• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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• pp.331-337
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• 1993

In order to understand the effect of duck hepatitis B virus (DHBV) on the economic performance of ducks, Three groups (DHBV congenitally infected, experimentally infected and DHBV negative) Brown Tsaiya ducks (Anas platyrhyncha) were used for experimental animals. Artificial insemination and pedigree hatching were applied in the propagation of ducklings, and the efficiency of vertical transmission and experimental infection was analyzed through the detection of DHBV DNA in the sera of 8-week-old offspring. The observation of the records of the first year indicated that the persistent infection had no significant effects on the performance of ducks, except the egg number of survival ducks up to 40 week of age. Thus DHBV infection did not appear to give ill effects to the economic performance of ducks in first laying year. A higher infection rate (85.3%) was obtained in congenital transmission than that (75.5%) of experimental infection. Both modes of infection did not reach 100% infectious rate, although some ducks developed transient viraemia in a tracing of DHBV DNA for 24 weeks to 11 challenged ducklings.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.84.1-84
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• 2003

Magnaporthe grisea, the casual agent of rice blast, forms an appressorium to penetrate its host. Much has been learned about environmental cues and signal transduction pathways, especially those involving CAMP and MAP kinases, on appressorium formation during the last decade. More recently, pharmacological data suggest that calcium/calmodulin-dependent signaling system is involved in its appressorium formation. To determine the role of phosphoinositide-specific phospholipase C (PI-PLC) on appressorium formation, a gene (WPLCl) encoding PI-PLC was cloned and characterized from M. grisea strain 70-15. Sequence analysis showed that MPLCl has alt five conserved domains present in other phospholipase C genes from several filamentous fungi and mammals. Null mutants (mplcl) generated by targeted gene disruption exhibited pleiotropic effects on conidial morphology, appressorium formation, fertility and pathogenicity. mplcl mutants developed nonfunctional appressoria and are also defective in infectious growth in host tissues. Defects in appressorium formation and pathogenicity in mplcl mutants were complemented by a mouse PLCdelta-1 cDNA under the control of the MPLCl promoter. These results suggest that cellular signaling mediated by MPLCl plays crucial and diverse roles in development and pathogenicity of M. grisea, and functional conservation between fungal and mammalian Pl-PLCs.

• 생명과학회지
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• 제19권2호
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• pp.284-288
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• 2009

선천성 면역은 숙주의 물리적 방어벽을 뚫고 침입하는 감염성 질병 원인균에 대항하는 첫 번째 방어로서 아주 중요한 역할을 한다. Mannose-binding lectin (MBL 또는 mannan-binding protein, MBP)은 혈청 내에 존재하는 면역성 단백질로서 감염 후 즉시 유발되는 acute phase response의 특정 단백질이다. MBL 단백질은 세균, 바이러스, 곰팡이, 기생충 등의 탄수화합물 구조에 결합하여 식균 작용을 돕거나 보체경로를 활성화 시킨다. MBL 단백질은 C-말단이 탄수화물을 인식하는 도메인이며, 연결 목 부위와 콜라겐 부위로 구성되어 있다. 혈청 내의 MBL 농도가 낮으면 높은 빈도로 면역결핍현상이 관찰된다고 알려져 있다. MBL 단백질의 기능과 유전에 대해 많은 연구가 되어져 왔으나 아직 MBL 단백질 복합체 등에 대한 연구는 많이 이루어져 있지 않다. 따라서 MBL 연구에 필수적인 MBL cDNA 제조와 재조합 단백질의 합성, 그리고 재조합 단백질을 항원으로 사용하여 polyclonal antibody를 생산한 연구 결과를 보고하는 바이다. 본 연구결과로 획득한 MBL cDNA, 재조합 단백질과 anti-MBL 항체는 앞으로의 MBL 연구에 절대적으로 필요한 도구가 될 것으로 생각된다.

• 미생물학회지
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• 제34권1_2호
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• pp.64-68
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• 1998

한국에서 분리된 전염성 조혈괴저바이러스(infectious hematopoietic necrosis virus, IHNV)인 IHNV-PRT의 특성을 규명하기 위하여 IHNV-PRT의 matrix 단백질인 M1 및 M2를 암호화하고 있는 cDNA를 클로닝하여 이들의 염기서열을 분석하였다. M1은 693 bp 크기의 open reading frame을 포함하였으며 이로부터 230개의 아미노산으로 구성된 25.9 kDa의 분자량을 가진 단백질이 합성될 수 있다. M2는 588 bp 크기의 open reading frame을 지니고 있으며 195개의 아미노산으로 구성된 21.9 kDa의 분자량을 지닌 단백질이 합성될 수 있다. IHNV-PRT의 M1과 M2의 아미노산 서열을 외국에서 분리된 IHNV들과 비교 분석한 결과 M1은 92-93%, M2는 97%의 상동성을 보였다. 이러한 사실은 IHNV의 M 단백질 유전자들은 IHNV의 strain에 관계없이 매우 보존되어 있음을 나타내준다.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.862-868
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• 2014

Certain Escherichia coli (E. coli) strains have the ability to cause diarrheal disease. Five types of diarrheagenic E. coli have been identified, including EHEC, ETEC, EPEC, EAEC, and EIEC. To detect these five diarrheagenic types rapidly, we developed a one-step multiplex PCR (MP-PCR) assay using nine primer pairs to amplify nine virulence genes specific to the different virotypes, with each group being represented (i.e., stx1 and stx2 for EHEC, lt, sth, and stp for ETEC, eaeA and bfpA for EPEC, aggR for EAEC, and ipaH for EIEC). The PCR primers were constructed using MultAlin. The sensitivity and specificity of the constructed multiplex PCR primers were measured using DNA isolated from diarrheagenic E. coli strains representing each group. The limits of detection were as follows: $5{\times}10^1CFU/ml$ for EHEC, $5{\times}10^3CFU/ml$ for ETEC expressing lt and sth, $5{\times}10^4CFU/ml$ for ETEC expressing stp, $5{\times}10^2CFU/ml$ for EPEC, $5{\times}10^4CFU/ml$ for EAEC, and $5{\times}10^2CFU/ml$ for EIEC. To confirm the specificity, C. jejuni, C. perfringens, S. Typhimurium, V. parahaemolyticus, L. monocytogenes, Y. enterocolitica, B. cereus, and S. aureus were used as negative controls, and no amplification was obtained for these. Moreover, this kit was validated using 100 fecal samples from patients with diarrhea and 150 diarrheagenic E. coli strains isolated in Korea. In conclusion, the multiplex PCR assay developed in this study is very useful for the rapid and specific detection of five diarrheagenic E. coli types. This single-step assay will be useful as a rapid and economical method, as it reduces the cost and time required for the identification of diarrheagenic E. coli.

• The Plant Pathology Journal
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• 제31권4호
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• pp.433-437
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• 2015

The infectious full-length cDNA clones of Cucumber green mottle mosaic virus (CGMMV) isolates KW and KOM, which were isolated from watermelon and oriental melon, respectively, were constructed under the control of the cauliflower mosaic virus 35S promoter. We successfully inoculated Nicotiana benthamiana with the cloned CGMMV isolates KW and KOM by Agrobacterium-mediated infiltration. Virulence and symptomatic characteristics of the cloned CGMMV isolates KW and KOM were tested on several indicator plants. No obvious differences between two cloned isolates in disease development were observed on the tested indicator plants. We also determined full genome sequences of the cloned CGMMV isolates KW and KOM. Sequence comparison revealed that only four amino acids (at positions 228, 699, 1212, and 1238 of the replicase protein region) differ between the cloned isolates KW and KOM. A previous study reported that the isolate KOM could not infect Chenopodium amaranticolor, but the cloned KOM induced chlorotic spots on the inoculated leaves. When compared with the previously reported sequence of the original KOM isolate, the cloned KOM contained one amino acid mutation (Ala to Thr) at position 228 of the replicase protein, suggesting that this mutation might be responsible for induction of chlorotic spots on the inoculated leaves of C. amaranticolor.

• The Plant Pathology Journal
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• 제35권5호
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• pp.538-542
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• 2019

In 2017, two new tomato mosaic virus (ToMV) isolates were collected from greenhouses in Buyeo, Chungcheongnam-do, South Korea. Full-length cDNAs of the new ToMV isolates were cloned into dual cauliflower mosaic virus 35S and T7 promoter-driven vectors, sequenced and their pathogenicities investigated. The nucleotide sequences of isolates GW1 (MH507165) and GW2 (MH507166) were 99% identical, resulting in only two amino acid differences in nonconserved region II and the helicase domain, Ile668Thr and Val834Ile. The two isolates were most closely related to a ToMV isolate from Taiwan (KJ207374). Isolate GW1 (Ile668, Val834) induced a systemic hypersensitive response in Nicotiana benthamiana compared with the isolate GW2, which a single residue substitution showed was due to Val834.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.244.2-245
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• 2000

No Abstract, See Full Text

• 대한수의학회지
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• 제61권2호
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• pp.11.1-11.5
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• 2021

To evaluate avian hepatitis E virus (aHEV) as an RNA vaccine platform, ORF2 of aHEV was replaced by heterologous genes, such as eGFP and HA-tag, in aHEV infectious cDNA clones. eGFP and HA-tag replicons were expressed in LMH cells. To confirm expression of the heterologous protein, ORF2 was replaced with the antigenic S1 gene of IBV. The IBVS1 replicon was expressed in LMH cells. To our knowledge, this is the first investigation showing the potential as a RNA vaccine platform using an aHEV. In the future, it may be used in the development of RNA vaccines against various pathogens.

• 한국미생물·생명공학회지
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• 제31권4호
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• pp.377-382
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• 2003

1차 DEAE-Toyopearl 650 M ion exchange column chromatography 및 2차DEAE-Sephadex A-50 ion exchange column chromatography에 의해 정제를 수행한 결과 15.92 units/mg의 정제배율 및 비활성은 92배, 정제 효소의 순도는 SDS-PAGE에 의해 단일 밴드를 나타내었으며, 분자량은 43kDa으로 추정되었다. 래트의 대장암 세포인 RR1022세포와, 사람의 난소암 세포인 SKOV-3 세포에서 RPMI1640 배지와 methionine이 결핍된 RPMI1640 배지를 처리한 결과 정상군에 비해 대조군의 $^{11}$ C-methionine의 섭취 변화가 증가하였다. 종양세포인 RR1022, SKOV-3세포에 methioninase 투여하여 종양세포의 생존율의 변화를 trypan blue 기법으로 확인한 결과 배지내에서 종양세포의 증식에 필요한 methionine의 농도가 감소하여 DNA, RNA, Protein의 합성을 저해한다고 사료된다. 종양세포인 RR1022, SKOV-3세포에 methioninase를 투여한 결과 정상군에 비해 대조군이 시간 지나면서 $^{11}$ C-methionine의 섭취 변화가 증가하였다. 동물의 $^{11}$ C-methionine PET 영상 결과 종양과 염증병변이 모두 관찰되었다. rMET를 투석한 결과 염증병변의 섭취에 비하여 종양의 섭취가 증가하는 경향이 관찰되었으며, 정제한 methioninase를 투여하고 영상을 얻은 경우에도 종양 섭취가 염증보다 높게 나타났다. 종양세포에 methioninase를 처리하면 methionine의 섭취 요구량은 시간이 지나면서 증가하였으며 생존율은 감소하였다. 종양 동물모델에서도 methioninase를 투여한 경우 종양의 좋은 $^{11}$ C-methionine 섭취를 관찰할수 있었으며 methioninase의 이용이 종양의 검출에 유용하게 이용될 수 있을 것으로 사료되었다.