vaccines containing CPV-2a or CPV-2b/2c type may be required for the better prevention of new CPV infection in dog population in Korea, because CPV-2 contained in most licensed vaccines has been replaced by antigenic variants designated CPV-2a or CPV-2b/c in the worldwide dog population.

• 미생물학회지
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• 제28권3호
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• pp.236-242
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• 1990

여러가지 난분해성 방향족 화합물을 분해하는 균주들을 개발하기 위해 2,4-D 분해 유전자를 갖는 재조합 플라스미드 pKG2. 나프탈렌 분해 유전자를 갖는 재조합 플라스미드 pKG3 그리고 TOL 플라스미드를 합성세제 분해능을 갖는 P p pulida KUD12와 프탈산에스테르를 분해하는 P.pUlida KUPlO에 각각 형질전환 또는 접합시켰다. P.pulida KUD12로부터 KUDIOl(pKG2), KUDI02(pKG3). KUDI03(TOL), KUD202(pKG3, TOL) 균주판, 또 P.pulida KUPlO으로부터 KUD 106(pKG2). KUD107(pKG3), KUD108(TOL) 균주을 각각 개발하였다. 개발균주의 분해능은 KUD101과 KUD102 그리고 KUD107이 원분해 균주와 비솟하였고, KUDI03과 KUD106 그리고 K KUD202는 원분해 균주보다 분해능이 떨어졌고 KUD108의 분해능은 원균주보다 우수하였다. 개발균주들의 혼합배양 에서는 KUD 107과 KUD108의 혼합배양이 다른 혼합배양틀보다 분해능이 우수한 것으로 나타났다.