• Journal of Nutrition and Health
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• v.24 no.4
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• pp.350-355
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• 1991

The effect of thyroid hormone on hepatic levels of 10-formyltetrahydrofolate dehydrogenase (10-formyltetrahydrofolate : NADP oxidoreductase, E.C. 1.5.1.6.) was studied using Sprague-Dawley rat. Hypothyroidism increased histidine oxidation by 5 fold and increased 10-formyltetrahydrofolate dehydrogenase activity by 142%, and also decreased methylenetetrahydrofolate reductase activity by 52%. Decreased methylenetetrahydrofolate reductase acts by decreasing synthesis of 5-methyl folate, thereby increasing the proportion of non-methyl folate required for folate-dependent reactions. Increased histidine oxidation produced by hypothyroidism may be attributed to its effect in decreasing 10-formyltetrahydrofolate dehydrogenase.

• Journal of Life Science
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• v.27 no.12
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• pp.1403-1409
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• 2017

In this study, the xylitol dehydrogenase (XYL2) gene was expressed in Saccharomyces cerevisiae as a host cell for ease of use in the degradation of lignocellulosic biomass (xylose). To select suitable expression systems for the S.XYL2 gene from S. cerevisiae and the P.XYL2 gene from Pichia stipitis, $pGMF{\alpha}-S.XYL2$, $pGMF{\alpha}-P.XYL2$, $pAMF{\alpha}-S.XYL2$ and $pAMF{\alpha}-P.XYL2$ plasmids with the GAL10 promoter and ADH1 promoter, respectively, were constructed. The mating factor ${\alpha}$ ($MF{\alpha}$) signal sequence was also connected to each promoter to allow secretion. Each plasmid was transformed into S. cerevisiae $SEY2102{\Delta}trp1$ strain and the xylitol dehydrogenase activity was investigated. The GAL10 promoter proved more suitable than the ADH1 promoter for expression of the XYL2 gene, and the xylitol dehydrogenase activity from P. stipitis was twice that from S. cerevisiae. The xylitol dehydrogenase showed $NAD^+$-dependent activity and about 77% of the recombinant xylitol dehydrogenase was secreted into the periplasmic space of the $SEY2102{\Delta}trp1/pGMF{\alpha}-P.XYL2$ strain. The xylitol dehydrogenase activity was increased by up to 41% when a glucose/xylose mixture was supplied as a carbon source, rather than glucose alone. The expression system and culture conditions optimized in this study resulted in large amounts of xylitol dehydrogenase using S. cerevisiae as the host strain, indicating the potential of this expression system for use in bioethanol production and industrial applications.

• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.461-467
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• 1989

The activity of lactate dehydrogenase in plasma and various tissues(skeletal muscle, cardiac muscle, liver, lung, kidney and spleen) of Korean native cattle in a Chonju abattoir, the Breeding Stock Farm and Animal Farm of Chonbuk University was determined by using ultra violet method. Using polyacrylamide gel electrophoresis, the lactate dehydrogenase isoenzyme distrimution of plasma and various tissues in Korean native cattle was studied. The plasma lactate dehydrogenase activity of Korean native cattle was $554.80{\pm}92.70IU/l$ and the lactate dehydrogenase activity of male plasma was $543.96{\pm}97.89IU/l$, which was lower than that of female plasma, $579.19{\pm}78.09IU/l$. The plasma lactate dehydrogenase activity of calf was $557.31{\pm}110.27IU/l$ and was no significantly different from that of adult Korean native cattle. But the range of calf lactate dehydrogenase activity was larger than that of adult Korean native cattle. In tissues, the lactate dehydrogenase activity was decreased in order of lung, kidney, spleen, liver, heart and skeletal muscle. The lung had the greatest activity and the skeletal muscle had the least. Lactate dehydrogenase isoenzymes in plasma and tissues were found to have a characteristic distribution and quantitative isoenzyme patterns. In plasma, the LDH1 usually had the greatest activity and other isoenzymes showed a decreasing tendency in order of LDH2, LDH3, LDH4 and LDH5. The distribution of lactate dehydrogenase isoenzymes had a wide variation in tissues. But the distribution of LDH isoenzymes in plasma was similar to that in kidney, and also cardiac muscle and spleen had similar pattern in LDH isoenzymes distribution.

• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.425-431
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• 1989

This study was undertaken to investigate the changes of enzyme activities resulted from low concentrated carbon monoxide poisoning on the caudate nucleus in rat. The activities of cytochrome oxidase, succinate dehydrogenase and lactate dehydragenase were observed histochemically, after the experimental animals were poisoned to 100ppm carbon monoxide for 8 hours every day from one day to 16 days. The materials were sliced from coronal section at the level of the optic chiasm and immediately frozen sections of $10{\mu}m$ thickness were cut on the cryostat at $-15^{\circ}C$ and incubated in the medium containing substrate for histochemical detection of cytochrome oxidase, succinate dehydrogenase and lactate dehydrogenase. The sections were mounted in glycerol gelatin and observed under light microscope. It was obtained that cytochrome oxidase activity decreased moderately and succinate dehydrogenase activity showed marked or moderate activity during entire poisoning period and lactate dehydrogenase activity showed marked or moderate activity from one to 8 days but recovered to normal condition at 16th day.

• The Korean Journal of Ecology
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• v.14 no.1
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• pp.75-85
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• 1991

Changes in the activities of isocitrate dehydrogenase (IDH) and glutamate dehydrogenase (GDH) and changes in free amino acids in the cytoplasm of Saccharomyces cerevisiae have been studied under heat shock condition. Heat shock conditions led to a significant decrease of NAD-IDH and NAD-GDH, It was shown appeared that the meaningful patterns of increase of NADP-IDH and NADP-GDH. It suggested that heat shock in yeast leads to a splitting of the TCA cycle and that glutamate synthesis takes place through the coupling of the NADP-linked isocirate and glutamate dehydrogenase. It was shown that about 14% of total free amino acids of yeast cells was decreased by heat shock. Especially heat shock condition resulted in the marked decreases of serine family amino acids such as serine, glycine and cysteine, and in the considerable increases of the rates of methionine, alanine, glutamin.

• YAKHAK HOEJI
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• v.32 no.6
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• pp.377-385
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• 1988

The biologically active component of licoris(Glycyrrhizae Radix L.) is considered to be glycyrrhetinic acid, an aglycone of glycyrrhizin, on the basis of chemical and pharmacological studies. The present study was undertaken to investigate the effect of glycyrrhetinic acid on the hepatic morphine-6-dehydrogenase activity, which catalize morphine to morphinone. Morphine-6-dehydrogenase was further purified by centrifugation, $(NH_4)_2SO_4$ fractionation, sephadex G-100, hydroxyapatite column. Hepatic morphine-6-dehydrogenase activity was significantly decreased by the treatment of glycyrrhetinic acid. When effect of glycyrrhetinic acid on the hepatic morphine-6-dehydrogenase was investigated in vitro, it was powerfully inhibited the enzyme activity with dose-dependent manner. From the above results, glycyrrhetinic acid inhibits hepatic morphine-6-dehydrogenase activity and decreases the morphine induced harmful side effects.

• Biomedical Science Letters
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• v.20 no.3
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• pp.124-128
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• 2014

Alcoholism is a significant global health problem. Alcohol dehydrogenase and aldehyde dehydrogenase play important roles in the metabolism of alcohol and aldehyde. In this study, we aimed to investigate the eliminatory effects of a fruit extract drink on alcohol metabolism in drunken Sprague-Dawley (SD) rats. Male SD rats were given a fruit extract drink or a commercial product (10 mL/kg) 30 min prior to 40% (5 g/kg) ethanol ingestion. To assay the effect of the fruit extract drink on blood ethanol concentration, blood samples were taken from the saphenous vein at 3 and 5 h after ethanol ingestion. The blood concentrations of alcohol, alcohol dehydrogenase, and aldehyde dehydrogenase were significantly lower in the fruit extract drink group than in the control group, in a time-dependent manner. However, the alanine aminotransferase and aspartate aminotransferase activities of all experimental groups were unaltered compared to those of the control group. These results suggested that fruit extract drink intake can have a positive effect on the reduction of alcohol, alcohol dehydrogenase, and aldehyde dehydrogenase concentrations in the blood and may alleviate acute ethanol-induced hepatotoxicity by altering alcohol metabolic enzyme activities.

• Journal of Food Hygiene and Safety
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• v.18 no.3
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• pp.146-152
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• 2003

Pyruvate dehydrogenase phosphatase (PDP) is a mitochondrial protein serine/threonine phosphatase that catalyzes the dephosphorylation and concomitant reactivation of the pyruvate dehydrogenase component of the pyruvate dehydrogenase complex (PDC). PDP consists of a catalytic subunit (PDPc, Mr 52,600) and regulatory subunit (PDPr, Mr 95,600). In the presence of $Ca^{2+}$, PDPc binds to the dihydrolipoamide acetyltransferase (E2) component of the pyruvate dehydrogenase complex in proximity to its substrate, the phosphorylated E1 component, thereby increasing the rate of dephosphorylation. PDPc possesses and intrinsic $Ca^{2+}$ binding site and a second $Ca^{2+}$ site is generated in the presence of E2. Using the unique interaction, highly pure PDPc was produced by the GSH-Sepharose-GST-L2 matrix with a specific activity of approx. 1000 U/mg and a yield of about 80%.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.669-673
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• 2002

An extracellular limonoate dehydrogenase was purified 10-fold from a cell-free extract of Rhodococcus fascians by ammonium sulfate precipitation, dialysis, and ultrafiltration. This purified dehydrogenase catalyzed the conversion of limonoate to 17-dehydrolimonoate. The enzyme showed optimum activity at pH 8.0 and $40^{\circ}C$, with $K_m$ value of 0.9$\muM$, and requires Zn ions and sulfhydryl groups for catalytic action. The enzyme activity was inhibited by $Hg^{2+}\;and\;NaN_3$ ions. The degradation of limonin (66%) in Kinnow mandarin juice was successfully demonstrated with partially purified limonoate dehydrogenase. With scale-up preparation of limonoate dehydrogenase, a successful debittering operation of fruit juices appears feasible.

• Journal of Microbiology
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• v.40 no.1
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• pp.43-50
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• 2002

A cluster of genes encoding the pyruvate dehydrogenase complex (PDC) of Streptomyces seoulensis, a Gram-positive bacterium, was cloned and sequenced. The genes of S. seoulensis consist of four open reading frames. The first gene, lpd, which encodes a lipoamide dehydrogenase, is followed by pdhB encoding a dihydrolipoamide acetyltransferase (E2p), pdhR, a regulatory gene, and pdhA encoding a pyruvate dehydrogenase component (Elp). Elp had an unusual homodimeric subunit, which has been known only in Gram-negative bacteria S. seoulensis E2p contains two lipoyl domains like those of humans and Streptomyces faecalis. The pdhR gene appears to be clustered with the structural genes of S. seoulensis PDC. The PdhR-overexpressed S. seoulensis howed growth retardation and the decrease of Elp, indicating that PdhR regulates the function of PDC by repressing the expression of Elp. A strain of Streptomyces licidans overexpressing S. seoulensis PdhR showed a significant decreasein the level of actinorhodin, implying a regulatory role for Streptomyces PDC in antibiotic biosynthesis.