• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.531-534
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• 2000

The fumB gene encoding anaerobic fumarase of Escherichia coli XL1-Blue was introduced to solve the malic acid accumulation problem. When NZN111 harboring pTrcMLFu was cultured, 7 g/L of succinic acid was produced and malic acid was not accumulated.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.213.2-213
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• 1999

No Abstract, See Full Text

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.136-138
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• 2002

In this work we describe the on-line monitoring technique for the analysis of fumaric acid in biotechnological processes. Fumarase and malate dehydrogenase(MDH) were immobilized on epoxy carrier and integrated into a FIA system. The effects of carrier buffer flow rate, pH, reaction temperature on the immobilized fumarase/MDH were investigated for the development of a fumarate-FIA system. Furthermore the effects of substrates, salts and metabolites dissolved in the sample on the activity of the immobilized enzyme were investigated.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권4호
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• pp.252-255
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• 2004

A pfl ldhA double mutant Escherichia coli strain NZN 111 was used to produce succinic acid by overexpressing the E. coli malic enzyme gene (sfcA). This strain, however, produced a large amount of malic acid as well as succinic acid. After the analyses of the metabolic pathways, the fumB gene encoding the anaerobic fumarase of E. coli was co-amplified to solve the problem of malic acid accumulation. A plasmid, pTrcMLFu, was constructed, which contains an artificial operon (sfcA-fumB) under the control of the inducible trc promoter. From the batch culture of recombinant E. coli NZN 111 harboring pTrcMLFu, 7 g/L of succinic acid was produced from 20 g/L of glucose, with no accumulation of malic acid. From the metabolic flux analysis the strain was found under reducing power limiting conditions by severe reorientation of metabolic fluxes.

• 화훼연구
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• 제18권2호
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• pp.93-97
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• 2010

본 연구는 기내에서 재생된 오리엔탈나리 'Casa Blanca'와 'Siberia' 소인경의 새로운 휴면 타파방법을 모색하고자 생장조절물질을 첨가한 온탕처리 조건을 검토하였다. 오리엔탈나리 'Casa Blanca'와 'Siberia' 두 품종 모두 $30^{\circ}C$ 증류수, 120분 온탕처리에서 맹아소요일수는 단축되었으나 맹아율이 낮았다. $GA_{4+7}$ $100mg{\cdot}L^{-1}$용액을$35^{\circ}C$ 에서 1시간 온탕 처리에 의해서 'Casa Blanca'와 'Siberia'의 맹아율은 각각 76.7%으로 크게 촉진되었고 정식 2년차의 생장과 구근 비대가 촉진되었으며, 휴면에 따른 호흡정도를 반영하는 미토콘드리아 단백질 함량과 fumarase 활성도 높아 휴면타파의 생리적 원인도 구명하였다. 생장조절물질($GA_{4+7}$)을 첨가한 온탕처리에 의해 기내에서 재생된 오리엔탈나리 소인경의 휴면을 효과적으로 타파할 수 있었다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.11-11
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• 1999

;It has been reported that suspension-cultured rice cells grown on mixed carbon sources of glucose (GIc) and acetate exhibited diauxic growth in which acetate was the preferred carbon source (Lee and Lee, 1996). Carrot (Daucus carota L.) suspension cells, showing a diauxic growth very similar to that of rice cells, were used to delineate the mechanisms underlying this preferential use of acetate over GIc. Uptakes of both GIc and 3-0-methylglucose (3-0MG), a non-metabolizable GIc analogue, were similarly inhibited when acetate or butylate, weak acids which are capable of transporting protons into the cytosol, were present in the uptake assay mixture containing cells harvested during the GIc-utilizing second growth phase. Inhibition of GIc uptake by these weak acids was similar when equivalent experiments were carried out with isolated plasma membranes. It was further shown that Glc uptake, which requires a proper proton gradient across the plasma membranes, was inhibited during the first growth phase by acetate-mediated alkalization of growth medium and/or simultaneous acidification of cytosol. This study strongly suggests that Glc utilization in plant cells is inhibited by co-presenting carbon source(s) which can alter the proton gradient across the plasma membrane. We further examined diauxic growth in culture containing GIc and malate. Unlike the case in the culture with GIc and acetate, carrot cells used GIc first. Malate was utilized only after Glc is depleted from medium. These results indicate that GIc can be a preferred or less-preferred carbon source depending on the competing carbon source. It was noted that malate was not directly taken up by cells. Instead it was converted extracellularly into fumarate which was subsequently transported into cells. During the malate-growth phase malate uptake was negligible, and fumarate uptake was active and pH-sensitive. It was shown that fumarase released into medium was responsible for the extracellular conversion of malate into fumarate. An immunoblot experiments showed that fumarase antibody raised against Arabidopsis fumarase provided positive signals only in medium in malate culture, not in fumarate or GIc cultures. This study demonstrates the first example in that fumarase, a mitochondria marker enzyme, can be present in places other than mitochondria.ndria.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.614-614
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• 2005

• Journal of Ginseng Research
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• 제41권4호
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• pp.556-565
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• 2017

Background: Recent studies have revealed that the properties Traditional Chinese Medicine is mostly associated with are substance and energy metabolism. Our study aimed to compare the effect of red ginseng (RG) (warm property) and ginseng leaves (GL; cold property) on the substance and energy metabolism of rats with hypothyroidism. Materials and methods: Rats were administered propylthiouracil intraperitoneally for 20 d to cause hypothyroidism. The reference group was orally administered Aconiti Lateralis Radix Praeparaia [FZ (Fuzi in Chinese)], while both the RG and GL groups were orally administrated crude drugs. The rectal, tail, toe, and axilla temperature of the rats were assayed every 3 d. Oxygen consumption, carbon dioxide production, heat production, and energy expenditure were measured via TSE phenoMaster/LabMaster animal monitoring system. Adenosine monophosphate-activated protein kinase, $Na^+-K^+$-ATPase, fumarase, pyruvic acid and cyclic adenosine monophosphate/cyclic guanosine monophosphate were determined. Results: The lower levels of triiodothyronine, tetraiodothyronine, and thyrotropin-releasing hormone and the higher level of thyroid stimulating hormone revealed the successful establishment of a hypothyroidism model. Oxygen consumption, carbon dioxide production, heat production, and energy expenditure in the FZ and RG groups were obviously increased. The activity of $Na^+-K^+$-ATPase and fumarase in the FZ and RG groups was significantly increased. The cyclic adenosine monophosphate/cyclic guanosine monophosphate level in the FZ and RG groups was increased, while the GL group showed the opposite. Conclusion: Our research provides a new way to explore the efficiency of Chinese medicine on the basis of the relationship between drug property and effects on substance and energy metabolism.

• Journal of Plant Biology
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• 제16권1_2호
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• pp.6-11
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• 1973

The utilization of acetate by Dunaliella tertiolecta was examined, and the detections and assays of the enzymes of the tricarboxylic acid cycle and the glyoxylate pathway were described. Acetate could not be utilized as a sole carbon source for the growth. The carboxyl carbon of acetate was incorporated more rapidly into CO2 than the methyl carbon. It was identified that malate, succinate, citrate and etc., were accumulated whne [U-14C] acetate was supplied to the cell free homogenate. The following enzyme activities were measured; acetothiokinase, isocitrate dehydrogenase, fumarase, malate dehydrogenase and aconitase. Though isocitratase, malate synthetase, succinate dehydrogenase and oxoglutarate dehydrogenase could not be detected, 14C from succinate was easily contributed to CO2 and cell component. The evidence suggested that the glyoxylate pathway was not operative and showed that the TCA cycle was the all important pathway in the oxidation of acetate to CO2 in Dunaliella.

• KSBB Journal
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• 제18권5호
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• pp.377-384
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• 2003

본 연구에서는 푸마르산 또는 숙신산을 생산/소비하는 생물공정에서 각 물질의 농도를 온라인 모니터링을 하기 위한 흐름주입분석기술 (FIA)을 개발하였다. 각 효소반응에 필요한 효소 (Fum/MDH, ICL/ICDH)를 VA-Epoxy Biosynth E3-carrier에 공유 결합에 의해 고정화하였고 소형 고정화 효소반응기를 흐름주입분석 장치에 도입하였다. 푸마르산-FIA 및 숙신산-FIA 시스템에서 고정화 효소 반응기의 특성 (예를 들면, 고정화 Fum/MDH 효소 반응기와 ICL/ICDH 효소 반응기는 최적 pH가 9.0이었으며 35$^{\circ}C$의 반응온도에서 최대 활성을 보임) 을 연구하였고 실제 생물공정에의 적용 가능성을 조사하기 위해 각 FIA 시스템의 성능을 조사하였다. 또한 모사공정과 실제 발효공정에서 푸마르산과 숙신산의 농도를 온라인 모니터링하여 오프라인 분석값과 비교하였고 잘 일치함을 볼 수 있었다.