• Horticultural Science & Technology
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• v.35 no.4
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• pp.410-417
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• 2017

We compared the quality of 'Fuji' apples (Malus ${\times}$ domestica) from trees whose leaves were not removed (no artificial defoliation; NAD) with apples from trees that underwent early defoliation (ED, treated in mid September and early October) and conventional defoliation (CD, treated in early and mid October). The experiment was conducted in three consecutive years using 15-year-old 'Fuji' apple grafted on Malus prunifolia. Fruits were harvested on November 7, 16 or 12 in 2011, 2012 and 2013, respectively. Compared to NAD treatment, ED and CD treatment reduced the fresh weight by 4.7% and 0.6%, respectively. The soluble solids content of NAD apples ($14.4^{\circ}Brix$) was slightly higher than that of CD ($14.1^{\circ}Brix$) and ED ($14.0^{\circ}Brix$) apples. Soluble sugar content, flesh firmness, water-core index, and titratable acidity were not affected by defoliation treatment regardless of treatment timing. The skin blush index of NAD apples (2.3) was inferior to that of CD (3.3) and ED (3.4)- treated apples. Furthermore, artificial defoliation treatments increased skin redness ($a^*$) and yellowness ($b^*$) and significantly improved the degree of skin blush compared to NAD fruits.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2863-2866
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• 2014

• The Microorganisms and Industry
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• v.25 no.1
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• pp.2-9
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• 1999

A study was made on enzymes of carbohydrate metabolism in T. concretivorus grown with and without glucose. The present results show that T. concretivorus possesses high activities of pentose shunt pathway and related enzymes, glucokinase, G-6-P dehydrogenase, 6-PG dehydrogenase, and phosphoglucoisomerase, but low activities of enzymes unique to EMP(fructose-1,6-diphosphate aldolase). Although the synthesis of the latter enzymes remains largely unaffected by the growth enviroment, that of the former is stimulated by glucose. And the failure to detect ED pathway enzymes in cells grown in thiosulate or thiosulfate-glucose medium eliminates the ED pathway as a significant route of glucose catabolism in T.concretivorus. These results suggest that pentose shunt pathway performs an energetic role in glucose metabolism by T.concretivorus with EMP as a subway. The absence of ED pathway and the presence of pentose shunt pathway which is the major route of catabolism in T.concretivorus are similar to those of other obligately chemolitho-trophic thiobacilli. The G-6-P and 6-PG dehydrogenase are both NAD and NADP specific, but MAD predominant. However, the 3-PGAL dehydrogenase is only NAD specific. Since the specific activity of 3-PGAL generated from glucose is converted mainly into pyruvate which is channeled into the TCA cycle. All enzymes of the TCA cycle tested and NADH oxidase are detected in the cells of T.concretivorus grown in thiosulfate. The specific activities of fumarase and isocitrate dehydrogenase are high and others are low. The presence of two isocitrate dehydrogenase (NAD-and NADP-linked) may have important regulatory function for this organism. The activity of NAD-oxidase, which is implicated in the energy generating metabolism, was very high in the crude cell-free extract of T.concretivorus, recording 55.11 m.mu. mole/min/mg protein. This well coincides with the fact that activities of NAD-linked G-6-P dehydrogenase, 6-PG dehydrogenase and 3-PGAL dehydrogenase were high.

• Korean Journal of Microbiology
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• v.11 no.1
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• pp.1-18
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• 1973

A study was made on enzymes of carbohydrate metabolism in T. concretivorus grown with and without glucose. The present results show that T. concretivorus possesses high activities of pentose shunt pathway and related enzymes, glucokinase, G-6-P dehydrogenase, 6-PG dehydrogenase, and phosphoglucoisomerase, but low activities of enzymes unique to EMP(fructose-1, 6-diphosphate aldolase). Although the synthesis of the latter enzymes remains largely unaffected by the growth enviroment, that of the former is stimulated by glucose. And the failure to detect ED pathway enzymes in cells grown in thiosulate or thiosulfate-glucose medium eliminates the ED pathway as a significant route of glucose catabolism in T.concretivorus. These results suggest that pentose shunt pathway performs an energetic role in glucose metabolism by T.concretivorus with EMP as a subway. The absence of ED pathway and the presence of pentose shunt pathway which is the major route of catabolism in T.concretivorus are similar to those of other obligately chemolitho-trophic thiobacilli. The G-6-P and 6-PG dehydrogenase are both NAD and NADP specific, but MAD predominant. However, the 3-PGAL dehydrogenase is only NAD specific. Since the specific activity of 3-PGAL generated from glucose is converted mainly into pyruvate which is channeled into the TCA cycle. All enzymes of the TCA cycle tested and NADH oxidase are detected in the cells of T.concretivorus grown in thiosulfate. The specific activities of fumarase and isocitrate dehydrogenase are high and others are low. The presence of two isocitrate dehydrogenase (NAD-and NADP-linked) may have important regulatory function for this organism. The activity of NAD-oxidase, which is implicated in the energy generating metabolism, was very high in the crude cell-free extract of T.concretivorus, recording 55.11 m$\mu$ mole/min/mg protein. This well coincides with the fact that activities of NAD-linked G-6-P dehydrogenase, 6-PG dehydrogenase and 3-PGAL dehydrogenase were high.

• Journal of Preventive Medicine and Public Health
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• v.3 no.1
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• pp.111-119
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• 1970

Alterations of H-and M-isozymes of Lactic Dehydrogenase(LDH) were observed in the various tissues after exposing the rats to 50ppm and 250ppm of sulfur dioxide. These isozymes of the respective tissue were separated by Diethlaminoethyl (DTAE)-cellulose from the tissue homogenates of brain, lung and muscle, presenting the activities by rate of reduction of nicotinamide-adenine-dinucleotide ($NAD^+$). Pure LDH and the coenzyme ($NAD^+$) were directly treated with sulfur dioxide in vitro in order to find out the direct to sulfur dioxide on LDH and $NAD^+$ and the results were as follows. 1. In the normal tissues, the H-isozyme activity was dominant in the brain and heart, and the M-isozyme in the muscle. 2. In the lung tissue of normal rats, there was no difference between the activity of H-and M-type of LDH. 3. When rats inhale sulfur dioxide gas in concentration of 50ppm and 250ppm, it appeared that the H-type tend to be suppressed in aerobic tissues and the M-type in anaerobic tissues. 4. In the lung tissue exposed to sulfur dioxide, both the LDH activities were suppressed. 5. It seems that LDH and the coenzyme ($NAD^+$) are not directly affected by exposing in sulfur dioxide gas.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.213-218
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• 2010

Lactate dehydrogenases (LDHs) have been highly focused for long time, due to their important roles in biochemical and metabolic pathways of cells. On the basis of genome-wide searching results, three putative LDH genes from Bacillus cereus ATCC 14579 genome have been PCR-amplified, cloned, and well-expressed in E. coli. All three BcLDH isozymes are supposed to share highly conserved catalytic amino acid residues in common $NAD^+$-dependent LDHs. Meanwhile, BcLDH1 consisting of 314 amino acids shares 86 and 49% of identities with BcLDH2 and 3, respectively. Interestingly, only BcLDH1 showed the converting activities between L-lactate and pyruvate in the presence of $NAD^+$ coenzyme, while the other isozymes are likely to have almost no activity. As a result, it was revealed that BcLDH1 can be a typical $NAD^+$-dependent L-lactate-specific dehydrogenase.

• YAKHAK HOEJI
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• v.36 no.5
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• pp.469-473
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• 1992

Yeast alcohol dehydrogenase (YADH) has an acidic residue that interacts with the 2'- and 3'-hydroxyl groups of the adenosine ribose of the $NAD^+$ coenzyme. The acidic residue of Asp-223 (according to horse liver alcohol dehydrogenase amino acid sequence) is supposed to determine the coenzyme specificity for $NAD^+$ rather than $NADP^+$. We mutated Asp-223 to leucine and the mutant YADH was expressed in yeast and characterized for the coenzyme specificity. The turnover numbers of mutant enzyme for $NAD^+$ and ethanol were decreased 3.5- and 4.8-fold compared to wild-type enzyme, respectively. Contrastively, catalytic specificity for $NADP^+$ was increased 13-fold. As a result, the mutant YADH also employed $NADP^+$ as a coenzyme.

• Biodesign
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• v.7 no.1
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• pp.24-27
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• 2019

Pnc1 converts nicotinamide to nicotinic acid to generate NAD⁺ through the Preiss-Handler pathway that is one of the NAD⁺-salvage pathway. By reducing levels of nicotinamide, an inhibitor of the NAD⁺-dependent histone deacetylase Sir2, yeast Pnc1 contributes gene silencing. In this study, to understand the structural features and molecular mechanism of nicotinamidase Pnc1, we overexpressed, purified, and crystallized the N-terminally His₆-tagged Pnc1 protein from Kluyveromyces lactis and obtained X-ray diffraction data at a resolution of 2.2 Å. The crystals of the K. lactis Pnc1 (KlPnc1) belonged to space group P2₁2₁2₁ with unit cell parameters a=38.5, b=77.3, c=83.3, and α=β=γ= 90°. There is one molecule in the asymmetric unit.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.554-558
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• 2000

Synthesized 5-arylamino-2-methyl-4,7-dioxobenzothiazoles 3a-3o were evaluated for modulation of NAD(P)H: quinone oxidoreductase (NQOl) activity with the cytosolic fractions derived from cultured human lung cancer cells and their cytotoxicity in cultured several human solid cancer cell lines. The 4,7-dioxobenzothiazoles affected the reduction potential by NQOl activity and showed a potent cytotoxic activity against human cancer cell lines. The tested compounds 3a, 3b, 3g, 3h, 3n and 3o were considered as more potent cytotoxic agents, and comparable modulators of NQOl activity.

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.119-123
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• 1994

The synthesis of 3a, 3b, 7a fro Benzpthiazepinone and 1,4-dihyropyridine derivatives is described. Benzothiazepinone nad 1,4-dihydropyridine derivatives were prepared according to literature procedure. The key reactions involve esterification and amidation of benzothize-pinone nad 1,4-dihydropyridine derivatives.