• BMB Reports
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• 제37권3호
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• pp.304-313
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• 2004

Three-dimensional (3D) models for the 65-kDa activated Cry4A and Cry4B $\delta$-endotoxins from Bacillus thuringiensis subsp. israelensis that are specifically toxic to mosquito-larvae were constructed by homology modeling, based on atomic coordinates of the Cry1Aa and Cry3Aa crystal structures. They were structurally similar to the known structures, both derived 3D models displayed a three-domain organization: the N-terminal domain (I) is a seven-helix bundle, while the middle and C-terminal domains are primarily comprise of anti-parallel $\beta$-sheets. Circular dichroism spectroscopy confirmed the secondary structural contents of the two homology-based Cry4 structures. A structural analysis of both Cry4 models revealed the following: (a) Residues Arg-235 and Arg-203 are located in the interhelical 5/6 loop within the domain I of Cry4A and Cry4B, respectively. Both are solvent exposed. This suggests that they are susceptible to tryptic cleavage. (b) The unique disulphide bond, together with a proline-rich region within the long loop connecting ${\alpha}4$ and ${\alpha}5$ of Cry4A, were identified. This implies their functional significance for membrane insertion. (c) Significant structural differences between both models were found within domain II that may reflect their different activity spectra. Structural insights from this molecular modeling study would therefore increase our understanding of the mechanic aspects of these two closely related mosquito-larvicidal proteins.

• Parasites, Hosts and Diseases
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• 제48권1호
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• pp.35-41
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• 2010

We investigated the seasonality of Anopheles mosquitoes, including its species composition, density, parity, and population densities of mosquitoes infected with the parasite in Ganghwa-do (Island), a vivax malaria endemic area in the Republic of Korea. Mosquitoes were collected periodically with a dry-ice-tent trap and a blacklight trap during the mosquito season (April-October) in 2008. Anopheles sinensis (94.9%) was the most abundant species collected, followed by Anopheles belenrae (3.8%), Anopheles pullus (1.2%), and Anopheles lesteri (0.1%). Hibernating Anopheles mosquitoes were also collected from December 2007 to March 2008. An. pullus (72.1%) was the most frequently collected, followed by An. sinensis (18.4%) and An. belenrae (9.5%). The composition of Anopheles species differed between the mosquito season and hibernation seasons. The parous rate fluctuated from 0% to 92.9%, and the highest rate was recorded on 10 September 2008. Sporozoite infections were detected by PCR in the head and thorax of female Anopheles mosquitoes. The annual sporozoite rate of mosquitoes was 0.11% (2 of 1,845 mosquitoes). The 2 mosquitoes that tested positive for sporozoites were An. sinensis. Malarial infections in anopheline mosquitoes from a population pool were also tried irrespective of the mosquito species. Nine of 2,331 pools of Anopheles mosquitoes were positive. From our study, it can be concluded that An. sinensis, which was the predominant vector species and confirmed as sporozoite-infected, plays an important role in malaria transmission in Ganghwa-do.

• 한국응용곤충학회지
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• 제49권2호
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• pp.151-158
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• 2010

토양에서 분리한 구형의 내독소단백질을 가지는 18개의 균주 중, 이집트숲모기와 지하집모기에 90%이상의 살충활성을 보이는 Bacillus thuringiensis subsp. israelensis CAB199 균주를 선발하였다. 이 균주는 습지에 발생한 이나도미집모기에도 높은 살충효과를 나타내었다. 모기유충의 행동패턴은 주로 호흡을 위해 수면에서 주로 활동하고 있어, Bti 균주를 유효성분으로 하는 제제가 수면 위에 장시간 부유 할 수 있는 제형을 선발하고자 하였다. 수화제와 액상수화제의 두 가지 형태의 제형을 만들어 실내에서의 살충효과 및 습지에서의 방제효과를 확인한 결과, 실내에서의 경우에는 액상수화제 제형이 실험한 3종의 모기유충에 대해 속효적이며 높은 살충율을 보여주었고, 습지에서도 이나도미집모기에 대하여 가장 좋은 활성을 나타내었다.

• 한국응용곤충학회지
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• 제59권1호
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• pp.41-54
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• 2020

안동지역 농가 주변의 정수에서 두 종의 모기가 채집되었다. 형태적 특징을 바탕으로 이들이 한국숲모기(Aedes koreicus)와 줄다리집모기(Culex vagans)로 각각 동정되었다. 또한, DNA 바코드 서열을 분석한 결과 이러한 동정 결과를 뒷받침하였다. 이들 모기류 유충에 대해 곤충병원세균인 Bacillus thuringiensis subsp. israelensis (BtI)가 살충효과를 보였으며 유사한 B. thuringiensis subsp. kurstaki에 비해 우수하였다. 한편 곤충의 면역억제를 유발하여 B. thuringiensis의 병원력을 높인다고 알려진 Xenorhabdus 세균류의 배양액을 BtI에 첨가하여 이들 모기류에 대한 살충력 증가 효과 유무를 확인하였다. 분석에 이용된 3 종류의 Xenorhabdus 세균배양액 가운데 X. ehlersii (Xe)의 배양액이 비교적 다른 세균배양액에 비해 두 종의 모기류에 대해서 BtI의 살충력을 높이는 것으로 나타났다. 이를 바탕으로 Xe 세균배양액으로부터 유기용매 추출물의 생물활성을 분석한 결과 모기의 혈구 활착행동을 뚜렷이 억제시키는 면역억제자가 존재한다는 것을 확인하였다. 본 연구는 BtI와 Xe의 두 세균을 혼합한 비티플러스 미생물제제가 한국숲모기와 줄다리집모기의 방제에 효과적이라는 것을 제시한다.

• Parasites, Hosts and Diseases
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• 제40권1호
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• pp.45-54
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• 2002

Field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18-27 September 2000 in a malarious area near Paekyeon-ri (Tongil-Chon) and Camp Greaves in Paju County, Kyonggi Province, Republic of Korea. The host-seeking activity for common mosquito species, including the primary vector of Japanese encephalitis, Culex tritaeniorhynchus Giles. was determined using hourly aspirator collections from a human and propane lantern-baited Shannon trap doting hours when temperatures exceeded $15^{\circ}C$. The total number of mosquitoes and number of each species captured during the test was compared using a block design. Significant differences were observed for the total number of mosquitoes collected, such that, the Mosquito MagnetTM with octenol > Shannon trap > ABC light trap with light and dry ice > Miniature Black Light trap (manufactured by John W. Hock) $\geq$ New Jersey Trap > ABC light trap with light only. Significant differences in numbers collected among trapes were noted for several species including: Aedes vexans (Meigen), Anopheles lesteri Baisas and Hu. An. sinensis Weidemann, An. sineroides Yamada, An. yatsushiroensis Miyazaki. Culex pipiens pallets Coquillett L., Cx. orientalis Edwards and Cx. tritaeniorhynchus. Host-seeking activity for most common species showed a similar bimodal pattern. Results from these field trap evaluations can significantly enhance current vector and disease surveillance efforts especially for the primary vector of Japanese encephalitis, Cx. tritaeniorhunchus.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2004년도 춘계 학술발표회
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• pp.106-106
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• 2004

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2001년도 추계 합동 심포지엄 및 학술발표대회
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• pp.149-149
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• 2001

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 공동 춘계학술대회
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• pp.77.1-77
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• 1999

No Abstract, See Full Text

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 추계 합동 특강 및 학술발표대회
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• pp.26-27
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• 2002

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 추계 합동 특강 및 학술발표대회
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• pp.152-152
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• 2002