• Journal of Korean Society of Forest Science
• /
• v.102 no.3
• /
• pp.331-337
• /
• 2013

Formate dehydrogenase (FDH), catalyzing the oxidation of the formate ion to carbon dioxide, is known as the stress protein in response to drought, low temperature and pathogen infection. To study the functions of FDH in poplar (Populus alba ${\times}$ P. glandulosa), we isolated a FDH cDNA (PagFDH1) and examined its expressional characteristics. The PagFDH1 is 1,499 base pairs long and encodes a putative 388 amino acid protein with an expected molecular mass of 42.5 kDa. The PagFDH1 protein has N-terminal mitochondria signal peptide and $NAD^+$ binding domain. Southern blot analysis indicated that a single copy of the PagFDH1 is present in the poplar genome. PagFDH1 is expressed highly in the suspension cells (especially in the lag and early exponential phases) and moderately in roots, flowers and leaves. ABA-mediated enhanced expression of PagFDH1 in response to drought and salt stress treatments indicates that the gene product could play an important role in the development of stress resistant trees.

• Journal of the Korean Wood Science and Technology
• /
• v.50 no.3
• /
• pp.159-166
• /
• 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.

• KSBB Journal
• /
• v.26 no.3
• /
• pp.189-192
• /
• 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.

• Nutrition Research and Practice
• /
• v.2 no.4
• /
• pp.195-199
• /
• 2008

Alcoholism has been associated with folate deficiency in humans and laboratory animals. Previous study showed that ethanol feeding reduces the dehydrogenase and hydrolase activity of 10-formyltetrahydrofolate dehydrogenase (FDH) in rat liver. Hepatic ethanol metabolism generates acetaldehyde and acetate. The mechanisms by which ethanol and its metabolites produce toxicity within the liver cells are unknown. We purified FDH from rat liver and investigated the effect of ethanol, acetaldehyde and acetate on the enzyme in vitro. Hepatic FDH activity was not reduced by ethanol or acetate directly. However, acetaldehyde was observed to reduce the dehydrogenase activity of FDH in a dose- and time-dependent manner with an apparent $IC_{50}$ of 4 mM, while the hydrolase activity of FDH was not affected by acetaldehyde in vitro. These results suggest that the inhibition of hepatic FDH dehydrogenase activity induced by acetadehyde may play a role in ethanol toxicity.

• Journal of Korea Port Economic Association
• /
• v.18 no.1
• /
• pp.3-26
• /
• 2002

The purpose of this paper is to Investigate the productive efficiency and competitive strength of world container ports using the DEA, Super-efficiency, and FDH methods with the raw data from previous research by Jun et al.(1993). The super-efficiency measure examines the maximal radial change In input, outputs for an observation to remain efficient. Therefore, it provides a means of distinguishing between efficient observations, which would otherwise seem identical. FDH provides a good test mechanism for examining the practical implications of the choice available among alternative efficiency measures and orientations, because of the lack of convexity of its production possibility set. Both methods are complementary to DEA. This paper follows the traditional productivity analysis method overcoming the limitation of previous studies by using the DEA, FDH and Super-efficiency methods, and proposing in measure the relative competitive strength of worldwide container ports. The main empirical results of this paper are as follows: Firstly the ports of Singapore, Hongkong, Kilrung, Busan, Tokyo. and Longbeach were found to be efficient In the CCR model. The ports of Felixstowe, Bangkok, Singapore, Hongkong, Kilung, Busan, Tokyo, and Longbeach were found to be efficient in the BCC model. Secondly, super. efficiency rankings under CRS and input-oriented model are as follows: Longbeach, Keelung, Singapore, Busan, Tokyo, and Honkong. However, it was difficult In differenciate the rankings under the VRS and input-oriented model. due to major difficulties posed by the ports of Singapore, Hongkong, and Longbeach. Thirdly, the FDH method shows that the inefficient ports are Bremerhaven, Antwerp, Le Havre, Kobe, Seattle, New York The policy Implications of this study are as follows: Firstly, when port authorities want to measure the international competitive strength of container ports and enhance their productive efficiency, they should consider the traditional method as well as introducing the Super-efficiency and FDH methods. Secondly, according to the analysis results of the super-efficiency and FDH methods, poll authorities should recommend benchmarks ports and dominated ports as reference ports in order to enhance the productive efficiency of their container ports that have an efficiency rating of less than 1. Efficient ports whose efficiency ratings are over 1 in the Input-oriented Super-efficiency model should also consider the usage of input and output elements used by more efficient ports.

• BMB Reports
• /
• v.40 no.4
• /
• pp.604-609
• /
• 2007

An Asp/His catalytic site of 10-formyltetrahydrofolate dehydrogenase (FDH) was suggested to have a similar catalytic topology with the Asp/His catalytic site of serine proteases. Many studies supported the hypothesis that serine protease inhibitors can bind and modulate the activity of serine proteases by binding to the catalytic site of serine proteases. To explore the possibility that soybean trypsin inhibitor (SBTI) can recognize catalytic sites of FDH and can make a stable complex, we carried out an SBTI-affinity column by using rat liver homogenate. Surprisingly, the Rat FDH molecule with two typical liver proteins, carbamoyl-phosphate synthetase 1 (CPS1) and betaine homocysteine S-methyltransferase (BHMT) were co-purified to homogeneity on SBTI-coupled Sepharose and Sephacryl S-200 followed by Superdex 200 FPLC columns. These three liver-specific proteins make a protein complex with 300 kDa molecular mass on the gel-filtration column chromatography in vitro. Immuno-precipitation experiments by using anti-FDH and anti-SBTI antibodies also supported the fact that FDH binds to SBTI in vitro and in vivo. These results demonstrate that the catalytic site of rat FDH has a similar structure with those of serine proteases. Also, the SBTI-affinity column will be useful for the purification of rat liver proteins such as FDH, CPS1 and BHMT.

• Proceeding of EDISON Challenge
• /
• 2013.04a
• /
• pp.67-75
• /
• 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.

• Journal of Nutrition and Health
• /
• v.42 no.5
• /
• pp.423-433
• /
• 2009

Folate and vitamin $B_{12}$ are essential cofactors for homocysteine (Hcy) metabolism. Homocysteinemia has been related with cardiovascular and neurodegenerative disease. We examined the effect of folate and/or vitamin $B_{12}$ deficiency on biomarkers of one carbon metabolism in blood, liver and brain, and analyzed the correlation between vitamin biomarkers in mild and moderate homocysteinemia. In this study, Sprague-Dawley male rats (5 groups, n = 10) were fed folatesufficient diet (FS), folate-deficient diet (FD) with 0 or 3 g homocystine (FSH and FDH), and folate-/vitamin $B_{12}$-deficient diet with 3 g homocystine (FDHCD) for 8 weeks. The FDH diet induced mild homocysteinemia (plasma Hcy 17.41 ${\pm}$ 1.94 nmol/mL) and the FDHCD diet induced moderate homocysteinemia (plasma Hcy 44.13 ${\pm}$ 2.65 nmol/mL), respectively. Although liver and brain folate levels were significantly lower compared with those values of rats fed FS or FSH (p < 0.001, p < 0.01 respectively), there were no significant differences in folate levels in liver and brain among the rats fed FD, FDH and FDHCD diet. However, rats fed FDHCD showed higher plasma folate levels (126.5 ${\pm}$ 9.6 nmol/L) compared with rats fed FD and FDH (21.1 ${\pm}$ 1.4 nmol/L, 22.0 ${\pm}$ 2.2 nmol/L)(p < 0.001), which is the feature of "ethyl-folate trap"by vitamin $B_{12}$ deficiency. Plasma Hcy was correlated with hepatic folate (r = -0.641, p < 0.01) but not with plasma folate or brain folate in this experimental condition. However, as we eliminated FDHCD group during correlation test, plasma Hcy was correlated with plasma folate (r = -0.581, p < 0.01), hepatic folate (r = -0.684, p < 0.01) and brain folate (r = -0.321, p < 0.05). Hepatic S-adenosylmethionine (SAM) level was lower in rats fed FD, FDH and FDHCD than in rats fed FS and FSH (p < 0.001, p < 0.001 respectively) and hepatic S-adenosylhomocysteine (SAH) level was significantly higher in those groups. The SAH level in brain was also significantly increased in rats fed FDHCD (p < 0.05). However, brain SAM level was not affected by folate and/or vitamin $B_{12}$ deficiency. This result suggests that dietary folate- and vitamin B12-deficiency may inhibit methylation in brain by increasing SAH rather than decreasing SAM level, which may be closely associated with impaired cognitive function in nutritional homocysteinemia.

• Corrosion Science and Technology
• /
• v.17 no.6
• /
• pp.287-291
• /
• 2018

In this study, corrosion behavior of a SA178-A alloy used in the boiler tube of a district heating system was investigated in different environments where it was exposed to pure water, district heating (DH) water, and filtered district heating (FDH) water. After the corrosion test, the surface morphology was examined for observation of the number of pitting sites and pitting area fraction, using a scanning electron microscope. The DH water and FDH water conditions resulted in a lower corrosion potential and pitting potential, and revealed a significantly higher corrosion rate than the pure water condition. The pitting sites in the DH water (pH 9.6) were approximately eighteen times larger than those in the pure water (pH 9.6). Compared to the DH water, the corrosion potential became more noble in the FDH water condition, where iron ions were reduced through filtration. However, the corrosion rate increased in the FDH water due to an increased concentration of chloride ions, which deteriorated the stability of passive film.

• Applied Chemistry for Engineering
• /
• v.20 no.4
• /
• pp.449-452
• /
• 2009

The absence of Fe, Se, and Mo in a minimal medium prevented the production of hydrogen from the anaerobic culture of Escherichia coli MC4100. Fe, Se, and Mo are known to be cofactors of formate dehydrogenase ($FDH_{II}$) of both E. coli and Enterobacter aerogenes. Hence when these trace elements are absent in the minimal medium, hydrogen production through formate dehydrogenation would be inhibited not only in E. coli but also in E. aerogenes. Hydrogen production by E. aerogenes 413 was delayed when lacking these trace elements. Therefore, it is believed that hydrogen production of E. aerogenes is initiated not by the reoxidation of nicotinamide adenine dinucleotide (NADH) but by formate decarboxylation.