• KSBB Journal
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• 제26권3호
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• pp.189-192
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• 2011

Much interest has been recently focused on the production of large quantities of hydrogen, due to its potential importance in our economy and needs in the petroleum and chemical industries. Formate dehydrogenase H (FDH-H) from Escherichia coli containing selenocysteine that oxidizes formate to carbon dioxide with the release of hydrogen is a component of the anaerobic formate hydrogen-lyase complex of E. coli. To make full use of FDH-H, we need effective expression condition. In this approach, we investigated the effect of pH on FDH-H stability and observed the effect of selenite and formate concentration on the activity of FDH-H. Additionally, coexpression of selenocysteine insertion genes were tried to improve the expression of FDH-H. The highest level of FDH-H expression was achieved by coexpression of selenocysteine insertion genes (pSUABC) as well as by the addition of $10\;{\mu}M$ selenite and 10 mM formate. At this optimized condition, a 2.6 fold elevation of expression of FDH-H was achieved.

• 한국미생물·생명공학회지
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• 제25권4호
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• pp.403-407
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• 1997

Medium components for maximum activity of NAD$^{+}$-dependent formate dehydrogenase (EC 1.2.1.2; FDH) were optimized with a methanol-assimilating yeast Hansenula sp. MS-364, preserved by our laboratory. The maximum activity of the enzyme was obtained when the strain was cultivated at 30$circ$C for 24 hours in a medium containing methanol 3%(v/v), yeast extract 0.8%(w/v), K$_{2}$HPO$_{4}$, 0.1%(w/v), KH$_{2}$PO$_{4}$ 0.1%(W/V), MgSO$_{4}$, 7H$_{2}$O 0.05%(w/v), and the pH of the culture broth was adjusted at 5.0.

• 공업화학
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• 제20권4호
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• pp.449-452
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• 2009

철,셀레늄,그리고 몰리브데늄이 결여되어 있는 최소배지는 Escherichia coli MC4100의 혐기성 배양에서의 수소생산을 억제하였다. 철, 셀레늄, 그리고 몰리브데늄은 대장균과 Enterobacter 모두의 formate dehydrogenase ($FDH_{II}$) 효소의 보조인자로 알려져 있다.그러므로 이러한 미량성분들이 최소배지에 결여되어 있을 때는 $FDH_{II}$를 통한 수소생산이 대장균 뿐만 아니라 E. aerogenes에서도 저해될 것이다. 이러한 성분들이 부족할 때 E. aerogenes 413에 의한 수소 생산은 지연되었다.그러므로,E. aerogenes에 의한 수소 생산은 NADH의 재산화가 아닌 포메이트 탈카복시 반응에 의해서 시작된다고 사료된다.

• EDISON SW 활용 경진대회 논문집
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• 제2회(2013년)
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• pp.67-75
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• 2013

최근 이상기후의 원인으로 손꼽히는 물질의 중심에는 이산화탄소가 있으며 이를 제거하기 위한 여러 연구가 진행되고 있다. 최근에는 전극이 있는 수조에 미생물을 넣고 이산화탄소를 화학적 에너지로 사용할 수 있도록 알코올로 변환시켜주는 시스템이 발표되었다. 이에 따라 본 연구진에서는 이러한 전극 시스템에서 이용될 수 있는 효소를 찾고 효소촉매화 반응의 메커니즘을 자세히 연구하고자 하였다. 본 연구에서 사용된 효소인 Formate dehydrogenase (FDH)는 formate를 조효소인 nicotinamide adenine dinucleotide ($NAD^+$)를 사용하여 이산화탄소로 산화시키는 반응을 촉진시키는 효소이다. 본 연구에서는 이러한 FDH의 산화반응의 역반응을 이용하여 이산화탄소를 효과적으로 분해하는 메커니즘을 연구하기에 앞서 wild type의 반응 메커니즘에 대해 깊이 연구하고자 B3LYP 방법의 양자계산을 하여 반응의 transition state와 potential energy를 조사하였다.

• 한국미생물·생명공학회지
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• 제34권3호
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• pp.216-220
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• 2006

본 균의 생육 및 효소생산에 유용한 탄소원으로서 자연계의 식물에 풍부한 펙틴을 탄소원으로 할 경우, 그 생육도는 전분보다 뛰어났으며, alcohol oxidase와 catalase의 생산량도 높아지는 것으로 나타났다. 특히 alcohol oxidase의 경우는 전분의 15배 이상의 생산량을 보여 본 균과 펙틴 이용성과의 관계를 시사하였고, 세포외 pectin esterase, pectinase등의 높은 활성이 검출되어 이를 증명하였다. 또한 alcohol oxidase 반응에서 생성되는 물질인 formaldehyde를 산화하는 formaldehyde dehydrogenase와, formate를 산화하여 $CO_2$를 생성하는 formate dehydrogenase의 반응을 발견하여, 본 균의 pectin 이용성과 관련한 일련의 에너지 대사계의 존재를 추정할 수 있었다.

• Korean Chemical Engineering Research
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• 제54권5호
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• pp.719-721
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• 2016

Formate has been considered as an environmentally sustainable feedstock that can be used to accelerate the production of valuable chemicals. This study presents brief results of the formatotrophic production of Poly-${\beta}$-hydroxybutyric acid (PHB) by Methylobacterium sp. To evaluate the production of PHB, five species of Methylobacteria were tested using formate as the sole carbon and energy source. Methylobacterium chloromethanicum CM4 exhibited the highest productivity of PHB, which showed 1.72 g/L PHB production, 32.4% PHB content, and 0.027 g-PHB/g-formate PHB yield. These results could be used for the formatotrophic production of PHB with the concurrent reduction of $CO_2$ to formate.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.588-588
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• 2005

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.211-214
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• 2007

A solid-phase microextraction and gas chromatography-mass spectrometry utilizing $^{13}C$-formate as an internal standard for the determination of formate was proved to be applicable as a reliable quantitative method in several plants. We were the first to discover that trees contain larger pool sizes of formate than herbs. Our data also showed that the formate level of the leaves increased after the methanol-spraying, suggesting that methanol oxidation could convert formaldehyde into formate. In addition, drought and chilling led to the increase of endogenous formate in Arabidospsis thaliana. These results confirmed that formate is a universal stress signal in plants.

• Journal of the Korean Wood Science and Technology
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• 제50권3호
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• pp.159-166
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• 2022

CO₂ emissions are the primary reason for global warming; hence, biological and chemical technologies for converting CO₂ into useful compounds are being actively studied. Biological methods using enzymes can convert CO₂ under mild conditions. Formate dehydrogenase (FDH) is a representative CO₂ conversion enzyme. Its function was revealed after isolation from bacteria, yeast, and plants. In this study, we evaluated the CO₂ conversion potential of FDH isolated from wood-rotting fungi. After isolating the FDH gene (TvFDH) from Trametes versicolor, we cloned the full-length FDH from T. versicolor and expressed it in a cell-free expression system. The gene encoding TvFDH was identified as 1,200 bp open reading frame (ORF) and the expected molecular weight of the protein was approximately 42 kDa. Overexpression of the recombinant crude protein including TvFDH was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Enzyme activities and metabolite analyses confirmed the efficiency of TvFDH for CO₂ reduction.

• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.501-508
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• 2003

Artificial coupling of one enzyme with another can provide an efficient means for the production of industrially important chemicals. Xylose reductase has been recently discovered to be useful in the reductive production of xylitol. However, a limitation of its in vitro or in vivo use is the regeneration of the cofactor NAD(P)H in the enzyme activity. In the present study, an efficient process for the production of xylitol from D-xylose was established by coupling two enzymes. A NADH-dependent xylose reductase (XR) from Pichia stipitis catalyzed the reduction of xylose with a stoichiometric consumption of NADH, and the resulting cofactor $NAD^+$ was continuously re-reduced by formate dehydrogenase (FDH) for regeneration. Using simple kinetic analyses as tools for process optimization, suitable conditions for the performance and yield of the coupled reaction were established. The optimal reaction temperature and pH were determined to be about $30^{\circ}C$ and 7.0, respectively. Formate, as a substrate of FDH, affected the yield and cofactor regeneration, and was, therefore, adjusted to a concentration of 20 mM. When the total activity of FDH was about 1.8-fold higher than that of XR, the performance was better than that by any other activity ratios. As expected, there were no distinct differences in the conversion yields of reactions, when supplied with the oxidized form $NAD^+$ instead of the reduced form NADH, as a starting cofactor for regeneration. Under these conditions, a complete conversion (>99%) could be readily obtained from a small-scale batch reaction.