• Applied Biological Chemistry
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• v.27 no.3
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• pp.180-186
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• 1984

For the study of glucose oxidase(GOD) and catalase(CAT) coimmobilization system, the enzymes were obtained from Penicillium spp., PS-8, and the strain itself was used as an immobilizing matrix. To separate glucose oxidase and catalase after the ammonium sulfate fractionation of the culture broth, DEAF-cellulose column was used and its activity yield was 54 and 34%, respectively. Both enzymes were immobilized on the cell matrix, followed crosslinking with 2.5% glutaraldehyde for 12hr. In the determination of efficiencies of GOD and CAT of dual, mixed and soluble enzyme systems, the dual immobilized one w-as superior to those of the soluble or mixed ones. In the comparison of pH profiles, the dual and mixed types showed broader maximum pH ranges than the soluble type. Varying CAT/GOD ratio of the dual system, the higher the ratio showed the broader activity profile. In the comparison of apparent $K_m$ of GOD only and CAT/GOD=10, they were $7.1{\times}10^{-2}$ and $5.1{\times}10^{-2}M$. Their activation energies showed 3.98kcal/mole/deg for GOD only and 2.98kcal/mole/deg for CAT/GOD=10.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.37-40
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• 1985

The reactor performance of a coimmobilized glucose oxidase and catalase enzyme system was investigated. In the determination of efficiencies of glucose oxidase and catalase of dual, mixed and soluble systems, the dual type immobilized one was superior to either the soluble or to the mixed system. In the continuous plugflow bed reactor system of glucose oxidase and catalase, $k-d$, deactivation rare constant of glucose oxidase only and catalase/glucose oxidase = 10 were $1.12\;{\times}\;10^{-2}\;and\;2.17\;{\times}10^{-3}\;hr^{-1}$, respectively. In the effect of ${\tau}$, space time, the point of $O_2$ limitation is $5.5\;g{\cdot}hr/l$ in both catalase/glucose oxidase = 1 and 10. In the effect of $O_2$ concentration to reduce the $O_2$ diffusion limitation, it appeared that ${\tau}\;=\;8.3g{\cdot}r/l$ is the maximum point of $O_2$ concentration in both catalase/glucose oxidase = 1 and 10.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.1
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• pp.57-67
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• 2019

Particulate matters with a diameter of < $10{\mu}m$ (PM10) exert oxidative stress and inflammatory events in various organs. The purpose of this study was to examine the molecular mechanism of reactive oxygen species (ROS) production induced by PM10 in the human epidermal keratinocytes (HEKs). When cultured HEKs were exposed to PM10, ROS production was induced and it was inhibited by apocynin, an antioxidant. The mRNA expression of NADPH oxidase (NOX) family was analyzed in order to examine their role in PM10-induced ROS production. PM10 increased the mRNA expression of NOX1, NOX2, dual oxidase (DUOX) 1 and DUOX2. HEKs expressed DUOX1 and DUOX2 at higher levels compared to other NOXs. The mRNA expression of dual oxidase maturation factors, DUOXA1 and DUOXA2, was also increased by PM10. We examined whether these calcium-dependent enzymes, DUOX1 and DUOX2, mediate the PM10-induced ROS production. A selective intracellular calcium chelator, BAPTA-AM, attenuated ROS production induced by PM10 or calcium ionophore A23187. The small intereference RNA (siRNA)-mediated down-regulation of DUOX2, but not DUOX1, attenuated the ROS production induced by PM10. PM10 increased the expression of inflammatory cytokines such as interleukin $(IL)-1{\beta}$, IL-6, IL-8 and interferon $(IFN)-{\gamma}$. SiRNA-mediated down-regulation of DUOX2 suppressed the PM10-induced expression of $IFN-{\gamma}$ but not other cytokines. This study suggests that DUOX2 plays a crucial role in ROS production and inflammatory response in PM10-exposed keratinocytes.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.555-561
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• 1990

Aromas of sulfur-containing volatiles from two vegetable varieties of Cruciferae Brassica oleracea and the suppression of undesirable sulfurous aromas of cruciferous vegetables by sulfhydryl oxidase of caraway seeds were examined. Aroma components were separated by gas chromatography equipped with a dual flame photometric detector The volatile sulfides produced from cabbage and broccoli varied. in the relative quantities and rates of production. according to the amount of caraway seeds added and incubation time. The amount of methanethiol and dimethyl disulfide in the cabbage and broccoli with caraway seeds was far less than those in the cabbage and broccoli. Removal of methanethiol and dimethyl disulfide was proportional to the amount of caraway seeds added, and was remarkable with 2.5% aqueous slurries of caraway seeds added.

• Journal of Microbiology
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• v.44 no.3
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• pp.284-292
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• 2006

The cbb3 cytochrome c oxidase has the dual function as a terminal oxidase and oxygen sensor in the photosynthetic bacterium, Rhodobacter sphaeroides. The cbb3 oxidase forms a signal transduction pathway together with the PrrBA two-component system that controls photosynthesis gene expression in response to changes in oxygen tension in the environment. Under aerobic conditions the cbb3 oxidase generates an inhibitory signal, which shifts the equilibrium of PrrB kinase/phosphatase activities towards the phosphatase mode. Photosynthesis genes are thereby turned off under aerobic conditions. The catalytic subunit (CcoN) of the R. sphaeroides cbb3 oxidase contains five histidine residues (H2l4, B233, H303, H320, and H444) that are conserved in all CcoN subunits of the cbb3 oxidase, but not in the catalytic subunits of other members of copper-heme superfamily oxidases. H214A mutation of CcoN affected neither catalytic activity nor sensory (signaling) function of the cbb3 oxidase, whereas H320A mutation led to almost complete loss of both catalytic activity and sensory function of the cbb3 oxidase. H233V and H444A mutations brought about the partial loss of catalytic activity and sensory function of the cbb3 oxidase. Interestingly, the H303A mutant form of the cbb3 oxidase retains the catalytic function as a cytochrome c oxidase as compared to the wild-type oxidase, while it is defective in signaling function as an oxygen sensor. H303 appears to be implicated in either signal sensing or generation of the inhibitory signal to the PrrBA two-component system.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.165-170
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• 2023

Isolation of the culture broth of a marine-derived Acremonium sp. CNQ-049 guided by HPLC-UV yielded compound 1 (3-phenethyl-2-phenylquinazolin-4(3H)-one), and its inhibitory activities against monoamine oxidases (MAOs), cholinesterases (ChEs), and β-secretase 1 (BACE1) were evaluated. Compound 1 was an effective selective MAO-B inhibitor with an IC₅₀ value of 9.39 µM and a selectivity index (SI) value of 4.26 versus MAO-A. In addition, compound 1 showed a potent selective butyrylcholinesterase (BChE) inhibition with an IC₅₀ value of 7.99 µM and an SI value of 5.01 versus acetylcholinesterase (AChE). However, compound 1 showed weak inhibitions against MAO-A, AChE, and BACE1. The Ki value of compound 1 for MAO-B was 5.22±1.73 µM with competitive inhibition, and the Ki value of compound 1 for BChE was 3.00±1.81 µM with mixed-type inhibition. Inhibitions of MAO-B and BChE by compound 1 were recovered by dialysis experiments. These results suggest that compound 1 is a dual-functional reversible inhibitor of MAO-B and BChE, that can be used as a treatment agent for neurological disorders.

• Journal of Veterinary Science
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• v.23 no.1
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• pp.2.1-2.18
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• 2022

Background: Co-infections of the porcine reproductive and respiratory syndrome virus (PRRSV) and the Haemophilus parasuis (HPS) are severe in Chinese pigs, but the immune response genes against co-infected with 2 pathogens in the lungs have not been reported. Objectives: To understand the effect of PRRSV and/or HPS infection on the genes expression associated with lung immune function. Methods: The expression of the immune-related genes was analyzed using RNA-sequencing and bioinformatics. Differentially expressed genes (DEGs) were detected and identified by quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC) and western blotting assays. Results: All experimental pigs showed clinical symptoms and lung lesions. RNA-seq analysis showed that 922 DEGs in co-challenged pigs were more than in the HPS group (709 DEGs) and the PRRSV group (676 DEGs). Eleven DEGs validated by qRT-PCR were consistent with the RNA sequencing results. Eleven common Kyoto Encyclopedia of Genes and Genomes pathways related to infection and immune were found in single-infected and co-challenged pigs, including autophagy, cytokine-cytokine receptor interaction, and antigen processing and presentation, involving different DEGs. A model of immune response to infection with PRRSV and HPS was predicted among the DEGs in the co-challenged pigs. Dual oxidase 1 (DUOX1) and interleukin-21 (IL21) were detected by IHC and western blot and showed significant differences between the co-challenged pigs and the controls. Conclusions: These findings elucidated the transcriptome changes in the lungs after PRRSV and/or HPS infections, providing ideas for further study to inhibit ROS production and promote pulmonary fibrosis caused by co-challenging with PRRSV and HPS.