• BMB Reports
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• v.47 no.9
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• pp.494-499
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• 2014

NADH:quinone oxidoreductase 1 (NQO1) is known to be involved in the regulation of energy synthesis and metabolism, and the functional studies of NQO1 have largely focused on metabolic disorders. Here, we show for the first time that compared to NQO1-WT mice, NQO1-KO mice exhibited a marked increase of permeability and spontaneous inflammation in the gut. In the DSS-induced colitis model, NQO1-KO mice showed more severe inflammatory responses than NQO1-WT mice. Interestingly, the transcript levels of claudin and occludin, the major tight junction molecules of gut epithelial cells, were significantly decreased in NQO1-KO mice. The colons of NQO1-KO mice also showed high levels of reactive oxygen species (ROS) and histone deacetylase (HDAC) activity, which are known to affect transcriptional regulation. Taken together, these novel findings indicate that NQO1 contributes to the barrier function of gut epithelial cells by regulating the transcription of tight junction molecules.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.239-245
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• 1998

To investigate the formation of bound residue with soil organic materials by oxidative coupling, nitroaromatics and their reduced metabolites, the insecticide parathion and the herbicide asulam were incubated with oxidoreductase, laccase or horseradish peroxidase, in the presence or absence of humic monomers. Most of aminotoluenes and amino-nitrophenols were completely transformed while most of nitrotoluenes and nitrophenols remained unchanged by a lactase or horseradish peroxidase in the presence or absence of humic monomers. Amino-nitrotoluenes were not transformed without humic monomers, but the addition of various humic monomers caused a considerable difference in the transformation of amino-nitrotoluenes by a lactase or horseradish peroxidase. Amino-nitrotoluenes were most transformed in the presence of catechol, syringaldehyde and protocatechuic acid. The insecticide parathion with nitro group and its metabolite were not mostly transformed in the presence or absence of humic monomers. The herbicide asulam with amino group remained unchanged without humic monomers as well, but the stimulating effect on the transformation of asulam was caused by the addition of catechol, syringaldehyde, protocatechuic acid or caffeic acid with a lactase.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.37-41
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• 1995

The effect of age on the metabolism of progesterone was studied in the rat brain. Metabolic activity was more active in minced tissues than total homogenates. The activity of progesterone $5{\alpha}-reductase(s)$ was increased during postnatal periods(between 5 and 14 days after birth) and thereafter steadily decreased up to the one-fourth level of the fetus. When $5{\alpha}-dihydroprogesterone$ was incubated with brain tissues of various ages, the change in the activity of $3{\alpha}-hydroxysteroid$ oxidoreductase$(3{\alpha}-HSOR)$ was similar to that of $5{\alpha}-reductase(s)$. These results suggest that the reduced formation of total $5{\alpha}-reduced$metabolites was due to the decreased activities of $5{\alpha}-reductase(s)$ and $3{\alpha}-HSOR$. However the level of $3{\beta}-HSOR$ remained constant regardless of the age.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.660-664
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• 2000

To clone genes related UK-58,852 production, genomic DNA of strain Actinodura roseorufa was used for the construction of genomic library using pOJ446 cosmid vector. The genomic library was screened rising dehydratase PCR product and eryA gene as a DNA hybridization probe. pHD54 was isolated, which contained an approximately 35kb of inserted DNA. BamHI, SmaI and sonicater fragments hybridized to eryA probe. All of pHD54 BgmHI, SmaI and sonicater fragments were subcloned into pGEM7 and some fragments which hybridized to eryA probe were sequenced. The nucleotide sequence was analysed using BLAST program. The sequence identities were observed in KS,AT, KR, ER and PKS loading domains. Also oxidoreductase showed similarity to rifamycin module10, and dTDP-D-glucose 4,6 dehydratase and TDP-D-glucose synthase involved in biosynthesis of sugar showed similarity to Streptomyces argillaceus.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2363-2367
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• 2014

The association between the NAD(P)H:quinone oxidoreductase 1 (NQO1) gene C609T polymorphism (rs1800566) and gastric cancer has been widely evaluated, but a definitive answer is so far lacking. We first conducted a case-control study to assess this association in a large Han Chinese population, and then performed a meta-analysis to further address this issue. Although our case-control association study indicated no significant difference in the genotype and allele distributions of C609T polymorphism between gastric cancer patients and controls, in the meta analysis involving 4,000 subjects, comparison of alleles 609T and 609C indicated a significantly increased risk (46%) for gastric cancer (95% confidence interval (95%CI) for odds ratio (OR)=1.20-1.79) in individuals with the T allele. The tendency was similar to the homozygote (OR=1.81, 95%CI: 1.16-2.84), dominant models (OR=1.41, 95%CI: 1.12-1.79), as well as recessive model (OR=1.58, 95%CI: 1.06-2.35). Stratified analysis by study design demonstrated stronger associations in population-based than in hospital-based studies. And ethnicity-based analysis demonstrated a significant association in Asians. We conclude that the NQO1 gene C609T polymorphism increases the risk for gastric cancer, especially in Asian populations.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.812-816
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• 1990

This study describes the sorbitol production with permeabilized cells of Zymomonas mobilis immobilized in Ca-alginate. Toluene treated cells lose activity of glucose-fructose oxidoreductase due to the leaking of enzyme from the cells. To prevent this leakage, the permeabilized cells were treated with 0.25% glutaraldehyde by stirring for 1 h at room temperature. A continuous process with glutaraldehyde treated cells was developed and no significant reduction in the degree of conversion occurred during 210 h operation. The productivities were estimated to be about $7.2{\sim}7.5\;g/l-h$ for sorbitol at dilution rate $0.18\;h^{-1}$.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.488-497
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• 1999

Probing Streptomyces albus ATCC 21838 chromosomal DNA with a proline tRNA sequence resulted in an isolation of a putative integrating element in the 6.4-kb EcoRI fragment. It was found that Streptomyces lividans TK-24 transformed with a cloned DNA fragment on a multicopy plasmid, produced a higher level of spore pigment and mycelial red pigment on a regeneration agar. Furthermore, the transformant S. lividans TK-24 produced a markedly increased level of undecylprodigiosin in a broth culture. A nucleotide sequence analysis of the cloned region revealed several open reading frames homologous to the integrases of integrating plasmids or temperate bacteriophages, signal-transducing regulatory proteins with a conserved ATP-binding domain, oxidoreductases ($\beta$-ketoacyl reductase), and an AraC-like transcriptional regulator. To examine the effect on antibiotic production, each coding region was overexpressed separately from the other genes in the region in S. lividans TK-24 with; pJHS3044 for the expression of the signal-transducing regulatory protein homologue, pJHS3045 for the homologue of oxidoreductase, and pJHS3051 for the homologue of the AraC-like transcriptional regulator. Phenotypic studies of S. lividans TK-24 strains harboring plasmids for the overexpression of individual genes suggested the following effects of the genes on antibiotic production: The oxidoreductase homologue stimulated the production of actinorhodin and undecylprodigiosin, which was influenced by the culture conditions; the homologue of the AraC-like transcriptional regulator was the most effective factor in antibiotic production within all the culture conditions tested; the signal-transducing regulatory protein homologue repressed the effect due to the homologue of the AraC-like transcriptional regulator, however, the antibiotic production was derepressed upon entering the stationary phase.

• Journal of Microbiology
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• v.40 no.2
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• pp.125-128
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• 2002

The aerobic respiratory chain of Vibrio alginolyticus possesses two different kinds of NADH oxidase systems, i.e., an $Na^{+}$-dependent NADH oxidase system and an $Na^{+}$-independent NADH oxidase system. When deamino-NADH, which is the only substrate for the $Na^{+}$-dependent NADH oxidase system, was used as a substrate, the maximum activities of $N^{+}$-dependent NADH: quinone oxidoreductase and $Na^{+}$-dependent NADH oxidase were obtained at about 0.06 M and 0.2 M NaCl, respectively. When NADH, which is a substrate for both $Na^{+}$-dependent and $Na^{+}$-independent NADH oxidase systems was used as a substrate, the NADH oxidase activity had a pH optimum at about 8.0. In cGntrastl when deamino-NADH was used as a substrate, the NADH oxidase activity had a pH optimum at about 9.0. On the other handle inside-out membrane vesicles prepared from the wild-type bacterium generated only a very small $\Delta$pH by the NADH oxidase system, whereas inside-out membrane vesicles prepared from Napl, which is a mutant defective in the $Na^{+}$ pump, generated $\Delta$pH to a considerable extent by the NADH oxidase system. On the basis of the results\ulcorner it was concluded that the respiratory chain-linked components of V. atginotyticus affect each other.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.79-91
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• 2021

γ-Glutamylcysteine synthetase (Gcs1) and glutathione reductase (Glr1) activity maintains minimal levels of cellular methylglyoxal in Candida albicans. In glutathione-depleted Δgcs1, we previously saw that NAD(H)-linked methylglyoxal oxidoreductase (Mgd1) and alcohol dehydrogenase (Adh1) are the most active methylglyoxal scavengers. With methylglyoxal accumulation, disruptants lacking MGD1 or ADH1 exhibit a poor redox state. However, there is little convincing evidence for a reciprocal relationship between methylglyoxal scavenger genes-disrupted mutants and changes in glutathione-(in)dependent redox regulation. Herein, we attempt to demonstrate a functional role for methylglyoxal scavengers, modeled on a triple disruptant (Δmgd1/Δadh1/Δgcs1), to link between antioxidative enzyme activities and their metabolites in glutathione-depleted conditions. Despite seeing elevated methylglyoxal in all of the disruptants, the result saw a decrease in pyruvate content in Δmgd1/Δadh1/Δgcs1 which was not observed in double gene-disrupted strains such as Δmgd1/Δgcs1 and Δadh1/Δgcs1. Interestingly, Δmgd1/Δadh1/Δgcs1 exhibited a significantly decrease in H2O2 and superoxide which was also unobserved in Δmgd1/Δgcs1 and Δadh1/Δgcs1. The activities of the antioxidative enzymes erythroascorbate peroxidase and cytochrome c peroxidase were noticeably higher in Δmgd1/Δadh1/Δgcs1 than in the other disruptants. Meanwhile, Glr1 activity severely diminished in Δmgd1/Δadh1/Δgcs1. Monitoring complementary gene transcripts between double gene-disrupted Δmgd1/Δgcs1 and Δadh1/Δgcs1 supported the concept of an unbalanced redox state independent of the Glr1 activity for Δmgd1/Δadh1/Δgcs1. Our data demonstrate the reciprocal use of Eapx1 and Ccp1 in the absence of both methylglyoxal scavengers; that being pivotal for viability in non-filamentous budding yeast.

• Animal Bioscience
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• v.37 no.2_spc
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• pp.396-403
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• 2024

Objective: Monofluoroacetate (MFA) is a potent toxin that blocks ATP production via the Krebs cycle and causes acute toxicity in ruminants consuming MFA-containing plants. The rumen bacterium, Cloacibacillus porcorum strain MFA1 belongs to the phylum Synergistota and can produce fluoride and acetate from MFA as the end-products of dehalorespiration. The aim of this study was to identify the genomic basis for the metabolism of MFA by this bacterium. Methods: A draft genome sequence for C. porcorum strain MFA1 was assembled and quantitative transcriptomic analysis was performed thus highlighting a candidate operon encoding four proteins that are responsible for the carbon-fluorine bond cleavage. Comparative genome analysis of this operon was undertaken with three other species of closely related Synergistota bacteria. Results: Two of the genes in this operon are related to the substrate-binding components of the glycine reductase protein B (GrdB) complex. Glycine shares a similar structure to MFA suggesting a role for these proteins in binding MFA. The remaining two genes in the operon, an antiporter family protein and an oxidoreductase belonging to the radical S-adenosyl methionine superfamily, are hypothesised to transport and activate the GrdB-like protein respectively. Similar operons were identified in a small number of other Synergistota bacteria including type strains of Cloacibacillus porcorum, C. evryensis, and Pyramidobacter piscolens, suggesting lateral transfer of the operon as these genera belong to separate families. We confirmed that all three species can degrade MFA, however, substrate degradation in P. piscolens was notably reduced compared to Cloacibacillus isolates possibly reflecting the loss of the oxidoreductase and antiporter in the P. piscolens operon. Conclusion: Identification of this unusual anaerobic fluoroacetate metabolism extends the known substrates for dehalorespiration and indicates the potential for substrate plasticity in amino acid-reducing enzymes to include xenobiotics.