• Journal of Microbiology and Biotechnology
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• 제6권5호
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• pp.326-330
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• 1996

To illustrate whether a hemolysin in $\delta$-endotoxins of Bacillus thuringiensis strain 73E10-2 and subsp. israelensis had immunological identity, a cyt gene of the strain 73E10-2 which encodes a hemolysin was cloned to B. subtilis (transformant 2753). The transformant 2753 containing cyt gene produced the hemolysin which lysed sheep erythrocytes after treatment of proteinase K. The hemolysin was proved also to be toxic against mosquito larvae (Aedes aegypti). The molecular weight of the hemolysin produced from the transformant 2753 was determined to be about 25 kDa by SDS-PAGE and immunoblot. The hemolysin in $\delta$-endotoxin of subsp. israelensis and subsp. kyushensis did not react on immunoblot using polyclonal anti-$\delta$-endotoxin of the strain 73E10-2, but 70-140 kDa mosquitocidal toxins in $\delta$-endotoxin of subsp. kyushuensis reacted.

• 한국미생물·생명공학회지
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• 제20권3호
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• pp.301-310
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• 1992

요로계 감염에 대처함에 있어 hemolysin과 Gal-Gal pili의 multicomponent 백신 개발 가능성을 조사하기 위하여 본 연구를 수행하였다. 요로계 감염환자로부터 분리되어 그의 hemolysin gene 의 염기배열과 아미노산 배열이 밝혀진 대장균 J96 균중의 hemolysin에 대하여 10곳에 해당하는 20 mer-oligonucleotide를 합성하였다. 이들 probe를 사용하여 요로계감염 환자들로부터 분리한 wild type 대장균들의 DNA에 대하여 hemolysin gene 의 상동성을 조사하였는 바 8개의 probe는 거의 모든 hemolysin signal을 보여주었고 HA484는 28.3, HA661은 71.7의 positive signal을 나타내었다.이는 요로계 감염 대장균들의 Hemolysin gene의 상동성이 매우 높은 것을 의미한다. 또한 J96 hemolysin에 대한 12개의 MAB은 모두 wild type 대장균들이 분비하는 90% 이상의 균주에 대하여 양성 immunoblotting을 나타내었다. 특히 J96 hemolysin의 functional site를 가장 강력하게 block할 수 있는 monoclonal antibody MAＢ132가 모든 wild type으로부터 분리된 hemolysin의 function을 중화시킬수 있는 결과는 J96의 cloned hemolysin product를 vaccine으로 사용할 수 있는 가능성을 증대시키는 결과라고 할 수 있다.

• 한국수산과학회지
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• 제30권6호
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• pp.1056-1057
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• 1997

• 한국수산과학회지
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• 제53권5호
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• pp.752-760
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• 2020

Acute hepatopancreatic necrosis disease (AHPND), previously known as early mortality syndrome (EMS), is an emerging disease in shrimp caused by Vibrio parahaemolyticus. Some V. parahaemolyticus strains are associated with foodborne diseases in humans. To date, studies on the relationship between AHPND and pathogenic V. parahaemolyticus are very limited. In this study, we monitored the thermostable direct hemolysin-related hemolysin (trh) gene and AHPND-related genes, such as Photorhabdus insect-related (pir) genes, in 892 strains of V. parahaemolyticus isolated and identified in 24 areas of the West Coast of Korea from May to October 2019. The trh gene was detected in 9.6% of the isolates from short neck clam samples. However, the pirA and pirB genes related to AHPND were not found in any of the isolates despite using both duplex and nested PCR assays, suggesting that AHPND-related genes were nonexistent in the V. parahaemolyticus strains isolated. This study contributes to the current understanding of the relationship between AHPND and V. parahaemolyticus in Korea, as well as provides data on spatial and seasonal distributions of V. parahaemolyticus.

• 한국미생물·생명공학회지
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• 제30권3호
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• pp.230-234
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• 2002

모기 살충성 Bacillus thuringiensis subspangiensis 21-2균주의 용혈성 내독소 단백질의 특성을 검토하고자 21-2균주의 용혈성을 가진 유전자를 Escherichia coli HBIO쎄 형질전환시켰다. 이들 중에서 형질전환 균주 47은 독소 단백질을 생산하며 2.5 kb DNA을 함유한다는 것을 효소항체법, immunoblot및 DNA전기영동법으로 확인하였다. 또한, 형질전환 균주 47-5는 2.5 kb DNA를 다시 Hind ll견 절단하여 pUC118 연결시켜서 조제하였다 그 결과형질전환 균주 47-5은 1.Bkb DNA를 함유하며, 23 kD꺼 독소 단백질을 발현하고, 발현된 독소 단백질은 Aedes aegypti모기 유충에 독성을 나타내었다. 또한 23 kDa의 내독소 단백질 그 자체로는 사람의 적혈구를 용해하지 못하였으나, proteinase K로 처리한 후에는 적혈구에 대해 용혈성을 나타내었다.

• 한국임상수의학회지
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• 제27권1호
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• pp.62-65
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• 2010

Arowana (Scleropages formosus) is the most valuable group of ornamental fishes and very much in demand in the ornamental fish trade and commands high price ranging from hundreds to thousands of dollars per fish. In this paper, we described a case of mortality of arowana from a private aquarium in Korea. A bacterial pathogen from fish organs (brain, kidney, liver) was cultured, identified and confirmed using Vitek System 2, API 20E test, multiplex PCR and 16S rRNA gene sequencing. The morphological and biochemical properties of the bacterium isolated from the brain, kidney and liver of the fish were similar to Aeromonas sobria. Positive amplification products using the multiplex PCR assay for detection of A. sobria were obtained from these organs. The 16S rRNA gene of the isolates from fish was identical and exhibited 100% sequence similarity with A. sobria (AY987762.1) strain available from GenBank. This bacterium contained hemolysin gene, a virulence factor that plays an important role in outbreaks of disease and is pathogenic to humans as well as in fish. Although this opportunistic bacterium was isolated from a fish without any external symptoms, this pathogen may act as a reservoir and enhance chances of zoonosis to human such as during handling.

• 대한수의학회지
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• 제50권4호
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• pp.331-333
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• 2010

Moribund albino catfish, Clarias sp., displayed from an indoor private commercial aquarium were submitted in the laboratory for diagnostic examination. Dense culture of bacteria was recovered from the kidney and was characterized using Vitek System 2 and showed 98% probability to Aeromonas (A.) hydrophila. PCR result showed positive using A. hydrophila extracellular hemolysin gene ahh1 (130 bp) and aerolysin gene aerA (309 bp). The 16S rRNA gene was identical and exhibited 97% sequence similarity with the other known isolates of A. hydrophila available in the GenBank. In this paper, we reported the isolation and molecular detection of A. hydrophila from an albino catfish.

• 한국식품위생안전성학회지
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• 제23권3호
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• pp.248-256
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• 2008

본 연구는 축산물 유래 L. monocytogenes에 대한 역학적 연구로서 분리균의 hemolysin(LLO) 및 lecithinase(LCP)생산성, Congo red dye(CRA)흡수성 및 hemolysin activity를 조사하는 한편 inlA, inlBV, actA, hlyA, plcA 및 plcB의 virulence gene을 PCR법으로 분석하였다. LLO, LCP 및 CRA의 양성률은 L. monocytogenes의 경우 68균주 중 각각 100%, 94.1% 및 77.9%이었고, L. ivanovii와 L. seeligeri를 제외한 다른 Listeria spp.(L. innocua, L. gray, L. murrayi, L. welchimeri)는 음성이었다. LLO와 LCP간에는 통계적인 유의성은 없었으나 CRA는 약간 낮게 나타났으며(p<0.05), serotype 1/2b 및 4b 간에도 유의성이 인정되지 않았다. 면양적혈구에 대한 용혈성(MHU)에서 L. monocytogenes의 경우 2배에서 16배까지 다양한 반응을 보였으나 L. ivanovii와 L. seeligeri를 제외한 다른 Listeria spp.는 음성이었다. hemolysin activity(HU)는 L. monocytogenes의 경우 대부분의 균주가 1.0 HU/mg 이상이었으나 다른 Listeria spp.는 대부분 0.04 HU/mg 이하였다. PCR 증폭하여 virulence gene을 분석한 결과 모든 L. monocytogenes는 각기 예상한 크기의 PCR 증폭산물이 검출되어 hlyA, plcA, plcB, inlA 및 inlB gene을 보유하고 있음이 확인되었으나 다른 Listeria spp.는 어떠한 증폭산물도 보이지 않았다. 또한 actA gene에 대한 증폭산물은 385bp와 268bp 크기의 2종류로 각각 57.4%와 42.6%의 분포를 나타내었다. actA gene의 size 분포에서 국내산 쇠고기, 닭고기, 유가공장에서는 큰 size가 많았는데 반하여 미국산 수입쇠고기에서는 작은 size가 많은 것으로 나타났다.

• 한국수산과학회지
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• 제49권2호
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• pp.116-123
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• 2016

This study investigated the prevalence of Vibrio parahaemolyticus in the oyster Crassostrea gigas, which is commonly consumed raw. The presence of virulence factors and the antimicrobial susceptibility of isolates were also investigated. The overall prevalence rate of V. parahaemolyticus in oysters was 37.5% (36/96) and the range of concentrations was 30-11,000 MPN/100 g. PCR-based assays indicated that 9.6% (11/115) of the isolates were positive for the thermostable direct hemolysin-related hemolysin gene (trh), while none of the isolates were positive for the thermostable direct hemolysin gene (tdh). The Multiple Antibiotics Resistance (MAR) index was measured for 16 common antimicrobial agents and 46.1% (53/115) of the isolates had a MAR index > 0.2. The MAR index ranged from 0.07 to 0.73. The highest MAR index was observed with strain s150608, isolated in June 2015, which exhibited resistance to 11 antimicrobial agents. Our results demonstrate that oysters are high-risk sources of V. parahaemolyticus, although no antimicrobial agent was being used to promote growth or to treat bacterial infections in the sampled oyster-growing areas.

• 한국수산과학회지
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• 제49권4호
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• pp.460-466
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• 2016

From 2013 through 2015, we investigated the contamination status and antimicrobial resistance patterns of pathogenic Vibrio parahaemolyticus in commercially valuable seawater and shellfish (Oyster Crassostrea gigas, short-neck clam Venerupis philippinarum, ark shell Scapharca broughtonii and mussel Mytilus galloprovinciallis) from the southern coast of Korea. The detection rate of V. parahaemolyticus was highest in short-neck clams (23.7%), followed by ark shells (19.2%), oysters (15.9%), mussels (13.6%), and seawater (8.6%). The following percentages of PCR assays of shellfish were positive for the thermostable direct hemolysin-related hemolysin gene (trh) : oysters (12.8%), short-neck clams(11.8%), and ark shells (3.4%). Similar assays for the thermostable direct hemolysin gene (tdh) resulted in positive results for short-neck clams (5.9%) and ark shells (3.4%). Antimicrobial resistance was present in 100% of 8 tdh (+) and 2 trh (+) V. parahaemolyticus isolates challenged with ampicillin. However, all pathogenic V. parahaemolyticus were sensitive to 14 other antibiotics. To ensure the safety of shellfish consumption, the continuous monitoring of the prevalence and distribution of virulence factors of V. parahaemolyticus in shellfish farms is needed.