• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.811-821
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• 2020

Mycobacterium tuberculosis produces mycolic acids which are relevant for persistence, recalcitrance to antibiotics and defiance to host immunity. c-di-GMP is a second messenger involved in transition from planktonic cells to biofilms, whose levels are controlled by diguanylate cyclases (DGC) and phosphodiesterases (PDE). The transcriptional regulator dosR, is involved in response to low oxygen, a condition likely happening to a subset of cells within biofilms. Here, we found that in M. bovis BCG, expression of both BCG1416c and BCG1419c genes, which code for a DGC and a PDE, respectively, decreased in both stationary phase and during biofilm production. The kasA, kasB, and fas genes, which are involved in mycolic acid biosynthesis, were induced in biofilm cultures, as was dosR, therefore suggesting an inverse correlation in their expression compared with that of genes involved in c-di-GMP metabolism. The relative abundance within trehalose dimycolate (TDM) of α-mycolates decreased during biofilm maturation, with methoxy mycolates increasing over time, and keto species remaining practically stable. Moreover, addition of synthetic c-di-GMP to mid-log phase BCG cultures reduced methoxy mycolates, increased keto species and practically did not affect α-mycolates, showing a differential effect of c-di-GMP on keto- and methoxy-mycolic acid metabolism.

• 생명과학회지
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• 제19권12호
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• pp.1847-1850
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• 2009

소 결핵은 만성적으로 서서히 진행 되어 쇠약해 지기 때문에 일반적으로 사후 검시 후에 확인 된다. 소결핵의 감염이 대부분 폐에서 발생하기 때문에 심한 경우에는 기침, 비루 및 호흡 곤란을 유발 한다. 본 고에서는 도축장에서 나온 사체의 심장, 간, 신장, 폐, 복수, 임파선 및 내장에서 얻은 시료를 분석한 것이다. 사체의 부검 검시도중 다양한 모양과 크기의 결핵 병변이 관찰 되었다. 백색 크림 색깔의 결핵은 화농성으로 임파선, 폐 및 장간막을 포함하여 흉막강에 퍼져 있었다. 폐와 임파선의 그램 염색과 Ziehl-Neelsen's acid-fast 염색 결과 강한 조직화학적 양성 반응을 나타내었다. Acid-fast에 염색된 유기체들이 현미경 검경에서 발견 되었다. 본 고에서는 의심원인체로 사료되는 Mycobacterium bovis의 조직학적 발견을 근거로 이에 의한 소결핵의 조직병리학적 소견을 보고하는 바이다.

• Tuberculosis and Respiratory Diseases
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• 제58권2호
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• pp.142-152
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• 2005

배 경 : 최근 결핵에 대한 새로운 백신 개발은 초회 면역 방법 및 추가 면역 방법을 이용하는 방향으로 연구되고 있다. 본 실험은 새로운 백신 후보 물질로서의 가능성을 알아보기 위하여 결핵균 adenylate kinase (AK), nucleoside diphosphate (NdK) 및 heat shock protein 70(Hsp70)의 결핵균에 대한 방어면역효능을 측정하였다. 방 법 : 재조합 단백질들을 정제하기 위하여 중합효소 연쇄반응으로 증폭한 결핵균 유전자 단편들을 E.coli expression vector, pQE30에 클로닝한 후, Ni-NTA resin을 이용하여 정제하였다. DDA와 재조합 단백질들을 마우스에 면역주사하고 면역반응 생성 유무를 확인하기 위하여 항체와 $IFN-{\gamma}$ 생성능을 측정하였다. 면역주사 한 마우스에 결핵균을 공기 감염시킨 후, 폐와 비장을 분리하여 결핵균 생균수 실험을 하였다. 결 과 : 재조합 단백질 AK, NdK 와 Hsp70을 면역보강제인 DDA를 이용하여 면역주사 한 결과에서, 생리식염수 혹은 DDA를 면역주사 한 마우스에 비교하여 재조합 단백질을 면역주사 한 마우스에서는 각 항원에 대해 항체와 $IFN-{\gamma}$ 생성능이 높게 나타났으나 결핵균에 대한 효과적인 방어면역효능은 나타나지 않았다. 결 론 : 마우스를 모델로 한 결핵균에 대한 방어면역효능 실험에서, 면역보강제 DDA를 이용한 재조합 단백질 AK, NdK 및 Hsp70을 면역주사 한 경우에는 결핵균의 성장을 효과적으로 조절하지 못하였다. 혼합 단백질 혹은 다른 T세포 면역보강제의 사용에 의한 추시가 필요하다.

• 한국동물위생학회지
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• 제41권2호
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• pp.71-78
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• 2018

Bovine tuberculosis (bTB) is a wide-spread zoonotic disease in cattle, which is casued by Mycobacterium bovis that is a part of Mycobacterium tuberculosis complex (MTC). This study describes a field trial conducted in 42 herds with the history of prevalence bovine tuberculosis. Two cell-mediated immunity tests, the gamma-interferon (${\gamma}-IFN$) assay and the single intradermal tuberculin test (SIT) were applied for the diagnosis of bovine tuberculosis in 5,289 animals. The ${\gamma}-IFN$ assay presented 144 (2.7%) head of cattle with the positive result, and 112 (2.1%) head of cattle were shown to be bTB-positive by the SIT. The positive concordance was 45.5%, and the negative concordance was 98.2%. The ${\gamma}-IFN$ assay showed more positive results in younger cattle, especially between 12 and 23 months of age. It is shown that the strategic combination of both cell-mediated immunity test methods is more efficient for the detection of bTB to reduce the number of false positive individuals which are being slaughtered.

• Journal of Yeungnam Medical Science
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• 제12권2호
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• pp.366-385
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• 1995

항산균 감염증의 예방 및 치료를 위하여는 역학적인 연구가 중요하다. 본 연구에서는 감염증의 분자역학적 연구를 위한 기법중 아직 항산균을 대상으로 pulsed-field gel electrophoresis (PFGE) 분석법을 확립하고자 하였다. PFGE분석에 적절한 제한효소는 DraI, AsnI 및 XbaI 등이었고 각 제한효소마다 최적의 PFGE조건은 서로 달랐다. DraI의 경우는 두단계로 나누어 전기영동을 시행하였다. 제1단계의 initial pulse는 10초 final pulse는 15초였으며 제2단계는 initial pulse는 60초 final pulse는 70초이었다. 전기영동시간은 각 단계마다 각각 14시간씩이었다. XbaI의 경우는 제2단계 없이 initial pulse가 3초 final pulse가 12초였고 전기영동시간은 22시간이었다. AsnI의 경우는 제2단계 없이 initial pulse가 5초 final pulse가 25초였고 전기영동시간은 22시간이었다. 모든 경우에 있어서 전압은 200V로 하였다. 표준균주로는 M. bovis BCG, M. tuberculosis 및 M. fortuitum등을 사용하였는데 PFGE분석상 동일균종내에서 표준균주들 간의 차이는 발견할 수 없었다. 임상에서 분리된 9주의 M. fortuitum 균주를 대상으로 AsnI 제한효소로 PFGE분석을 시행한 결과 2주만을 제외하고는 서로 간의 유전형 분류가 가능하였다. 균주간의 유전적 거리를 결정하기 위하여 cluster analysis를 시행한 결과 M. fortuitum 균주들은 크게 두 집단으로 나뉘었다. 제한효소 AsnI으로 동일 균종의 분류가 안되는 M. fortuitum 균주들은 XbaI 제한효소을 사용한 PFGE분석으로 유전형의 구분이 가능하였다. Cluster analysis를 시행한 결과 크게 두 집단으로 나뉘었던 M. fortuitum 균주들은 보다 복잡한 집단으로 분류되어 XbaI을 사용한 PFGE분석법이 M. fortuitum 균주분류를 위하여는 보다 적절함을 알 수 있었다. Cluster analysis에서 얻은 최대 % dissimilarity 값은 0.74(AsnI) 및 0.75(XbaI)로서 이 값은 arbitrarily primed polymerase chain reaction(AP-PCR)법보다는 높고 restriction fragment length polymorphism(RFLP) 법보다는 낮아 PFGE법이 RFLP를 보완하거나 대치할 수 있는 세균 유전형 분석법임을 알 수 있었다.

• 대한수의학회지
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• 제39권6호
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• pp.1119-1125
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• 1999

Since Robert Koch found tubercle bacilli in 1882, the studies on tubercle bacilli of human and animal had been carried out. Being old tuberculin(OT) introduced in 1890, the specificity of the diagnosis of tuberculosis has been improved by continual uses of heat concentrated synthetic medium(HCSM) and purified protein derivatives(PPD) tuberculin. Now, two types of tuberculin test are used worldwidly ; the single intradermal test(SIT) using bovine tuberculin and the single intradermal comparative tuberculin test(SICTT) using avian and bovine tuberculins. In the SICTT, each countries have used with different combination of both avian and bovine tuberculins' titers. However, this kinds of studies have not reported in Korea. Therefore, the studies on the combination of their tuberculins' titers were performed through intradermal test of guinea pigs sensitized with either Mycobacterium bovis or M avium and were examined in 10 cattles of SIT positive reactors. Also, IFN-${\gamma}$ assay, the latest diagnostic method of bovine tuberculosis, was experimentally applied to SIT positive reactors. For determining the optimal titers, sensitized guinea pigs with M bovis and M avium were intradermally injected avian and bovine tuberculin. In guinea pigs sensitized with M bovis, bovine tuberculin 50 T.U. showed significant difference from all tested concentrations of avian tuberculin(p < 0.05). In guinea pigs sensitized with M avium, there is significantly different between bovine tuberculin and avian tuberculin by 25 T.U.(p < 0.01). Therefore, optimal titers of bovine and avian PPD tuberculins' titers for the SICTT in Korea were 5,000 and 2,500 tuberculin units, respectively, and the swelling diffences between bovine and avian site in SIT positive reactors were above 3mm. Also, in IFN-${\gamma}$ assay, the 9 SIT positive reactors were showed all the positive reactions.

• 한국동물위생학회지
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• 제21권1호
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• pp.1-12
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• 1998

As the result of epidemiological analysis on bovine tuberculosis in Kyonggi province during the last ten years(1987-1996), 1. The annual incidence number of bovine tuberculosis positive farms in Kyonggi province fell down from 81 in 1987 to 14 in 1989. But the incidence is increased since 1990, in 1995 the incidence number was 102 farms of the most incidence. Total number of bovine tuberculosis positive farms were 456 farms(56.7%) in Kyonggi province during the 1987-1996 period. 2. The developmental trends of bovine tuberculosis positive heads was similiar to that of positive farms. Since 1993, the incidence was suddenly increased. Total number of bovine tuberculosis positive heads were 1,015 head(64.3%) in Kyonggi province during the 10 years. 3. Average incidence for rate during the last ten years(1987-1996) was 0.10%. The positive rate was suddenly increased since 1993 and in 1996, the positive rate was 0.23% of the highest incidence. 4. Regional Incidence number of bovine tuberculosis positive heads in Kyonggi province during the last seven years(1990-1996) was the most in Hwasung, Pochon, Pyungtek in order of Incidence and bovine tuberculosis positive density was 1.297% of the highest in Buchon. 5. In 244 farms(82.4%), bovine tuberculosis first occurred during the last seven years (1990-1996) but in farms over second occurrence, the number of bovine tuberculosis positive heads were 520 heads(58.2%).

• Genomics & Informatics
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• 제1권2호
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• pp.113-118
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• 2003

Among a number of antigens characterized in M leprae, an etiological agent of Leprosy, the 18 kDa antigen, is unique to M leprae. We have previously determined a sequence specific element in the 18 kDa gene of M leprae, which confers transcriptional repression. In this report, we have examined if the element could be applied to genes other than the 18 kDa gene of M leprae. To identify the roles of the regulatory sequence in heterologous promoter, we have constructed pB3 vector series, which contains BCG hsp65 promoter and the M leprae 18 kDa transcription repression responsive element in tandem using LacZ gene as a reporter gene. Cloning of hsp65 promoters of M bovis BCG or M smegmatis in front of LacZ gene resulted in normal $\beta$­galactosidase activity as expected. However, when the sequence element was placed between the promoter and the LacZ gene, $\beta$-galactosidase activity was reduced 10-fold less. Also we have examined with pB3(-) vector, that harbors the transcription repression responsive element in a reversed orientation, the $\beta$-galactosidase activity was found to be similar to pB3(+) vector. Thus, these results further confirm that M leprae 18 kDa transcription repression responsive element could regulate BCG hsp65 heterologous promoter and that the element could act as an operator for the transcription of mycobacteria.

• Journal of Dairy Science and Biotechnology
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• 제34권4호
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• pp.271-278
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• 2016

The main purpose of milk heat-treatment is to improve milk safety for consumer by destroying foodborne pathogens. Secondly, heat-treatment of milk is to increase maintaining milk quality by inactivating spoilage microorganisms and enzymes. Pasteurization is defined by the International Dairy Federation (IDF, 1986) as a process applied with the aim of avoiding public health hazards arising from pathogens associated with milk, by heat treatment which is consistent with minimal chemical, physical and organoleptic changes in the product. Milk pasteurization were adjusted to $63{\sim}65^{\circ}C$ for 30 minutes (Low temperature long time, LTLT) or $72{\sim}75^{\circ}C$ for 15 seconds (High temperature short time, HTST) to inactivate the pathogens such as Mycobacterium bovis, the organism responsible for tuberculosis. Ultra-high temperature processing (UHT) sterilizes food by heating it above $135^{\circ}C$ ($275^{\circ}F$) - the temperature required to destroy the all microorganisms and spores in milk - for few seconds. The first LTLT system (batch pasteurization) was introduced in Germany in 1895 and in the USA in 1907. Then, HTST continuous processes were developed between 1920 and 1927. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. At present, UHT is most commonly used in milk production.

• Tuberculosis and Respiratory Diseases
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• 제57권2호
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• pp.125-131
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• 2004

결핵균 감염에 대한 주요 방어 항원 물질로서 항원 85 복합체(Ag85A, B, C)가 주목되고 있다. 우리는 이들 항원들을 과발현하는 재조합 BCG를 클로닝하였고, 마우스 모델을 이용하여 결핵균 감염에 대한 재조합 BCG의 방어 효능을 알아보고자 하였다. 항원 85A를 과발현하는 재조합 BCG를 rBCG/FA, 항원 85B를 과발현하는 재조합 BCG를 rBCG/FB, 그리고, 이들 두 항원을 과발현하는 재조합 BCG를 rBCG/B.FA라고 명명하였고, 이들 항원들의 과발현 여부를 SDSPAGE상에서 확인한 결과, 재조합 BCG에서 항원 85A와 B 단백질이 BCG에 비해 과발현된 것을 알 수 있었다. 면역주사한 마우스에서 분리한 비장세포를 M. tuberculosis H37Rv의 culture filtrate protein(CFP)으로 자극하여 분비된 IFN-${\gamma}$ 농도를 측정한 결과에서는 rBCG/B.FA만이 BCG에 비해 높은 IFN-${\gamma}$ 농도를 나타내었으나, 마우스 모델을 이용한 결핵균 감염에 대한 재조합 BCG의 방어 효능 실험에서는 BCG와 뚜렷한 차이를 나타내지 못하였다.