• The Korean Journal of Zoology
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• v.9 no.2
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• pp.7-9
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• 1966

송충(Dendrolimus spectabilis)의 변태에 따른 succinic dehydrogenase 의 활성도를 Thunberg 관법을 이용하여 측정하였다. 일반적으로 생성도의 변동은 기관발생과 밀접한 관계를 가지고있으며 각 기관에 있어서의 활성도는 아래와같다. 1. Gut는 여러 기관중 제일 높은 활성도를 보여주며 fat body 와 더불어 U자 모양 curve의 활성도를 나타내고 있다. 2. Brain 과 testis 는 상승의 활성도를 보여주었다. 3. Body wall 과 verve cord의 활성도는 불규칙적이었다.

• Journal of Microbiology
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• v.37 no.1
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• pp.41-44
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• 1999

Human mitochondrial aldehyde dehydrogenase 2 (ALDH2) is mainly responsible for oxidation of acetaldehyde generated during alcohol oxidation in vivo. A full-length cDNA of human liver ALDH2 was successfully expressed using a vaccinia virus-T7 RNA polymerase system. The expressed ALDH2 had an enzymatic activity as high as the native human liver ALDH2 enzyme.

• BMB Reports
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• v.29 no.6
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• pp.493-499
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• 1996

The biochemical properties of purified D-hydruxyisovalerate dehydrogenase from Fusarium sambucinum was elucidated. D-Hydroxyisovalerate dehydrogenase produced solely D-hydroxyisovalerate from 2-ketoisovalerate. The isoelectric point of the purified enzyme was 7.0. The enzyme was highly specific with 2-ketoisovalerate ($K_{m}=0.188$ mM, $V_{max}=8.814$ mmol/min mg) and 2-keto-3-methyl-n-valerate ($K_{m}=0.4$ mM, $V_{max}=1.851$ mmol/min mg) for the reductive reaction. This was also seen by comparing D-hydroxyisovalerate ($K_{m}=1.667$ mM, $V_{max}=0.407$ mmol/min mg) and D-hydroxy-3-methyl-n-valerate ($K_{m}=6.7$ mM, $V_{max}=0.648$ mmol/min mg) for the oxidative reaction. Thiol blocking reagents, such as iodoacetamide, N-ethylmaleimide and p-chloromecuribenzoate inhibited about 80% of enzyme activity at 0.02 mM, 50 mM and 50 mM, respectively. The enzyme activity was also inhibited by the addition of 0.1 mM of various metal ions, such as $Fe^{2+}$ (67%), $Cu^{2+}$ (88%), $Zn^{2+}$ t (76%) and $Mg^{2+}$ (9%). The enzyme was stable over three months in 50 mM potassium phosphate buffer (pH 5~7) at $-80^{\circ}C$. However the purified enzyme lost 30% of its activity in the same buffer after 24 h at $4^{\circ}C$. The studies about thermal inactivation of D-hydroxyisovalerate dehydrogenase exhibit 209.2 kJ/M of activation enthalpy and 0.35 kJ/mol K of activation entropy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.594-599
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• 2012

The objective of this study was to determine the processing conditions for salt dried rockfish Sebastes schlegeli by sun drying and cold-air drying, as measured by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activity. We processed salt dried rockfish samples. The salinity of rockfish samples was within 1% following salting with 25% salt brine for 3 h. The moisture content of salt dried rockfish was found to reduce linearly from 70.12 to 39.5 g/100 g over the same time interval. The water activities of salt dried rockfish by sun and cold-air drying were 0.94 and 0.87, respectively, after three days of drying. Acid values (AV) were 10.71 and 5.96 mg KOH/g, respectively, after the three day drying period. The ADH activity in a water extract from salt dried rockfish following sun and cold-air drying for 24 h was 228.5% and 226.1% at 13.3 mg/mL, respectively, and was higher than that when drying lasted for 48 and 72 h. The ALDH activity was not affected but both ADH and ALDH activity tended to decrease as the drying time increased from 24 to 72 h. The conditions of processing for the best quality of salt dried rockfish were determined to be drying with a cold-air system for 24 h. These results indicated that water extracts from salt dried rockfish have valuable biological attributes owing to the metabolizing of alcohol and can provide useful information for the design of drying systems for salt dried rockfish.

• BMB Reports
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• v.38 no.2
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• pp.248-252
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• 2005

Dihydrolipoamide dehydrogenase (E3) catalyzes the reoxidation of dihydrolipoyl moiety of the acyltransferase components of three $\alpha$-keto acid dehydrogenase complexes and of the hydrogen-carrier protein of the glycine cleavage system. His-457 of Pseudomonas putida E3 is suggested to interact with the hydroxyl group of Tyr-18 of the other subunit and with Glu-446, a component in the last helical structure. To examine the importance of the suggested interactions in human E3 function, the corresponding residue of human E3, Asn-473, was substituted to Leu using site-directed mutagenesis. The E3 mutant was expressed in Escherichia coli and highly purified using an affinity column. Its E3 activity was decreased about 37-fold, indicating that Asn-473 residue was important to the efficient catalytic function of human E3. Its slightly altered spectroscopic properties implied that small conformational changes could occur in the E3 mutant.

• Journal of Microbiology
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• v.44 no.1
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• pp.50-53
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• 2006

Cys-29 and Cys-251 of Streptomyces albus valine dehydrogenase(ValDH) were highly conserved in the corresponding region of $NAD(P)^+$-dependent amino acid dehydroganase sequences. To ascertain the functional role of these cysteine residues in S. albus ValDH, site-directed mutagenesis was performed to change each of the two residues to serine. Kinetic analyses of the enzymes mutated at Cys-29 and Cys-251 revealed that these residues are involved in catalysis. We also constructed mutant ValDH by substituting valine for leucine at 305 by site-directed mutagenesis. This residue was chosen, because it has been proposed to be important for substrate discrimination by phenylalanine dehydrogenase (PheDH) and leucine dehydrogenase (LeuDH). Kinetic analysis of the V305L mutant enzyme revealed that it is involved in the substrate binding site. However it displayed less activity than the wild type enzyme toward all aliphatic and aromatic amino acids tested.

• Korean Journal of Pharmacognosy
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• v.25 no.2
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• pp.160-166
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• 1994

The possible mechanisms of ginseng saponins on the inhibition of the development of morphine tolerance and physical dependence were investigated in the aspects of morphine metabolism by morphine 6-dehydrogenase. The administration of morphine causes a reduction of non-protein sulfhydryl contents in the liver, because morphinone metabolized from morphine by morphine 6-dehydrogenase conjugates with sulfhydryl compounds. However, ginseng saponins inhibited the activity of morphine 6-dehydrogenase which catalyzed the production of morphinone from morphine. In addition, ginseng saponins inhibited the reduction of non-protein sulfhydryl levels by increasing the level of hepatic glutathione. These results suggest that the dual action of the above plays an important role in the inhibition of the development of morphine tolerance and physical dependence. On the other hand, it was observed that less polar components of ginseng saponins with parent structures were more active components in vitro.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.718-722
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• 1998

Scopoletin (7-hydroxy-6-methoxycoumarin), a coumarin, was isolated from the aerial part of Solanum lyratum Thunb. by the activity-guided fractionation employing carbon te trachloride-intoxicated primary cultured rat hepatocytes as a screening system. Its hepatoprotective activity was first evaluated by measuring the release of glutamic pyruvic transaminase and sorbitol dehydrogenase from carbon tetrachloride-intoxicated rat hepatocytes into the culture medium. Scopoletin significantly reduced the releases of glutamic pyruvic transaminase and sorbitol dehydrogenase from the carbon tetrachloride-intoxicated primary cultured rat hepatocytes by 53% and 58%, respectively, from the toxicity in a dose-dependent manner over concentration ranges of 1mcM to 50mcM. Further studies revealed that at the concentration of 10mcM, scopoletin significantly preserved glutathione content by 50% and the activity of superoxide dismutase by 36% and also inhibited the production of malondialdehyde to the degree as seen in the control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.1-5
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• 2010

Alcohol metabolizing activity of fermented sea tangle juice (FSYJ) using Lactobacillilus brevis BJ20 were evaluated by measuring relative alcohol dehydrogenease (ADH) and aldehyde dehydrogenase (ALDH) activities. According to the results of MTI assay. the fermented sea tangle juice by Lactobacillilus brevis BJ20 appeared safe in the cytotocxity. The relative ADH activity of FSTJ showed 124% at 10 mg/mL, which increased with increasing concentration. The relative ALDH activity showed, however, insignificant difference (P>0.05) between concentrations of FSTJ up to 50 mg/mL. These results suggested that fermented sea tangle juice by L. brevis BJ20 could be used as a potential material for metabolizing alcohol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.187-191
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• 1994

The present stduy was undertaken to investigate the possible effect of Puffer fish skin extract (Pf) on the heptic acetaldehyde metabolism . It was obsrved that PF markedly decreased the acetaldehyde levels in blood and liver. The activity of mitochondrial aldehyde dehydrogenase (Ald DH) increased by induction of acute intoxicatiion of alcohol (5 g/kg) was further increased through pretreatment with PF for 2 weeks. When PF was given to rat fed with 25% alcohol solution instead of water for 6 weeks. the activity of Ald DH in mitochondrial fraction decreased to about 28% compared with sucrose-treated group. But after pretreatemnt of PF, the activity was restored to the normal level. By the treatment with disulfiram (300 mg/kg, once a day for 3days) was restored to the control after the pretreatment with PF. And also mitochondrial Ald DH activity in vitro was not changed. All these observations suggest that reduction of acetaldehyde levels are partly due to increase activity of mitochondrial Ald DH. Therefore, the recovery from intoxication of acetaldehyde may be enhanced by treatment with PF.