• 생명과학회지
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• 제19권8호
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• pp.1132-1138
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• 2009

해양세균 Pseudoalteromonas psicida TA20의 ethanol 색소 추출물에 대한 안정성과 기능성을 검토한 결과, 본 해양세균 색소는 pH 4.0에서 pH 8.0의 조건과 $40^{\circ}C$ 이하에서 매우 안정하였으며, $25^{\circ}C$ 14일간 90% 이상의 잔존율을 나타내어 빛에 대한 안정성이 매우 우수한 것으로 나타났다. 금속이온의 경우 $Al^{3+}$과 $Cu^{2+}$를 제외한 실험된 모든 금속이온에 대하여 매우 안정하였으며 특히, 다른 색소추출물들에 비해 $Fe^{2+}$에 대한 안정성이 높은 것으로 나타났다. 해양세균 색소추출물에 대한 생리활성 실험 결과, free radical 소거 활성 (3495 ${\mu}g/ml$)이 나타났으며, 색소농도 10 ${\mu}g/ml$일 때 44%의 인체세포 DNA 손상 회복능이 있음을 보여 항산화능이 우수함을 알 수 있었다. 또한 주요 식품유해세균에 대하여 항균활성을 나타내었다. 따라서 본 해양세균 색소는 항산화능과 항균활성을 갖는 식품 색소로의 적용을 검토할 수 있을 것으로 기대된다.

• 식물병연구
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• 제10권4호
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• pp.310-312
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• 2004

Pseudomonas syringae pv. actinidiae는 참다래 궤양병을 일으키는 세균이다. 식물독소인 coronatine 생합성에 관여하는 유전자 중 하나인 cfl의 염기서열로부터 설계된 primer를 사용한 nested PCR 방법을 토양시료에 적용시켰다. 이 primer 세트와 우리나라에서 분리된 P. syringae pv. actinidiae가 접종된 토양으로부터 얻은 DNA로 두 번의 PCR을 행했을 때 665 bp와 310 bp의 절편이 각각 증폭되었다. 이 시스템을 참다래 궤양병으로 폐원된 과수원의 토양조사에 적용시킨 결과 여섯 곳으로부터 채취한 토양시료 모두에서 특이적인 310 bp의 PCR 산물이 증폭되었다.

• 대한수의학회지
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• 제49권4호
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• pp.319-328
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• 2009

This study investigated the epidemiology of Listeria (L.) monocytogenes, a food-borne pathogen. The epidemiology of food-borne pathogens is of great importance for clarifying bacterial origin and preventing bacterial contamination and infection. This work examined 68 L. monocytogenes strains, including 11 reference strains and 57 isolates from imported US beef, domestic meats (beef, pork, chicken meat), raw milk, and milk plants. The random amplified polymorphic DNA (RAPD) techniques were optimized to develop a standard molecular epidemiological analysis of L. monocytogenes. There was great genetic variability among the isolates, which produced 24 and 34 RAPD patterns with primer HLWL85 and HLWL74, respectively. The discriminatory power of the RAPD methods with HLWL85 and HLWL74 primer were very high (DI = 0.957; S ${\geq}$ 80%, S ${\geq}$ 95%). Some RAPD types were specific to origin. A few RAPD types were specific for L. monocytogenes strains belonging to a particular serotype. Using the HLWL85 primer, the strains isolated from milk plants could be distinguished from the other strains. And using the HLWL74 primer, the strains isolated from imported beef (US) could be distinguished completely from the other strains.

• 식물병과 농업
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• 제5권1호
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• pp.1-7
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• 1999

The grain rot of caused by Bukholderia glumae was fist reported in japan in 1955 and then reported in other countries as well as in Korea in 1986. The pathogen causes both seedling and grain rot of rice but it cannot attack any other parts of adult rice plant. Bacterial colonies grow slowly, and are circular and greyish white. The causal bacterium is Gram-negative and rod shape with 1-3 polar flagella, and produce a diffusible yellow-greenish nonfluorescent pigment on King's medium B. Biochemical characteristics such as negative in arginine dehydrolase, oxidase reaction and nitrate reduction and positive in lecithinase, and the utilization of L-arginine and inositol are useful in differentiation of this from other nonfluorescent bacteria pathogenic to rice. This pathogenic bacterium had belonged to the genus of Pseudomonas but recently was transferred to the new genus Burkholderia on the basis of physiological characteristics and DNA-DNA hybridization data. However, other characteristics such as colony heterogenicity or colonial variation after subcultures, phytotoxin, secreting antibiotics, and relationship between yellow greenish pigment production and pathogenicity need to be clarified more. To develop an effective control strategy for this disease, understanding of detailed life cycle of the disease and critical environmental factors affecting disease development is prerequisite. Although 5,435 ha of rice paddy in Korea was infested during 1998, there is no exact estimation of yield losses and distribution of the pathogen. The review will focus on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.

• Fisheries and Aquatic Sciences
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• 제18권2호
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• pp.173-181
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• 2015

We identified the $Na^+-K^+-2Cl^-$ cotransporter 2 (NKCC2) cDNA isoform from starry flounder, Platichthys stellate. The NKCC2 cDNA encoded a polypeptide of 1,043 amino acids representing 12 putative transmembrane domains based on the bioinformatic topology prediction. In addition, starry flounder NKCC2 possessed highly conserved residues within transmembrane domain 4, known as an essential site for its function. End-point reverse transcription-polymerase chain reaction analysis revealed that the NKCC2 transcript was moderately expressed only in the anterior and posterior intestines and the rectum. The NKCC2 mRNA level in the rectum, but not in other segments, was significantly induced 3 days post Streptococcus parauberis challenge, indicating that excess salt may be transported into the rectum. Taken together, our data indicate that an S. parauberis infection could tip the intestinal fluid balance in favor of fluid accumulation, indicating that bacterial pathogens can interfere with intestinal osmotic balance and normal mucosal immune homeostasis.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.423-427
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• 2004

Seventy-six animals including cattle, sheep, horses, 6 species of zoo animals were employed for collection of fresh feces in order to detect verotoxigenic Esherichia coli (VTEC) by safe, quick and sensitive PCR-based molecular methods. Bacterial cell disruption with bead-beating followed by bacterial DNA purification with hydroxyapatide chromatography and gel filtration allowed DNA preparation from animal feces with high recovery and purity. A mountain goat was firstly shown by PCR and sequencing to shed verotoxin 2 gene (vt2) that was used to generate vt2 probe and second primer set for nested PCR to attempt more sensitive detection. Most sensitive nested PCR revealed that 45% of tested cattle and 47% of tested zoo animals were VTEC-positive, while least sensitive normal PCR detected VTEC from none of these animals except a mountain goat. Moderately sensitive detection by PCR in combination with hybridization suggested that the VTEC density varied between the VTEC-positive cattle.

• The Plant Pathology Journal
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• 제32권2호
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• pp.162-167
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• 2016

Pseudomonas syringae pv. actinidiae, the causal agent of canker in kiwifruit, can be divided into three biovars (biovars 1, 2, and 3). Strains belonging to biovar 1 produce phaseolotoxin and were isolated in Japan and Italy before 2008. Strains of biovar 2 produce coronatine instead of phaseolotoxin and have been isolated only in Korea. Strains belonging to biovar 3 produce neither phaseolotoxin nor coronatine and are responsible for the global outbreak of bacterial canker of kiwifruit in recent years. The biovar 3-specific primer set was developed in a previous work. In this study, two sets of PCR primers specific to strains of biovars 1 and 2, respectively, were developed based on random amplified polymorphic DNA analyses. Primers PsaJ-F and PsaJ-R produced a 481-bp region with genomic DNA of biovar 1 strains, whereas primers PsaK-F and PsaK-R amplified a 413-bp region present only in the genome of biovar 2 strains.

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.202-210
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• 2007

A total of 45 bacterial strains were isolated from the traditional Korean soybean-fermented food, Chungkookjang. Among these strains, seven strains were selected and identified based on morphological, physiological, and biochemical characteristics, as well as phylogenetic analysis using 16S rDNA sequences. All strains were Gram-positive, aerobic, motile, oxidase-positive, rod-shaped, and endospore-forming bacteria, and produced extracellular enzymes such as amylase, cellulase, lipase, protease, and xylanase. The isolates were grown in the presence of 0-11% (w/v) NaCl. Growth was optimal at pH 6-9 and at temperatures of $30-45^{\circ}C$. According to VITEK automicrobic system tests and supplementary tests, the isolates were similar to several species of the genus Bacillus. The phylogenetic analysis of seven bacterial strains based on comparisons of 16S rDNA sequences, revealed that the strains were closely related to Bacillus species. The identification of strains that produced surfactin was also carried out, based on PCR screening of the sfp gene. Among the seven isolated strains, six yielded a surfactin-positive result with PCR.

• Journal of Microbiology
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• 제43권5호
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• pp.383-390
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• 2005

The diversity of the denitrifying bacterial populations in Daejeon Sewage Treatment Plant was examined using a culture-dependent approach. Of the three hundred and seventy six bacterial colonies selected randomly from agar plates, thirty-nine strains that showed denitrifying activity were selected and subjected to further analysis. According to the morphological and biochemical properties, the thirty nine isolates were divided into seven groups. This grouping was supported by an unweighted pair group method, using an arithmetic mean (UPGMA) analysis with fatty acid profiles. Restriction pattern analysis of 16S rDNA with four endonucleases (AluI, BstUI, MspI and RsaI) again revealed seven distinct groups, consistent with those defined from the morphological and biochemical properties and fatty acid profiles. Through the phylogenetic analysis using the 16S rDNA partial sequences, the main denitrifying microbial populations were found to be members of the phylum, Proteobacteria; in particular, classes Gammaproteobacteria (Aeromonas, Klebsiella and Enterobacter) and Betaproteobacteria (Acidovorax, Burkholderia and Comamonas), with Firmicutes, represented by Bacillus, also comprised a major group.

• 식물병연구
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• 제24권4호
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• pp.339-341
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• 2018

Amaranth has the potential for good materials related to nutrients and health benefits. There are several diseases of amaranth such as leaf blight, damping-off, and root rot. As a causal agent of soft rot disease, Pectobacterium spp. could infect various plant species. In this study, we isolated the bacterial pathogen causing soft rot of amaranth in South Korea. In Gangneung, Gangwon province during 2017, amaranth plants showed typical soft rot symptoms such as wilting, defoliation and odd smell. To isolate pathogen, the macerated tissues of contaminated amaranth were spread onto LB agar plates and purified by a single colony subculture. One ml bacterial suspension of a representative isolate was injected to the stem of five seedlings of 2-week-old amaranth with a needle. Ten mM magnesium sulfate solution was used as a negative control. 16S rDNA gene and recA gene were sequenced and compared with the reference sequences using the BLAST. In the phylogenetic tree based on 16S rDNA gene and recA gene, GSA1 strain was grouped in Pcb.