• Journal of Microbiology and Biotechnology
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• 제34권2호
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• pp.407-414
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• 2024

Phosphorus is an essential but non-renewable nutrient resource critical for agriculture. Luxury phosphorus uptake allows microalgae to synthesize polyphosphate and accumulate phosphorus, but, depending on the strain of algae, polyphosphate may be degraded within 4 hours of accumulation. We studied the recovery of phosphorus from wastewater through luxury uptake by an engineered strain of Synechocystis sp. with inhibited polyphosphate degradation and the effect of this engineered Synechocystis biomass on lettuce growth. First, a strain (∆phoU) lacking the phoU gene, which encodes a negative regulator of environmental phosphate concentrations, was generated to inhibit polyphosphate degradation in cells. Polyphosphate concentrations in the phoU knock-out strain were maintained for 24 h and then decreased slowly. In contrast, polyphosphate concentrations in the wild-type strain increased up to 4 h and then decreased rapidly. In addition, polyphosphate concentration in the phoU knockout strain cultured in semi-permeable membrane bioreactors with artificial wastewater medium was 2.5 times higher than that in the wild type and decreased to only 16% after 48 h. The biomass of lettuce treated with the phoU knockout strain (0.157 mg P/m²) was 38% higher than that of the lettuce treated with the control group. These results indicate that treating lettuce with this microalgal biomass can be beneficial to crop growth. These results suggest that the use of polyphosphate-accumulating microalgae as biofertilizers may alleviate the effects of a diminishing phosphorous supply. These findings can be used as a basis for additional genetic engineering to increase intracellular polyphosphate levels.

• 천문학회보
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• 제46권2호
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• pp.75.2-76
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• 2021

MESSIER is a science satellite project to observe the Low Surface Brightness (LSB) sky at UV and optical wavelengths. The wide-field, optical system of MESSIER is optimized minimizing optical aberrations through the use of a Linear Astigmatism Free - Three Mirror System (LAF-TMS) combined with freeform mirrors. One of the key factors in observations of the LSB is the shape and spatial variability of the Point Spread Function (PSF) produced by scatterings and diffraction effects within the optical system and beyond (baffle). To assess the various factors affecting the PSF in this design, we use PhoSim, the Photon simulator, which is a fast photon Monte Carlo code designed to include all these effects, and also atmospheric effects (for ground-based telescopes) and phenomena occurring inside of the sensor. PhoSim provides very realistic simulations results and is suitable for simulations of very weak signals. Before the application to the MESSIER optics system, PhoSim had not been validated for confocal off-axis reflective optics (LAF-TMS). As a verification study for the LAF-TMS design, we apply Phosim sequentially. First, we use a single parabolic mirror system and compare the PSF results of the central field with the results from Zemax, CODE V, and the theoretical Airy pattern. We then test a confocal off-axis Cassegrain system and check PhoSim through cross-validation with CODE V. At the same time, we describe the shapes of the freeform mirrors with XY and Zernike polynomials. Finally, we will analyze the LAF-TMS design for the MESSIER optical system.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2729-2734
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• 2012

Despite clinical advances in anticancer therapy, there is still a need for novel anticancer metabolites, with higher efficacy and lesser side effects. Oroxylum indicum (L.) Vent. is a small tree of the Bignoniaceae family which is well known for its food and medicinal properties. In present study, the chemopreventive properties of O. indicum hot and cold non-polar extracts (petroleum ether and chloroform) were investigated with MDA-MB-231 (cancer cells) and WRL-68 (non-tumor cells) by XTT assay. All the extracts, and particularly the petroleum ether hot extract (PHO), exhibited significantly (P<0.05) higher cytotoxicity in MDA-MB-231 when compared to WRL-68 cells. PHO was then tested for apoptosis induction in estrogen receptor (ER)-negative (MDA-MB-231) and ER-positive (MCF-7) breast cancer cells by cellular DNA fragmentation ELISA, where it proved more efficient in the MDA-MB-231 cells. Further, when PHO was tested for anti-metastatic potential in a cell migration inhibition assay, it exhibited beneficial effects. Thus non-polar extracts of O. indicum (especially PHO) can effectively target ER-negative breast cancer cells to induce apoptosis, without harming normal cells by cancer-specific cytotoxicity. Hence, it could be considered as an extract with candidate precursors to possibly harness or alleviate ER-negative breast cancer progression even in advanced stages of malignancy.

• 수완나부미
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• 제13권2호
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• pp.37-67
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• 2021

Mazu is considered the famous Chinese Sea Goddess, venerated by seafarers. Mazu belief was conducted in Meizhou County, Fujian Province. Soon worship of Mazu spread quickly to other parts of over the world, especially in Southeast Asia. In China, the Mazu belief was strongly influenced by marine culture, but its marine factors faded when Chinese immigrants had lived together with the Kinh people in Pho Hien (in the north of Vietnam) for more than four centuries. Applying the Acculturation theory, this paper aims to analyze the migration background of the Chinese and their integration into Kinh culture in Pho Hien. It can be said that historical, economic and social context, as well as native government policies have highly affected the manner and the rate of this belief's acculturation. Furthermore, the article explains the reasons for the fading of marine cultural traits and their replacement by the Kinh people's cultural factors in this belief.

• 자연과학논문집
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• 제11권1호
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• pp.65-73
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• 1999

C-P 화합물(Pn; phosphonate)의 일종인 glyphosate(GPS)를 인산원으로 이용하는 Pseudomonas sp. strain #A1으로부터 GPS 분해 유전자 및 2-aminoethylphosphonate(AEPn), methyl-phosphonate(MPn)와 같은 Pn의 분해 유전자를 클로닝하였다. Mini-Mu plasmid를 이용한 in vivo molecular cloning 결과 약 10-19 Kb의 $AEPn^+$ clones, 10 Kb의 $MPn^+$ clones, 12-18 Kb의 $GPS^+$ clone들을 얻었으며 E. coli의 $\Delta phn$ mutants에 transformation 하였을 때 각각의 Pn에 대한 다양한 phenotype을 나타냈다. 따라서 Pseudomonas sp. strain #A1에서는 적어도 3종류의 Pn 분해대사 경로를 갖고 있는 것으로 예측된다. 뿐만 아니라, 각각의 phn clone($AEPn^+$, $MPn^+$, $GPS^+$)들은 PHO regulon의 조절유전자 phoBR에 의존하여 발현하였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.264-264
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• 1999

No Abstract, See Full Text

• 한국균학회지
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• 제41권1호
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• pp.52-55
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• 2013

Phoma glomerata는 식물 잎이나 열매에 병을 일으키는 식물병원균으로 알려져 있다. 국내에서는 아직 피해사례가 없기 때문에 P. glomerata는 국내의 식물검역균으로 관리되고 있다. 본 연구는 국내에 들어오는 목재나 과일에 P. glomerata를 검출할 수 있는 방법 개발코자 수행되었다. Phoma 균주들의 translation elongation factor 1 alpha 유전자 염기서열에 기초하여 P. glomerata 특이적 PCR 프라이머를 디자인 하였고 그 특이성을 검정하였다. PCR 수행 결과 P. glomerata에서만 170 bp 크기의 밴드가 증폭되었고, 다른 비교 균주에서는 밴드가 증폭되지 않았다. 검출 감도를 평가하기 위해 기존 PCR방법과 real time PCR 방법을 이용하여 실험한 결과 최소 10 pg과 1 pg까지 각각 검출할 수 있었다. 본 연구결과는 디자인된 PCR 프라이머가 P. glomerata를 특이적으로 검출하는데 유용할 것임을 보여준다.

• Journal of Microbiology and Biotechnology
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• 제5권3호
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• pp.125-131
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• 1995

A 3, 346 bp of the cdd upstream region in Bacillus subtilis was sequenced from the pSO1 (Song BH and J Neuhard. 1989. Mol. Gen. Genet 216: 462-468) and sequence homology was searched to the known genes in Genbank and European Molecular Biology Laboratory databanks. Five complete and one truncated putative coding sequences deduced from the nucleotide sequence were found through the ORF searching by Genetyx and Macvector software, and one of them was identified as the dgk (diacylglycerol kinase) gene and another, a truncated one, as the phoH (phosphate starvation-inducible gene) gene. The B. subtilis dgk gene, having a role for response to several environmental stress signals, revealed an open reading frame of 134 amino acids with 43.1% of sequence identity to the Streptococcus mutans dgk gene. The carboxy terminal 59 residues of the truncated phoH gene showed 52.7% and 34.5% of sequence identity in amino acids with the corresponding genes of Mycobacterium leprae and Escherichia coli. The four remaining coding sequences consisting of 115, 421, 91, and 91 residues were thought to be unknown ORFs because they have no significant similarity to known genes.

• 생명과학회지
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• 제19권5호
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• pp.566-572
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• 2009

S. marcescens KCTC 2172로부터 유전자 은행을 작성하여 재조합 클론 pDH3를 얻었으며, pDH3 유래의 서브클론을 작성하였다. 플라스미드 pPH4의 전염기서열 5,137 bp 영역을 결정한 결과 3개의 ORF가 있음을 확인하였다. 이들은 pst 오페론의 pstC, pstA, 및 pstB, 세 유전자를 동일 전사방향으로 코드하고 있었다. 타 세균의 유전자와 비교한 결과 S. marcescens의 pst 오페론은 pstS와 phoU가 결손되어 있다. 조절영역에는 CRP 결합영역과 pho box 서열이 존재하였다. 보고된 유전자와 상동성 조사결과, PstC 단백질은 Yersinia sp., Vibrio sp. 및 Pseudomonas sp.와는 49, 37, 33%의 상동성을, PstA 단백질은 Yersinia sp., Vibrio sp. 및 Pseudomonas sp.와 64, 51, 47%의 상동성을, PstB 단백질은 Methanocaldococcus sp., E. coli 및 Mycoplasma sp.와 60, 50, 48%의 상동성을 나타내었다. Pst 유전자들은 조절영역의 cAMP-CRP 복합체에 의해 in vivo에서 양성적으로 발현됨을 확인하였다. Pst 오페론을 포함하는 플라스미드를 도입한 대장균은 인산운송에 관여하는 능력을 확인하였다.

• 대한수의학회지
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• 제35권3호
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• pp.531-536
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• 1995

Salmonella species are the most prevalent etiologic agents of food-borne acute gastroenteritis. Direct isolation of bacteria from the contaminated food, stool and animal tissues has been used for the diagnosis of salmonellosis routinely. However, isolation of bacteria is time consuming work and not so highly sensitive. In recent years, improved methods of polymerization chain reaction(PCR) and probe hybridization technique have led to the developement of diagnostic assays which employ to detect various human and animal pathogenic bacteria. In this study, we have performed the polymerization chain reaction to detect Salmonella pullorum from tissues and stool samples of chickens with two specific primers, ST5 and ST8C. The target DNA fragment of PhoE gene was successfully amplified from liver, spleen, pancreas, heart, lung, ovary, oviduct and feces samples. The amplified DNA fragments were hybridized with Salmonella typhymurium TA3000 PhoE probe by Southern hybridization. The PCR to amplify the PhoE gene was highly rapid and sensitive method to detect Salmonella pullorum from tissues and stool samples.