• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.865-871
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• 2002

A bacterium having strong chitinolytic activity on $0.2\%$ colloidal chitin-containing agar medium was isolated from coastal soil in Korea. Based on the nucleotide sequence of conserved segment of a 165 rRNA gene, the bacterium was identified as Paenibacillus illinoisensis KJA-424. The population of P. illinoisensis KJA-424 and chitinase activity significantly increased for the first 2 days of incubation. On SDS-PACE analysis with $0.01\%$ glycol chitin, three protein bands (63, 54, and 38 kDa) with chitinolytic activity were detected tooted. The effect of P illinoisensis KJA-424 on the egg hatch of root-knot nematode (Meloidogyne incognita) was investigated. After 7 days of incubation with the chitinase-producing P. illinoisensis KJA-424, none of the eggs hatched, whereas a $39.8\%$ egg hatching rate was observed in the water control. Inverted and scanning electron microscopic observations demonstrated that P. illinoisensis KJA-424 deformed and destroyed the eggshell of M. incognita. In conclusion, chitinase-produced by p. illinoisensis KJA-424 caused the lysis of M. incognita eggshell and resulted in the inhibition of egg hatching in vitro.

• Plant Biotechnology Reports
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• 제3권2호
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• pp.147-155
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• 2009

Oryza grandiglumis Chitinase IVa (OgChitIVa) cDNA encoding a class IV chitinase was cloned from wild rice (Oryza grandiglumis). OgChitIVa cDNA contains an open reading frame of 867 nucleotides encoding 288 amino acid residues with a predicted molecular weight of 30.4 kDa and isoelectric point of 8.48. Deduced amino acid sequences of OgChitIVa include the signal peptide and chitin-binding domain in the N-terminal domain and conserved catalytic domain. OgChitIVa showed significant similarity at the amino acid level with related monocotyledonous rice and maize chitinase, but low similarity with dicotyledoneous chitinase. Southern blot analysis showed that OgChitIVa genes are present as two copies in the wild rice genome. It was shown that RNA expression of OgChitIVa was induced by defense/stress signaling chemicals, such as jasmonic acid, salicylic acid, and ethephon or cantharidin and endothall or wounding, and yeast extract. It was demonstrated that overexpression of OgChitIVa in Arabidopsis resulted in mild resistance against the fungal pathogen, Botrytis cinerea, by lowering disease rate and necrosis size. RT-PCR analysis showed that PR-1 and PR-2 RNA expression was induced in the transgenic lines. Here, we suggest that a novel OgChitIVa gene may play a role in signal transduction process in defense response against B. cinerea in plants.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2002년도 추계 합동 특강 및 학술발표대회
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• pp.138-138
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• 2002

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2002년도 Join Meetings of Korean Society of Sericultural Science and Japanse Society of Sericultural Science
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• pp.145-145
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• 2002

No Abstract, See Full Text

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2000년도 잠사과학 100주년 국제심포지엄 및 추계학술대회
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• pp.61-61
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• 2000

No Abstract.See Full-text

• 대한의생명과학회지
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• 제24권1호
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• pp.23-29
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• 2018

Abdominal obesity is considered as one of the most risky factors governing the development of metabolic diseases. Here we identify that human chitinase 3-like 1 (CHI3L1, also called YKL-40 in human) single nucleotide polymorphism (SNP), rs883125, is associated with abdominal obesity in Korean women. Korean women subjects with the rs883125 G/G or C/G genotype present higher waist-hip ratio than subjects with C/C genotype suggesting that human subjects who G nucleotide substitution at the rs883125 tended to more accumulate intra-abdominal fat at the abdominal cavity. In addition, Chi3l1 gene expression is increased in adipose tissue from obese mice and pro-inflammatory cytokine enhances Chi3l1 expression in adipocytes, indicating that Chi3l1 is greatly related with obesity and obesity-induced pro-inflammatory responses. Taken together, the minor allele of rs883125 is associated with a higher prevalence of abdominal obesity in Korean women. These findings suggest that genotype of rs883125 can be a biomarker of incident abdominal obesity and abdominal obesity-related metabolic diseases.

• 한국환경농학회지
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• 제30권3호
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• pp.346-356
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• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.

• 한국유기농업학회지
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• 제30권3호
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• pp.393-407
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• 2022

본 논문에서는 Neobacillus sp. JC05의 추출물을 처리한 오이 식물체에서 고구마뿌리혹선충 감염에 대한 식물의 방어 반응을 조사하였다. Neobacillus sp. JC05의 추출물을 처리한 오이 식물체에서는 고구마뿌리혹선충에 의한 감염이 감소하여 control에 비하여 병 발생이 감소하였으며, 식물이 받는 피해도 줄어들었다. 이때 Neobacillus sp. JC05 추출물을 처리한 오이 식물체의 병 저항성 유전자의 발현량을 관찰한 결과, chitinase와 lipoxygenase 유전자의 발현량이 상대적으로 증가하였으며, 식물체 내 산화 스트레스를 감소시키는 항산화효소 중 peroxidase의 활성이 현저히 증가하는 것을 관찰하였다. 또한, Neobacillus sp. JC05 추출물을 처리한 오이 식물체의 토양 FDase 활성이 증가하였으며, 반면 인산가용화효소와 유레아제 활성은 control에 비해 유의하지 않았다. 그러므로, 이전의 연구 결과와 종합하면, Neobacillus sp. JC05의 추출물은 직접적으로 고구마뿌리혹선충의 알 부화율을 억제하고 유충의 사멸률을 높여 토양 내 고구마뿌리혹선충의 밀도를 감소시키기도 하지만 본 연구의 결과에 따르면, 오이 식물체의 고구마뿌리혹선충에 대한 방어 반응을 증가시켜 저항성을 유도하며, 이를 통해 고구마뿌리혹선충병 발생을 감소시키는데 기여하는 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.77-83
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• 1999

Molecular biological techniques that recently developed, have made it possible to realize some of new attempts in the research field of rumen microbiology. Those are 1) cloning of genes from rumen microorganisms mainly in E. coli, 2) transformation of rumen bacteria and 3) ecological analysis with nonculturing methods. Most of the cloned genes are for polysaccharidase enzymes such as endoglucanase, xylanase, amylase, chitinase and others, and the cloning rendered gene structural analyses by sequencing and also characterization of the translated products through easier purification. Electrotransformation of Butyrivibrio fibrisolvens and Prevotella ruminicola have been made toward the direction for obtaining more fibrolytic, acid-tolerant, depoisoning or essential amino acids-producing rumen bacterium. These primarily required stable and efficient gene transfer systems. Some vectors, constructed from native plasmids of rumen bacteria, are now available for successful gene introduction and expression in those rumen bacterial species. Probing and PCR-based methodologies have also been developed for detecting specific bacterial species and even strains. These are much due to accumulation of rRNA gene sequences of rumen microbes in databases. Although optimized analytical conditions are essential to reliable and reproducible estimation of the targeted microbes, the methods permit long term storage of frozen samples, providing us ease in analytical work as compared with a traditional method based on culturing. Moreover, the methods seem to be promissing for obtaining taxonomic and evolutionary information on all the rumen microbes, whether they are culturable or not.

• 한국토양비료학회지
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• 제43권4호
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• pp.490-497
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• 2010

근권토양으로부터 고추역병균을 포함한 다양한 식물 병원성 곰팡이에 대하여 항균활성이 강한 세균을 분리하였다. 이 세균은 16S rRNA gene서열 분석 결과 Lysobacter enzymogens로 동정되었고 LE429로 명명 하였다. LE429는 chitinase, ${\beta}-1$, 3-glucanase, protease, gelatinase, lipase 및 항생물질과 같은 다양한 이차대사산물을 분비하였다. 항생물질은 diaon HP-20 및 sephadex LH-20 컬럼크로마토그래피 및 HPLC로 정제하여, GC-EI 및 GC-CI분석을 통하여 phenylacetic acid로 동정되었다. Field 실험에서 LE429의 고추 병해 억제 효과를 조사하기 위해 LE429배양액(CB), Neem oil 용액 (NO), LE429배양액과 Neem oil 용액을 섞은 혼합액(CB+NO), 그리고 대조구로서 물(CON)을 각각 고추에 처리하였다. 고추의 수량구성요소는 일반적으로 CB 처리구가 가장 높았고, CB+NO, CON 그리고 NO 순서로 나타났다. CB 처리구에서 병원성 곰팡이는 강하게 억제 되었지만, 몇몇 해충이 발견되었다. NO 처리구에서는 해충은 발견 되지 않았지만, 병원성 곰팡이가 발견 되었다. 하지만, CB+NO 처리구에서 병원성 곰팡이 및 해충이 전혀 발견 되지 않았다. 결론적으로, 2차 대 사산물을 생산하는 LE429와 Neem oil의 혼합액은 고추에 발생하는 병원성 곰팡이와 해충에 대한 좋은 생물학적 방제제가 될 수 있다고 사료된다.