• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1299-1309
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• 2019

As an opportunistic bacterial pathogen, Pseudomonas aeruginosa PAO1 contains two phenazine-producing gene operons, phzA1B1C1D1E1F1G1 (phz1) and phzA2B2C2D2E2F2G2 (phz2), each of which is independently capable of encoding all enzymes for biosynthesizing phenazines, including phenazine-1-carboxylic acid and its derivatives. Other previous study reported that the RpoS-deficient mutant SS24 overproduced pyocyanin, a derivative of phenazine-1-carboxylic acid. However, it is not known how RpoS mediates the expression of two phz operons and regulates pyocyanin biosynthesis in detail. In this study, with deletion of the rpoS gene in the $PA{\Delta}phz1$ mutant and the $PA{\Delta}phz2$ mutant respectively, we demonstrated that RpoS exerted opposite regulatory roles on the expression of the phz1and phz2 operons. We also confirmed that the phz1 operon played a critical role and especially biosynthesized much more phenazines than the phz2 operon when the rpoS gene was knocked out in P. aeruginosa. By constructing the translational reporter fusion vector lasR'-'lacZ and the chromosomal fusion mutant $PA{\Delta}lasR::lacZ$, we verified that RpoS deficiency caused increased expression of lasR, a transcription regulator gene in a first quorum sensing system (las) that activates overexpression of the phz1 operon, suggesting that in the absence of RpoS, LasR might act as an intermediate in overproduction of phenazine biosynthesis mediated by the phz1 operon in P. aeruginosa.

• 대한한의학회지
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• 제32권1호
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• pp.130-140
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• 2011

Objectives: This study was performed in order to investigate the anti-hemolytic effect of Chunghyuljihwang-tang(CHJHT, Qingxuedihuang-tang) on phenylhydrazine-induced hemolytic anemia in Rats. Materials and Methods: Hemolytic anemia model of rats were induced by phenylhydrazine(PHZ, 40mg/kg/day, i.p.) for 3days. Male Sprague-Dawley rats were divided into three groups for their treatment. Normal group was injected normal saline for 3 days with distilled water(d.w.) orally, control group was injected PHZ for 3 days with d.w. and CHJHT group was injected PHZ for 3 days with administration of CHJHT for 10 days. RBC(Red blood cell), Hb(hemoglobin), mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, reticulocyte were determined on day 0, 4, 7, 10. Body weight was investigated on day 0, 2, 4, 6, 8, 10 and the weight of spleen was measured on day 10. Results: For CHJHT group, the levels of RBC and Hb were significantly higher than control group on day 4, and the concentration of hemoglobin on day 7 was increased more than control group. Moreover, reticulocyte was significantly decreased on day 10 more than control group. These results could be concluded that CHJHT suppressed the hemolytic anemia by PHZ and improved hematological values of anemia earlier.

• Journal of Microbiology and Biotechnology
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• 제22권3호
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• pp.326-330
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• 2012

Antifungal metabolites were isolated from a culture of Pseudomonas aurantiaca IB5-10. Chemical structures of the metabolites were elucidated as phenazine-1-carboxylic acid (PCA; 1), 2-hydroxyphenazine (2-OH-PHZ; 2), and cyclo-(L-Pro-L-Val; 3), respectively, based on spectroscopic methods. Among them, 3 was isolated for the first time from this strain. The antifungal activities of 1-3 were evaluated against a variety of plant pathogens. To the best of our knowledge, the antifungal activities of 3 against plant fungal pathogens have been evaluated for the first time in this work. PCA (1) showed the most potent antifungal activities against Phytophthora capsici, Rhizoctonia solani AG-1(IA), and Pythium ultimum with MICs (${\mu}g/ml$) of less than 1.0, 1.3, and 2.0, respectively. On the other hand, 2-OH-PHZ (2) showed potent antifungal activity against R. solani AG-1(IA) with the MIC (${\mu}g/ml$) of 2.0, whereas it showed moderate antifungal activity against P. ultimum with the MIC (${\mu}g/ml$) of 50.0. In addition, 3 showed antifungal activity against only R. solani AG-1(IA).

• 한국동물학회:학술대회논문집
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• 한국동물학회 1996년도 한국생물과학협회 국제학술대회
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• pp.155.1-155
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• 1996

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.202.1-202
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• 1997

No Abstract, See Full Text

• 인간식물환경학회지
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• 제24권5호
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• pp.519-527
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• 2021

Background and objective: This study was conducted to establish a Plant Hardiness Zone (PHZ) map, investigate the effect of global warming on changes in PHZ, and elucidate the difference in the distribution of evergreen trees between the central and southern region within hardiness Zone 7b in Korea. Methods: Mean annual extreme minimum temperature (EMT) and related temperature fluctuation data for 40 years (1981 to 2020) in each of the meteorological observation points were extracted from the Open MET Data Portal of the Korea Meteorological Administration. Using EMT data from 60 meteorological observation points, PHZs were classified according to temperature range in the USDA Plant Hardiness Zone Map. Changes in PHZs for each decade related to the effects of global warming were analyzed. Temperature fluctuation before and after the day of EMT were analyzed for 4 areas of Seoul, Suwon, Suncheon, and Jinju falling under Zone 7b. For statistical analysis, descriptive statistics and ANOVA were performed using the IBM SPSS 22 Statistics software package. Results: Plant hardiness zones in Korea ranged from 6a to 9b. Over four decades, changes to warmer PHZ occurred in 10 areas, especially in colder ones. Based on the analysis of daily temperature fluctuation, the duration of sub-zero temperatures was at least 2 days in Seoul and Suwon, while daily maximum temperatures were above zero in Suncheon and Jinju before and after EMT day. Conclusion: It was found that the duration of sub-zero temperatures in a given area is an important factor affecting the distribution of evergreen trees in PHZ 7b.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.240.2-240
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• 1998

No Abstract, See Full Text

• 식물조직배양학회지
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• 제26권2호
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• pp.121-126
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• 1999

참나물 (Pimpinella brachycarpa)의 엽병 (petiole)절편체로부터 캘러스가 MS배지 (0.5mg/L 2,4-D와 0.1mg/L BAP)에서 유도되었으며 이들 캘러스로부터 치밀하게 배열된 세포집단(cell cluster)을 선발하여 현탁배양하였다. 이들 현탁배양세포들은 0.1 mg/L NAA가 포함된 MS고체배지에 배양되어 배발생 (embryogenic) 캘러스로 성장하였다. 배발생캘러스는 연한 노란색을 띠며 체세포배로 분화되었으며 이들 체세포배는 MS액체배지에서 발아되어 식물체로 성장하였다. 참나물 현탁배양세포 유래 배발생캘러스로부터 분리한 mRNA로부터 cDNA library를 합성하여 PCR을 수행한 결과 제조된 library의 삽입절편의 크기가 대부분 500bp이상임을 확인하였다. 이들 cDNA library로부터 전체 1.5 $\times$$10^{6}$개의 plaque를 혼성화하여 일차의 screening을 통해 19개의 cDNA clone을, 이차의 screening을 통해 5개의 cDNA clone을 얻었으며 이중 4개의 cDNA clone은 참나물 shoot의 HD-Zip 유전자인 Phz4 유전자와 동일한 약 1.4 kb 정도인 것으로 나타났으나, 1개의 cDNA clone, Phc5는 약 1.5kb정도의 크기를 나타내었다. 1.5kb인 Phc5는 Phz4유전자의 5'쪽으로 163bp의 염기가 추가로 발견되어 총 1,531 bp에 해당하였으며 18개의 polyA tail을 가지고 있었다. Phc5는 284번째에 ATG개시코돈이 있고 302개의 아미노산을 암호화하는 906개의 단백질 암호화 부위와 Homeodomain을 갖고 있었다. Phc5로부터 추정된 단백질은 기존 전사조절자에서 많이 보고된 HD의 구조적 특징을 갖고 있었다.

• 대한한방내과학회지
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• 제32권1호
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• pp.1-9
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• 2011

Objectives : This study was performed in order to investigate the effect of Panax notoginseng(SCG) on phenylhydrazine (PHZ)-induced hemolytic anemia in rats. Materials and Methods : Rats were divided equally into 3 groups (Normal, Control, SCG). Anemic model rats (Control, SCG) were induced by the treatment of PHZ (40mg/kg/day, i.p.) for 3 days. Red blood cell, hemoglobin, reticulocyte count, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were determined on days 0, 4, 7 and 10. Body weight was investigated on days 0, 2, 4, 6, 8, 10 and weight of spleen was measured on day 10. Results : In the SCG group, significantly higher levels of RBC was found on day 4 and higher concentration of Hb on days 4, 7 and 10. Furthermore, reticulocyte count was dramatically lower on day 10 compared to the control group. Conclusions : These results suggest that SCG may be beneficial in the treatment of hemolytic anemia.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.672-680
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• 2015

As a global regulatory gene in Streptomyces, afsR can activate the biosynthesis of many secondary metabolites. The effect of afsR on the biosynthesis of a phenazine metabolite, lomofungin, was studied in Streptomyces lomondensis S015. There was a 2.5-fold increase of lomofungin production in the afsR-overexpressing strain of S. lomondensis S015 N1 compared with the wild-type strain. Meanwhile, the transcription levels of afsR and two important genes involved in the biosynthesis of lomofungin (i.e., phzC and phzE) were significantly upregulated in S. lomondensis S015 N1. The optimization of metal chlorides was investigated to further increase the production of lomofungin in the afsR-overexpressing strain. The addition of different metal chlorides to S. lomondensis S015 N1 cultivations showed that CaCl₂, FeCl₂, and MnCl₂ led to an increase in lomofungin biosynthesis. The optimum concentrations of these metal chlorides were obtained using response surface methodology. CaCl₂ (0.04 mM), FeCl₂ (0.33 mM), and MnCl₂ (0.38 mM) gave a maximum lomofungin production titer of 318.0 ± 10.7 mg/l, which was a 4.1-fold increase compared with that of S. lomondensis S015 N1 without the addition of a metal chloride. This work demonstrates that the biosynthesis of phenazine metabolites can be induced by afsR. The results also indicate that metal chlorides addition might be a simple and useful strategy for improving the production of other phenazine metabolites in Streptomyces.