• Journal of the Korean Chemical Society
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• v.63 no.2
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• pp.134-137
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• 2019

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.153-159
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• 2013

A mannitol dehydrogenase (MDH; EC 1.1.1.67) gene was cloned from the Sinorhizobium meliloti 1021 (KCTC 2353) genome and expressed in Escherichia coli. It was seen to have an open reading frame consisting of 1,485 bp encoding 494 amino acids (about 54 kDa), which shares approximately 35-55% of amino acid sequence identity with some known long-chain dehydrogenase/ reductase family enzymes. The recombinant S. meliloti MDH (SmMDH) showed the highest activity at $40^{\circ}C$, and pH 7.0 (D-fructose reduction) and pH 9.0 (D-mannitol oxidation), respectively. SmMDH could catalyze the oxidative/reductive reactions between D-mannitol and D-fructose in the presence of $NAD^+/NADH$ as a coenzyme, but not with NADP+/NADPH. These results indicate that SmMDH is a typical $NAD^+/NADH$-dependent mannitol dehydrogenase.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.156-162
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• 2012

A mannitol dehydrogenase (StMDH) gene was cloned from Salmonella typhimurium LT2 (KCTC 2421) and overexpressed in Escherichia coli. It has a 1,467 bp open reading frame encoding 488 amino acids with deduced molecular mass of 54 kDa, which shares approximately 36% of amino acid identity with known long-chain dehydrogenase/reductatse (LDR) family enzymes. The recombinant StMDH showed the highest activity at $30^{\circ}C$, and pH 5.0 and 10.0 for D-fructose reduction and D-mannitol oxidation, respectively. On the contrary, it has no activity on glucose, galactose, xylose, and arabinose. StMDH can catalyze the oxidative/reductive reactions between D-fructose and D-mannitol only in the presence of $NAD^+$/NADH as coenzymes. These results indicate that StMDH is a typical $NAD^+$/NADH-dependent mannitol dehydrogenase (E.C. 1.1.1.67).

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.200-207
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• 2009

In this study, the characterization of purified erythritol 4-phosphate dehydrogenase, key enzyme of erythritol biosynthesis, produced by Penicillium sp. KJ81 was investigated. Optimum production conditions of erythritol 4-phosphate dehydrogenase was 1 vvm areration, 200 rpm agitation, at $37^{\circ}C$ for 8 days in the medium containing 30% sucrose, 0.5% yeast extract, 0.5% $(NH_4)_2SO_4$, 0.1% $KH_2PO_4$, and 0.05%$MgCl_2$. Erythritol 4-phosphate dehydrogenase was purified through ultrafiltration and preparative gel electrophoresis from cell extract of Penicillium sp. KJ81. This enzyme was especially active on erythrose 4-phosphate with 1.07 mM of Km value. It gave a single band on native polyacrylamide gel electrophoresis and an isoelectric point of 4.6. The enzyme had an optimal activity at pH 7.0 and $30^{\circ}C$. It was stable between pH 4.0 and 9.0, and also below $30^{\circ}C$. The enzyme activity was completely inhibited by 1mM $Cu^{2+}$ and 1 mM $Zn^{2+}$, but was not significantly affected by other cations tested. This enzyme was inactivated by treatment of tyrosine specific reagent, iodine and tryptophan specific reagent, N-bromosuccinimide. The substrate of the enzyme, erythrose 4-phosphate showed protective effect on the inactivation of the enzyme by both reagents. These results suggest that tryptophan and tyrosine residues are probably located at or near active site of the enzyme.

• Korean Journal of Microbiology
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• v.21 no.4
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• pp.221-228
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• 1983

An improved procedure for the rapid purification of glucose-6-phosphate dehydrogenase from extracts of Saccharomyces cerevisiae was developed by using affinity chromatography. Among six affinty media tested, $NADP^+ -agarose$ and Affi-gel Blue were more effective than others (i.e., Affi-gel Red, AMP-agarose, ATP-agarose, and $NAD^+ -agarose$). Conditions to desorb the enzyme bound to the affinity media were examined to increase the purity as well as yield. The best result was obtained when the column was developed with a linear gradient of KCl (0-1.0M). In case of Affi-gel Blue, introduction of $NAD^+$ (15mM) washing step prior to the salt gradient was most effective to remove $NAD^+ -binding$ proteins. For a large scale preparation of G-6-P dehydrogenase higher recovery was obtained by Affi-gel Blue than $NADP^+ -agarose$, however, the purity of the enzyme was decreased by 10 times if the former was used as the affinity medium. The capacity of Affi-gel Blue for G-6-P dehydrogenase was found to be 5 times higher than that of $NADP^+ -agarose$. Furthermore Affi-gel Blue could be reused repeatedly and its preparation is relatively easier and less expensive than $NADP^+ -agarose$.

• BMB Reports
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• v.28 no.5
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• pp.408-413
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• 1995

Decrease in the amount of cotyledonary spermidine in Glycine max under anaerobic conditions related to an increase in spermidine dehydrogenase. Under the same conditions, no enzymatic activity of diamine oxidase was observed. Exposure of Glycine max both to spermidine and 1,3-diaminopropane under anaerobic conditions resulted in a decrease in spermidine contents. Correlated with the decrease in spermidine contents, there was a drastic increase in spermidine dehydrogenase. The molecular weight of the purified enzyme estimated by Sephacryl S-300 gel column and SDS gel electrophoresis were 130,000 dalton and 65,000 dalton, respectively, indicating that the enzyme is a dimer. The optimal pH for activity was 9.3. The $K_m$ value for spermidine was 0.61 mM. Neither metal ions nor polyamine and derivatives affected enzymatic activity, but the enzyme was inhibited by DTNB, NEM and PCMB, suggesting that a cysteine residue of the enzyme is associated with or involved in enzyme activity. To our knowledge, this is the first report describing properties of the enzyme from plants. Considered together, the data in this paper indicate that both spermidine and 1,3-diaminopropane, novel activators, enhance the spermidine dehydrogenase activity and control the intracellular spermidine contents.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.27-32
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• 1980

We isolated a strain of Pseudomonas sp. from soil to utilize furfuryl alcohol as a carton source by enrichment culture. Alcohol dehydrogenase from this bacteria was purified 700-fold by Sephadex G-200 and affinity column chromatography to be homogeneous by electrophoresis and analytical centrifugation. This enzyme had a molecular weight of 120,000 and was composed of four subunits consisting of 266 amino acid residues. The optimal pH of the enzyme was pH 8.5 to 9, and the optimal temperature was, 45$^{\circ}C$. This enzyme was stable at 55$^{\circ}C$, but lost 80% of its activity in 10min at 6$0^{\circ}C$.

• The Korean Journal of Mycology
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• v.17 no.1
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• pp.35-38
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• 1989

Gene libraries of DNA from Flammulina velutipes were constructed using Escherichia coli plasmid pBR 322. Leu 2 gene coding ${\beta}-isopropylmalate$ dehydrogenase from F. velutipes was cloned by complementation of leucine requiring mutant of E. coli. The size of inserted DNA fragment of this clone is about 1 Kbp. The fragment has Bam H1 and Ava 1 restriction sites.

• The Korean Journal of Mycology
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• v.17 no.1
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• pp.27-30
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• 1989

F. velutipes Leu 2 gene (${\beta}-isopropylmalate$ dehydrogenase gene) was used for transformation of P. florida leucine requiring auxotrophic mutant P101. Transformation frequency was very low but the transformed colony can grow on minimal medium very slowly. Transformation was identified by Southern hybridization and reverse transformation into E. coli using chromosome DNA isolated from transformed P. florida.

• YAKHAK HOEJI
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• v.38 no.4
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• pp.401-409
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• 1994

The cholinergic activity of dammarane glycosides of Panax ginseng was examined both morphologically and chemically on primary cultures of chicken embryonic brain cells. When primary cultured chicken embryonic cells were treated with $50\;{\mu}g/ml$ of total dammarane glycosides of Panax ginseng followed by the exposure to 10mM atropine for 48 hr, lactate dehydrogenase levels within the cells remained at 36% of untreated control values while atropine-treated controls fell to 0% lactate dehydrogenase. It was found that cholinergic activity was mainly exerted by the panaxadiol glycosides. The treatment of the cells with $50\;{\mu}g/ml$ of panaxadiol glycosides followed by the exposure to atropine, lactate dehydrogenase levels within the cells remained at 60% of untreated control values. Ginsenoside $Rb_1$, a component of panaxadiol glycosides, was found to exert the cholinergic activity keeping the lactate dehydrogenase levels within the cells at 70% of untreated control values. The cholinergic activity of ginsenoside $Rb_1$ seems to be exerted through acting on the $Ca^{2+}$ channel in cultured brain cells.