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Xanthine oxidase 활성 및 형전환에 미치는 구리이온의 영향
허근,이상일,박진우 영남대학교 약품개발연구소 1994 영남대학교 약품개발연구소 연구업적집 Vol.4 No.-
Copper intoxication and disturbance of copper metabolism induced various oxygen-derived free radicals related damages. The effect of copper ion on xanthine oxidase activity and type conversion of the enzyme which is concerned to generation of reactive oxygen species, was investigated. It was observed that xanthine oxidase activity was increased by addition of copper ion in the reaction mixture in proportional to the concentration of the metal ion until 60 μM, while the enzyme activity was inhibited in higher concentration of copper treatment. On the other hand, xanthine dehydrogenase activity was inhibited by copper ion addition with concentration dependently. Preincubation of enzyme source with 30 μM of copper ion, which concentration marked increased the xanthine oxidase activity, unchanged the enzyme activity and type conversion compare to control in vitro system. It was also observed that copper induced xanthine oxidase activity and the enzyme type conversion was protected by dithiothreitol and penicillamine. These results indicate that the increment of the type conversion of xanthine oxidase necessarilly need the presence of copper ion in enzyme assay system.
Park, Jeen-Woo,Lee, Soo-Min Korean Society for Biochemistry and Molecular Biol 1995 Journal of biochemistry and molecular biology Vol.28 No.3
The nonenzymatic glycation of copper, zinc-superoxide dismutase (Cu,Zn-SOD) led to inactivation and fragmentation of the enzyme. The glycated Cu,zn-SOD was isolated by boronate affinity chromatography. The formation of 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in calf thymus DNA and the generation of strand breaks in pBhiescript plasmid DNA by a metal-catalyzed oxidation (MCO) system composed of $Fe^{3+}$, $O_2$, and glutathione (GSH) as an electron donor was enhanced more effectively by the glycated CU,Zn-SOD than by the nonglycated enzyme. The capacity of glycated Cu,Zn-SOD to enhance damage to DNA was inhibited by diethylenetriaminepentaacetic acid (DETAPAC), azide, mannitol, and catalase. These results indicated that incubation of glycated CU,Zn-SOD with GSH-MCO may result in a release of $Cu^{2+}$ from the enzyme. The released $Cu^{2+}$ then likely participated in a Fenton-type reaction to produce hydroxyl radicals, which may cause the enhancement of DNA damage.
Park, Jeen-Woo,An, Soo Mi,Lee, Mi Hye,Kim, Kang Hwa,Kim, Il Han,Huh, Keun 영남대학교 약품개발연구소 1994 영남대학교 약품개발연구소 연구업적집 Vol.4 No.-
It has been proposed that oxygen-derived free radicals are produced upon reperfusion of ischemic brain, and that they can cause tissue injury to the brain. Global ischemia/reperfusion insult to gerbil brain was produced by transient occulsion and release of both common carotid arteries. Oxidative DNA damge, as measured by the 8-hydroxy-2'-deoxyguanosine (8-OH-dG) level, was increased by ischemia/reperfusion insult. Ichemia/reperfusion insult to gerbil brain did not cause any significant induction of antioxidant enzymes, such as superoxide dismutase, catalase, or a thiol-dependent protector protein. However, catalase activity was slightly decreased. These results suggest that ischemia/reperfusion insult to gerbil brain causes the DNA damage via the production of reactive oxygen species and that the antioxidant enzyme systems were not induced to prevent oxidative damage to DNA.
Nucleotide Binding Component of the Respiratory Burst Oxidase of Human Neutrophils
Park, Jeen-Woo,Ahn, Soo-Mi Korean Society for Biochemistry and Molecular Biol 1995 Journal of biochemistry and molecular biology Vol.28 No.3
The respiratory burst oxidase of neutrophils is a multicomponent enzyme, domant in resting cells, that catalyzes the reduction of oxygen to $O_{2}^{-}$ at the expense of NADPH. In the resting neutrophil, some of the components of the oxidase, including proteins p47 and p67, are in the cytosol, while the rest are in the plasma membrane. Recent evidence has suggested that at least some of the cytosolic oxidase components exist as a complex. The cytosolic complex with a molecular weight of ~240 kDa was found to bind to blue-agarose and 2',5'-ADP-agarose, which recognize nucleotide requiring enzymes. In order to identify the nucleotide binding component of the cytosolic complex we purified recombinant p47 and p67 fusion proteins using the pGEX system. Pure recombinant p47 was retained completely on 2',5'-ADP-agarose, whereas pure recombinant p67 did not bind to these affinity beads. On the basis of these results, we infer that p47 may contain the nucleotide binding site.
An Unusually Stable S-Nitrosothiol from Glutathione
Park, Jeen-Woo,Means, Gary-E. The Pharmaceutical Society of Korea 1989 Archives of Pharmacal Research Vol.12 No.4
Glutathione was converted by $HNO_2$ into a S-nitrosothiol which was stable in solution and atypically so even as a solid. FAB/MS and IR data have been obtained for the confirmation of structure of S-nitrosogulathione in the crystalline state.
Park, Jeen-Woo,Ahn, Soo-Mi,Kim, Eun-Ju,Lee, Soo-Min Korean Society for Biochemistry and Molecular Biol 1996 Journal of biochemistry and molecular biology Vol.29 No.6
A soluble protein from Saccharomyces cerevisiae specifically provides protection against a thiolcontaining oxidation system but not against an oxidation system without thiol. This 25-kDa protein was thus named thiol-dependent protector protein (TPP). The role of TPP in the cellular defense against oxidative stress was investigated in Escherichia coli containing an expression vector with a yeast genomic DNA fragment that encodes TPP (strain YP) and a mutant in which the catalytically essential amino acid in the active site of TPP (Cys-47) has been replaced with alanine by site-directed mutagenesis (strain YPC47A). There was a distinct difference between these two strains in regard to viability, modulation of activities of superoxide dismutase and catalase, and the oxidative damage of DNA upon exposure to menadione. These results suggest that TPP may play a direct role in the cellular defense against oxidative stress by functioning as an antioxidant protein.
Park, Jeen Woo,Ahn, Soo Mi 경북대학교 유전공학연구소 1995 遺傳工學硏究所報 Vol.10 No.1
Activation of superoxide-generating NADPH oxidase system of human neutrophils involves phosphorylation-dependent translocation of p47 to the plasma membrane. In contrast to the stimulation of the NADPH oxidase in intact cells. however. the activation of cell-free system requires the addition of anionic amphiphiles such as sodium dodecyl sulfate (SDS) or arachidonate. In this system, translocation of p47 is also an essential step for activation. but phosphorylation is not required. The basis of this difference in oxidase activation is not yet clear. We now report that in a cell-free oxidase system, phosphorylated recombinant p47 can be translocated in the absence of SDS or arachidonate. These findings suggest that both phosphorylation and anionic amphiphiles could cause a common change in conformation or charge of p47 that may result in the association of p47 with the plasma membrane.
Park, Jeen-Woo,Park, Hee-Sae Korean Society for Biochemistry and Molecular Biol 1998 Journal of biochemistry and molecular biology Vol.31 No.3
The leukocyte NADPH oxidase of neutrophils is a membrane-bound enzyme that catalyzes the production of $O_2^-$ from oxygen using NADPH as an electron donor. Dormant in resting neutrophils, the enzyme acquires catalytic activity when the cells are exposed to appropriate stimuli. During activation, the cytosolic oxidase components $p47^{phox}$ and $p67^{phox}$ migrate to the plasma membrane, where they associate with cytochrome $b_{558}$, a membrane-bound flavohemoprotein, to assemble the active oxidase. The oxidase can be activated in a cell-free system; the activating agent usually employed is an anionic amphiphile such as sodium dodecyl sulfate (SDS). Because $p47^{phox}$ can translocate by itself during activation, the conformational change in $p47^{phox}$ may be responsible for the activation of NADPH oxidase. We show here that the treatment of $p47^{phox}$ with SDS leads to an increase in the reactivity of the sutbydryl group of cysteines toward N-ethylmaleimide, indicating that the conformational change occurs when $p47^{phox}$ is exposed to SDS. We propose that this change in conformation results in the appearance of a binding site through which $p47^{phox}$ interacts with cytochrome $b_{558}$during the activation process.
Direct analysis of nicotelline from tobacco by MS with DADI/MIKE spectrometry
Park, Jeen-Woo The Pharmaceutical Society of Korea 1982 Archives of Pharmacal Research Vol.5 No.1
Nicotelline was directly analyzed from the crude tobacco extract by metastable studies. The metastable transitions of nicotelline were investigated by MS with DADI/MIKE spectrometry.
S-Nitrosylation of Sulfhydryl Groups in Albumin by Nitrosating Agents
Park, Jeen-Woo The Pharmaceutical Society of Korea 1993 Archives of Pharmacal Research Vol.16 No.1
The reaction of sulfhydryl groups in human serum ablumin with bacteriostatic and hypotensive notrosating agents such as sodium nitorprusside and sodium nitrite has been examined. The low reactivity of sodium nitroprusside to sulfhydral groups in albumin has been observed and the sterical inaccessilibility of the agent site which sulfhydryl group resides was implicated. The reaction of sodium nitrite with albumin was highly influenced by pH and little reactivity was observed at physiological pH. On the other hand, the reaction between albumin and S-nitrosoglutatione, an intermediate induced from the reaction of glutathione and nitrosating agents, resulted in the rapid decrease of free sulfhydryl groups in albumin. S-Nitrosylation of the sulfhydryl group by S-nitrosoglutathione and the subsequent production of mixed disulfide is the probable route of modification. In the physiological system, S-nitroso-glutathione may act as an active intermediate in expressing reacivity of nitrosating agents to sulfhydryl groups in albumin.