• 생명과학회지
• /
• 제18권2호
• /
• pp.148-153
• /
• 2008

Arabidopsis의 피토크롬 2중 돌연변이형 (phrAB)은 야생형 (WT)과 비교하여 뿌리의 굴중성 반응이 지연되었다. 중력 자극을 받은 지 8시간 후에 돌연변이체의 굴중성 반응은 야생형의 48%를 나타내었다 지연된 반응은 중력 자극을 준 후 1.5 시간 뒤에 나타났다. 12시간 동안 야생형과 돌연변이형의 뿌리 절편에서 에틸렌 생성을 측정하였다. 돌연변이형의 에틸렌 생성은 12시간이 경과한 후에 야생형의 40% 정도로 감소되었다. 이러한 결과는 피토크롬이 에틸렌 생성과 연관되어 있음을 제시하고 있다. 일반적으로 에틸렌은 식물의 뿌리나 줄기를 억제한다. 본 연구에서는 에틸렌 전구체인 1-aminocycloprpane-1-carboxylic acid (ACC)를 처리하여 뿌리의 생장을 측정하였다. 야생형은 ACC 존재하에 뿌리 생장이 억제되었으나, 돌연변이형은 야생형만큼 억제를 나타내지 않았다. 이 결과를 확인하기 위하여 ACC 존재하에 굴중성 반응을 측정한 결과, 야생형은 ACC가 없는 경우와 비교하여 37.4%의 억제를 나타냈으나, 돌연변이형은 ACC가 없는 경우와 비교하여 6.6%만을 억제하였다. 이 결과는 피토크롬이 에틸렌 생성을 통하여 뿌리 굴중성 반응을 조절한다는 것을 제시한다.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVII)
• /
• pp.904-909
• /
• 2005

To optimize the removal of free fatty acid in crude vegetable oil, response surface methodology was applied to determine the effects of five level-four factors and their reciprocal interactions on removal of free fatty acid. A total of 30 individual experiments were performed, which were designed to study reaction temperature, reaction time, catalyst amount and methanol amount. A statistical model predicted that the highest removal yield of free fatty acid was 99.8%, at the following optimized reaction conditions: a reaction temperature of 64.99$^{\circ}C$, a reaction time of 36.20 mins., an catalyst amount of 13.01% (w/v), and a methanol amount of 15% (v/v). Using these optimal factor values under experimental conditions in three independent replicates, the average removal yield was well within the value predicted by the model.

• Journal of Microbiology and Biotechnology
• /
• 제32권6호
• /
• pp.783-791
• /
• 2022

Gamma-aminobutyric acid (GABA) improves various physiological illnesses, including diabetes, hypertension, depression, memory lapse, and insomnia in humans. Therefore, interest in the commercial production of GABA is steadily increasing. Lactic acid bacteria (LAB) have widely been reported as a GABA producer and are safe for human consumption. In this study, GABA-producing LAB were preliminarily identified and quantified via GABase assay. The acid and bile tolerance of the L. plantarum FBT215 strain were evaluated. The one-factor-at-a-time (OFAT) strategy was applied to determine the optimal conditions for GABA production using HPLC. Response surface methodology (RSM) with Box-Behnken design was used to predict the optimum GABA production. The strain FBT215 was shown to be acid and bile tolerant. The optimization of GABA production via the OFAT strategy resulted in an average GABA concentration of 1688.65 ± 14.29 ㎍/ml, while it was 1812.16 ± 23.16 ㎍/ml when RSM was applied. In conclusion, this study provides the optimum culture conditions for GABA production by the strain FBT215 and indicates that L. plantarum FBT215 is potentially promising for commercial functional probiotics with health claims.

• The Plant Pathology Journal
• /
• 제38권5호
• /
• pp.432-448
• /
• 2022

Planthopper infestation in rice causes direct and indirect damage through feeding and viral transmission. Host microbes and small RNAs (sRNAs) play essential roles in regulating biological processes, such as metabolism, development, immunity, and stress responses in eukaryotic organisms, including plants and insects. Recently, advanced metagenomic approaches have facilitated investigations on microbial diversity and its function in insects and plants, highlighting the significance of microbiota in sustaining host life and regulating their interactions with the environment. Recent research has also suggested significant roles for sRNA-regulated genes during rice-planthopper interactions. The response and behavior of the rice plant to planthopper feeding are determined by changes in the host transcriptome, which might be regulated by sRNAs. In addition, the roles of microbial symbionts and sRNAs in the host response to viral infection are complex and involve defense-related changes in the host transcriptomic profile. This review reviews the structure and potential functions of microbes and sRNAs in rice and the associated planthopper species. In addition, the involvement of the microbiota and sRNAs in the rice-planthopper-virus interactions during planthopper infestation and viral infection are discussed.

• Journal of Microbiology and Biotechnology
• /
• 제16권1호
• /
• pp.126-135
• /
• 2006

In a previous study, a biological response modifier (BRM) specifically enhancing the function of B-cells was isolated from Korean fermented soybean paste (Kfsp), but not from non-fermented soybeans. In this study, we attempted to isolate the bacteria producing the BRM from Kfsp (KfspBRM) by ELISA using anti-KfspBRM and by B-cell proliferation. Five bacteria whose culture supernatants showed the BRM activities were isolated, and one of them was identified as Bacillus licheniformis E1. The bacterial BRM (bBRM) originated from a slime layer of B. licheniformis El had a molecular weight of 1,594 kDa, and contained $33\%\;(w/w)$ of reduced sugar and $4.6\%\;(w/w)$ of protein content. The bBRM appeared to be a glycoprotein that is physically, structurally, and functionally similar to the KfspBRM, suggesting that the isolates including B. licheniformis El may produce the KfspBRM in the fermentation process of soybean paste. The mass production of the BRM by the bacterium may help to study B-cells in immunology, and the enrichment of the BRM in Kfsp may help patients in future who are medically in need of potentiation of B-cell proliferation and antibody production.

• KSBB Journal
• /
• 제17권3호
• /
• pp.213-227
• /
• 2002

To date, the majority of biosensor technologies use binding components such as enzymes antibodies, nucleic acids and protein ligands. In contrast, the goal underlying the use of cells and tissues of animals and plants for a sensor system is to obtain systems capable of extracting information based on the biological activity, mechanisms of action and consequences of exposure to a chemical or biological agent of interest. These systems enable the interrogation of more complex biological response and offer the potential to gather higher information content from measuring physiologic and metabolic response. In these articles, same of the recent trends and applications of microbial biosensors in environmental monitoring and for use in food and fermentations have been reviewed. This endeavor presents many technological challenges to fabricate new microbial biosensors for other scientific field.

• 한국전자통신학회논문지
• /
• 제9권4호
• /
• pp.499-508
• /
• 2014

본 논문에서는 생체신호인 PPG, GSR 신호의 변화에 따라 구동되는 LED 감성조명 시스템을 구현하였다. 개발된 GSR 및 PPG 센서모듈로부터 인체의 생체신호를 측정하고, 측정된 생체신호를 이용하여 MCU에서 제안된 각성 이완 판별맵에 근거하여 피검자의 각성 또는 이완 상태를 판단한다. 피검자의 상태에 대응하는 LED 조명색상의 변화를 주어, 피검자가 안정 상태의 감정에 도달할 수 있도록 하는 감성조명 시스템을 개발하였다.

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2003년도 생물공학의 동향(XIII)
• /
• pp.351-355
• /
• 2003

Screening 실험을 통하여 결정된 주요인자인 sucrose, nitrogen, 배양온도로 인자의 최적수준을 결정하는 표면반응법중 하나인 Box-Behnken design을 수행하였다. 각 인자의 상관관계를 통하여 sucrose는 90 g/L, nitrogen은 41 mM, 온도는 $22^{\circ}C$가 최적수준으로 결정이 되었으며 확인실험을 통하여 대조구보다 세포생장이 증가하였을 뿐만 아니라 hGM-CSF의 생산도 약 2배 정도 증가되었음을 확인하였다. 이것은 고농도의 sucrose로 인해 배지내로의 hGM-CSF의 분비가 촉진되었기 때문이며 또한 저온으로 인해 분비된 hGM-CSF를 분해하는 protease 활성이 감소되었기 때문인 것으로 사료된다.

• BMB Reports
• /
• 제53권2호
• /
• pp.88-93
• /
• 2020

Cisplatin is a widely used anti-cancer agent. However, the effectiveness of cisplatin has been limited by the commonly developed drug resistance. This study aimed to investigate the potential effects of endoplasmic reticulum (ER) stress to overcome drug resistance using the cisplatin-resistant A2780/CisR ovarian cancer cell model. The synthetic chalcone derivative (E)-3-(3,5-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (named DPP23) is an ER stress inducer. We found that DPP23 triggered apoptosis in both parental cisplatin-sensitive A2780 and cisplatin-resistant A2780/CisR ovarian cancer cells due to activation of reactive oxygen species (ROS)-mediated unfolded protein response (UPR) pathway in the endoplasmic reticulum. This result suggests that ROS-mediated UPR activation is potential in overcoming drug resistance. DPP23 can be used as a target pharmacophore for the development of novel chemotherapeutic agents capable of overcoming drug resistance in cancer cells, particularly ovarian cancer cells.

• 생태와환경
• /
• 제45권4호
• /
• pp.420-443
• /
• 2012

An Individual-Based Model (IBM) was developed by employing natural and toxic survival rates of individuals to elucidate the community responses of benthic macroin-vertebrates to anthropogenic disturbance in the streams. Experimental models (dose-response and relative sensitivity) and mathematical models (power law and negative exponential distribution) were applied to determinate the individual survival rates due to acute toxicity in stressful conditions. A power law was additionally used to present the natural survival rate. Life events, covering movement, exposure to contaminants, death and reproduction, were simulated in the IBM at the individual level in small (1 m) and short (1 week) scales to produce species abundance distributions (SADs) at the community level in large (5 km) and long (1~2 years) scales. Consequently, the SADs, such as geometric series, log-series, and log-normal distribution, were accordingly observed at severely (Biological Monitoring Working Party (BMWP<10), intermediately (BMWP<40) and weakly (BMWP${\geq}50$) polluted sites. The results from a power law and negative exponential distribution were suitably fitted to the field data across the different levels of pollution, according to the Kolmogorov-Smirnov test. The IBMs incorporating natural and toxic survival rates in individuals were useful for presenting community responses to disturbances and could be utilized as an integrative tool to elucidate community establishment processes in benthic macroin-vertebrates in the streams.