• BMB Reports
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• v.32 no.1
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• pp.76-81
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• 1999

Dihydrolipoamide dehydrogenase (E3) belongs to the protein family of pyridine nucleotide-disulfide oxidoreductases, including glutathione reductase (GR). The two subunits of human GR are covalently linked by an intersubunit disulfide bond between the pair of the Cys-90 residues. The corresponding residue (Ser-79) in human E3 was substituted to Cys using site-directed mutagenesis. The mutant was expressed in Escherichia coli and highly purified using an affinity column. About 40% of the mutants formed a spontaneous intersubunit disulfide bond linkage. This result implies that Ser-79 and possibly surrounding residues constitute one of the several intersubunit contact regions in human E3. It provides another good piece of evidence for the predicted high degree of the structural homology between human E3 and GR. Spectroscopic studies indicate conformational changes in the mutant.

• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.171-175
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• 1995

Effects of $Biozyme_{R}$ and $\textrm{Business}_{R}$ on alcohol metabolism in rats, and on the activities of alcohol dehydrogenase(ADH) and acetaldehyde dehydrogenase(ALDH) were studied in vitro. Alcohol concentration in rat blood was decreased after the treatment of Business(3.3 mι/kg, Biozyme 1.67 mg/wι) and Biozyme(3.3 mι/kg, 1.67 mg/mι) prior to the administration of ethanol(25%, 0.83 g/kg). And the acetaldehyde concentration of rat blood was also decreased when compared with control values in the same condition. Effects of Biozyme on ADH and ALDH activity were also studied. While the ALDH activity was elevated in the presence of Biozyme(2 $\mu\textrm{g}$/assay), the ADH activity was not influenced by Biozyme at the concentration range from 2 $\mu\textrm{g}$/assay to 0.2 mg/assay. In summary, Biozyme accelerated the rate of ethanol metabolism and the acceleration might be due to the increase in ALDH activity.vity.

• The Korean Journal of Zoology
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• v.15 no.4
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• pp.193-205
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• 1972

Lactate and malate dehydrogenase isozymes in crude extracts of various tissues from 28 avian species were investigated by means of celluose acetate electrophoresis. In a given species the presence of two types of the malate dehydrogenase isozymes could be revealed in somatic tissues; one was characterized by fast electrophoretic mobility, and the other by slow mobility. Although the bird lactate dehydrogenase isozymes existed in a variety of species-specific molecular forms, they seemed to show the same pattern within the same genus and family.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.1 no.1
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• pp.5-12
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• 2001

아시아 및 한국에서 처음 발견된 3명의 소아 Ethylmalonic encephalopathy (EE) 환자들은 riboflavin을 이용한 치료법에 점진적인 호전을 보인 것으로 나타났다. Ethylmalonic aciduria가 3가지 효소-2-methyl-branched-chain acyl CoA dehydrogenase (2MBCAD), iso-valeryl CoA dehydrogenase (IVCAD), 그리고 short-chain acyl CoA dehydrogenase (SCAD) - 들의 부분적인 결함으로 생긴다는 가설하에 dehydrogenase (탈수효소)의 보조 효소인 riboflavin이 부분적으로 나마 치료 과정에서 어떤 역할을 수행하는지의 여부를 살펴보았다. 다음의 세 증례에서 riboflavin 혹은 coenzyme Q10을 병행하여 치료한 결과 인지 행동(cognitive behavior)과 만성 점액성 설사(chronic mucoid diarrhea)가 호전된 것으로 관찰되었다. 또한, 치료 후 운동 기능도 일부 호전되었다. EE의 질병 발생 기전이 현재까지 완전히 밝혀지지는 않았지만, 세 명의 EE 환자들의 치료경과를 관찰하여 위의 가설을 뒷받침 할 수 있었다.

• Journal of Plant Biology
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• v.16 no.1_2
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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.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.502-506
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• 1996

Protein X is one of the subunits of pyruvate dehydrogenase complex. The biological role of this protein has not been fully elucidated, mainly because of the difficulty in its dissociation from the tightly bound dihydrolipoamide acetyltransferase-protein X subcomplex. We have found that the detachment of protein X from acetyltransferase subunit can be easily accomplished by the cycles of freezing and thawing proces. Several lines of evidence including sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequence analysis and acetylation with $[2^{14}C]$ pyruvate confirmed that the purified protein is protein X. The purified intact form of protein X was acetylated by $[2^{14}C]$ pyruvate in the presence of py-ruvate dehydrogenase subunit.The acetylation efficiency of this protein was lower than that of acetyltransferase and was not affected by the presence of acetyltransferase.

• Biotechnology and Bioprocess Engineering:BBE
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• v.3 no.1
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• pp.15-18
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• 1998

The entanol productivity of superoxide dismutase (SOD)-deficient mutants of Saccharo-Myces cerevisiae was examined under the oxidative stress by Paraquat. It was observed that MnSOD-deficient mutant of S. cerevisiae had higher ethanol productivity than wild type or CuZnSOD-deficient yeast both in aerobic and in anaerobic culture condition. Pyruvated dehydrogenase activity decreased by 35% and alcohol dehydrogenase activity increased by 32% were observed in MnSOD-deficient yeast grown aerobically. When generating oxygen radicals by Paraquat, the ehanol productivity was increased by 40% in CuZnSOD-deficient or wild strain, resulting from increased activity of alcohol dehydrogenase and decreased a activity of pyruvate dehydrogenase. However, the addition of ascorbic acid with Paraquat returned the enzyme activities at the level of control. These results imply that SOD-deficiency in yeast strains may cause the metabolic flux to shift into anaerobic ethanol fermentation in order to avoid their oxidative damages by Paraquat.

• Environmental Engineering Research
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• v.23 no.3
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• pp.282-287
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• 2018

Three different methods of bacterial viability monitoring were compared to detect chemically or thermally inactivated Escherichia coli. Direct colony enumeration, live/dead bacterial cell staining with a fluorescent dye, and the dehydrogenase activity assay were compared with respect to their ease of use and time required to perform the three different tests. The green (live cell)/red (dead cell) ratio obtained from the fluorescent bacterial cell staining approach showed a linear relationship with the colony forming units; the result obtained with dehydrogenase was similar to those. The sensitivity of the monitoring methods to detect bacterial deactivation varied with different disinfection conditions. After thermal treatment, the sensitivity of the staining approach was lower, while that of the dehydrogenase activity assay was the highest. After chemical treatment, the sensitivity of detection for both methods was similar.

• Natural Product Sciences
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• v.18 no.3
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• pp.190-194
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• 2012

The effects of methanol extract of the leaves of Brassica juncea and its major component, isorhamnetin 3-O-${\beta}$-D-glucopyranoside on hepatic alcohol metabolizing enzymes were investigated. The methanol extract and isorhamnetin 3-O-${\beta}$-D-glucopyranoside supplementations increased the activities of microsomal ethanol oxidizing system and aldehyde dehydrogenase in a dose-dependent manner, and had mild effects on the activities of alcohol dehydrogenase and catalase. Isorhamnetin 3-O-${\beta}$-D-glucopyranoside alleviated the adverse effect of ethanol ingestion by enhancing the activities of alcohol oxidizing emzymes, microsomal ethanol oxidizing system and aldehyde dehydrogenase.

• Journal of Microbiology
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• v.38 no.4
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• pp.209-217
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• 2000

Mycobacterium sp. strain JCl DSM 3803 grown in methanol showed no methanol dehydrogenase or oxidase activities found in mast methylotrophic bacteria and yeasts, respectively. Even though the methanol-grown cells exhibited a little methanol-dependent oxidation by cytochrome c-dependent methanol dehydrogenase and alcohol dehydrogenase, they were not the key enzymes responsible for the methanol oxidation of the cells, in that the cells contained no c-type cytochrome and the methanol oxidizing activity from the partially purified alcohol dehydrogenase was too low, respectively. In substrate switching experiments, we found that only a catalase-peroxidase among the three types of catalase found in glucose-grown cells was highly expressed, in the methanol-grown cells and that its activity was relatively high during the exponential growth phase in Mycobacterium sp. JCl. Therefore, we propose that catalase-peroxidase is an essential enzyme responsible for the methanol metabolism directly Of indirectly in Mycobacterium sp. JCl.