• Bulletin of the Korean Chemical Society
• /
• v.29 no.8
• /
• pp.1533-1538
• /
• 2008

Porphyrins generally bind DNA in two different ways with respect to the mixing ratio; monomeric binding at a low mixing ratio and outside stacking at a high mixing ratio. In the present study, CTDNA binding property of a planar structured porphyrin, 5,10,15,20-tetrakis(N-methyl-4-pyridin-4-yl-phenyl)porphyrin (referred to as B-TMPyP) was investigated using absorption, CD, LD, and $LD^r$ spectroscopies. B-TMPyP produced a bisignate CD band, even at the lowest mixing ratio, indicating that B-TMPyP may not have a monomeric binding mode. From the observations of the spectral changes to the absorption, CD, and LD spectra in mixing ratio dependent titrations, B-TMPyP seems to have a quite different stacking type compared to that for the binding of $H_2$TMPyP. Moreover, B-TMPyP produced a CD band of opposite shape in the Soret band region. A qualitative explanation for the observed optical differences is also given.

• Journal of the Korean Magnetic Resonance Society
• /
• v.20 no.2
• /
• pp.36-40
• /
• 2016

MRA1997 is a highly conserved protein from mycobacterial strains. However, no structural and functional information is associated with it. Thus, to obtain details about structure and function of this protein, we have utilized NMR spectroscopy. The recombinant MRA1997 was highly purified and its DNA binding mode was characterized. The tertiary structure of MRA1997 was modeled on the basis of our NMR chemical shift data combined with the webserver CS23D. The binding of MRA1997 with DNA was first monitored by electrophoresis mobility shift assays. The residues involved in DNA binding are identified using NMR chemical shift perturbation experiments. Based on our study, we suggest that MRA1997 interacts with DNA and may play an important role in Mycobacterium tuberculosis physiology.

• Journal of Life Science
• /
• v.10 no.4
• /
• pp.374-379
• /
• 2000

This study was attempted to evaluate an agonistic activity to benzodiazepine receptor of several medicinal pants, which have been used as sedatives in oriental medicine. The activities of the methanol extracts of composite preparation of oriental drugs were compared with those of the simple drugs, furthermore, the active fraction was found out from the simple preparation. Inhibitory effects of composite preparations, Cyperus rotundus/Acorus gramineus, Thuja orientalis/Euphoria longan, Thuja orientalis/Albizzia julibrissin, on the binding of ${[^3H]}$Ro15-1788, a selective benszodiazepine receptor antagonist to benzodiazepine receptor of rat cortices, were observed to be lower than those of corresponding simple preparations. These unexpected results suggest that some components of the composite druge may rather act as an obstacle, not to show the sinergistic effect. The methanol extracts of Cyperus rotundus having the highest activity were fractionated using polar and nonpolar solvents to give ethylacetate and hexane fractions, respectively. The ethylacetate fraction containing relatively polar components exhibited much higher activity than the hexane fraction, which consiste of nonpolar agonist, binding to benzodiazepine receptor. However, in the presence of GABA, this fraction inhibited ${[^3H]}$flunitrazepan binding, and these positive GABA shift supported the strong possibility of agonistic activity to benzodiazepine receptro. As a result, it may be concluded that the substance or substances with neurochemical properties as a benzodiazepine receptor agonist may contribute to the sedative property of Cyperus rotundus.

• BMB Reports
• /
• v.41 no.8
• /
• pp.575-580
• /
• 2008

Thymocyte-specific transcriptional regulatory systems can be used to better understand the relationship between transcription and V(D)J recombination during early T cell development. In this study, we generated transgenic mice expressing the transactivator Gal4-VP16 or the Gal4 DNA binding domain (Gal4-DBD) under the control of the lck proximal promoter, which is only active in immature thymocytes. From these studies Gal4-VP16 and Gal4-DBD expression was shown to significantly alter thymic cellularity and differentiation without significantly changing the $CD3^+$ thymocyte distribution. Furthermore, the presence of Gal4-VP16 or Gal4-DBD in the transgenic thymocytes retarded the mobility of the Gal4 DNA binding motif as determined by a gel mobility shift assay, suggesting that the developmental alteration did not affect the functional property of the transgenic proteins. These results indicated that lck promoter-driven Gal4-VP16 or Gal4-DBD expression did not affect $CD3^+$ mature thymocytes, thus this system can be applied to study transcriptional regulation of transresponder genes in bigenic mouse model thymocytes.

• Textile Coloration and Finishing
• /
• v.26 no.1
• /
• pp.32-38
• /
• 2014

There has been increasing demand to the eco-friendly materials such as phytoncide which is extracted to plants in the textile industry, recently. It is interesting that alginic acid sodium salt(Alg-Na) is used to eco-friendly binder for the functional capsule finishing. In this study, we made PEO/Alg-Na blend solutions of various ratio and observed the changing binding property of the blend solutions according to PEO contents through FT-IR, DSC, contact angle, peel strength, etc. The viscosity of Alg-Na/PEO blend solutions increased with increase of contents and the viscosity quickly increased with increase of PEO content in Alg-Na 5% content, specially. It is shown that the hydrogen bond peak by blend of Alg-Na and PEO found through FT-IR analysis but the peak decreased in PEO above 60% content. And the peel strength was predominant in PEO 50% ratio.

• Genomics & Informatics
• /
• v.19 no.1
• /
• pp.7.1-7.13
• /
• 2021

Levodopa (L-DOPA) therapy is normally practised to treat motor pattern associated with Parkinson disease (PD). Additionally, several inhibitory drugs such as Entacapone and Opicapone are also cosupplemented to protect peripheral inactivation of exogenous L-DOPA (~80%) that occurs due to metabolic activity of the enzyme catechol-O-methyltransferase (COMT). Although, both Entacapone and Opicapone have U.S. Food and Drug Administration approval but regular use of these drugs is associated with high risk of side effects. Thus, authors have focused on in silico discovery of phytochemicals and evaluation of their effectiveness against human soluble COMT using virtual screening, molecular docking, drug-like property prediction, generation of pharmacophoric property, and molecular dynamics simulation. Overall, study proposed, nine phytochemicals (withaphysalin D, withaphysalin N, withaferin A, withacnistin, withaphysalin C, withaphysalin O, withanolide B, withasomnine, and withaphysalin F) of plant Withania somnifera have strong binding efficiency against human COMT in comparison to both of the drugs i.e., Opicapone and Entacapone, thus may be used as putative bioenhancer in L-DOPA therapy. The present study needs further experimental validation to be used as an adjuvant in PD treatment.

• Biomolecules & Therapeutics
• /
• v.5 no.4
• /
• pp.325-330
• /
• 1997

Methanol extract of G. elata inhibited the binding of [/sup 3/H]Rol5-1788, a selective benzodiazepine receptor antagonest, to benzodiazepine receptor of rat cortices. Saturation experiments followed by Scatchard analysis of the results showed that the inhibition of [sub 3/H]Ro15-1788 binding by G. dlata. appeared to be com-petitive. These competitive inhibiton of the butanol fraction was observed to be higher than the methanol extract. Methanol extract of G. efara inhibited a [sub 3/H]flunitrazepam, a selective benzodiazepine receptor agonist, binding to benzodiazepine receptor. GABA significantly enhanced the inhibition of [/sub 3/H]flunitrazepam binding by G. elata, and these "positive GABA shift" supported the strong possibility of agonestic activity to benzodiazepine receptor Butanol fraction was observed to be higher than crude extract by methanol in an agonistic activity to benzodiazepine receptor, furthermore enhanced the binding of [sub 3/H]SR95531 to GABA receptor. Butanol fraction of G. elata significantly diminished the pentylenetetrazole-induced lethality of mice. From these results, it can be concluded that substance or substances with neurochemical properties characteri- stic of a benzodiazepine receptor agonist may be important components, and contribute to the anticonvulsant property of G. elata.

• Molecules and Cells
• /
• v.38 no.7
• /
• pp.657-662
• /
• 2015

Rapid and efficient engulfment of apoptotic cells is an essential property of phagocytes for removal of the large number of apoptotic cells generated in multicellular organisms. To achieve this, phagocytes need to be able to continuously uptake apoptotic cells. It was recently reported that uncoupling protein 2 (Ucp2) promotes engulfment of apoptotic cells by increasing the phagocytic capacity, thereby allowing cells to continuously ingest apoptotic cells. However, the functions of Ucp2, beyond its possible role in dissipating the mitochondrial membrane potential, that contribute to elevation of the phagocytic capacity have not been determined. Here, we report that the anion transfer or nucleotide binding activity of Ucp2, as well as its dissipation of the mitochondrial membrane potential, is necessary for Ucp2-mediated engulfment of apoptotic cells. To study these properties, we generated Ucp2 mutations that affected three different functions of Ucp2, namely, dissipation of the mitochondrial membrane potential, transfer of anions, and binding of purine nucleotides. Mutations of Ucp2 that affected the proton leak did not enhance the engulfment of apoptotic cells. Although anion transfer and nucleotide binding mutations did not affect the mitochondrial membrane potential, they exerted a dominant-negative effect on Ucp2-mediated engulfment. Furthermore, none of our Ucp2 mutations increased the phagocytic capacity. We conclude that dissipation of the proton gradient by Ucp2 is not the only determinant of the phagocytic capacity and that anion transfer or nucleotide binding by Ucp2 is also essential for Ucp2-mediated engulfment of apoptotic cells.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
• /
• 2002.05a
• /
• pp.215-215
• /
• 2002

Catalytic subunit of pyruvate dehydrogenase phosphatase (PDPc) has been suggested to have three major funational domains such as dihydrplipoamide adetyltransferase(E2)-binding domain, regulatory subunit of PDP(PDP)r-binding domain, and calcium-binding domain. In order to identify functional domains, recombinant catalytic subunit of pyruvate dehydrogenase phosphatase(rPDPc) was expressed in E. coli JM101 and purified to near homogeneity using the unique property of PDPc: PDPc binds to the inner lipoyl domain (L2) of E2 of ppyruvate dehydrogenase complex (PDC) in the presence of Ca+2, not under EGTA. PDPc was limited-proteolysed by typsin, chymotypsin, Arg-C, and elastase at pH 7.0 and 30C and N-terminal analysis of the fragments was done. Chymotrypsin, trypsin, and elastase made two major fragments: N-terminal large fragment, approx. 50kD and C-terminal small fragment, approx.10 kDa. Arg-C made three major fragments: N-terminal fragment, approx. 35kD, and central fragment, approx. 15 kD, and C-terminal fragment, approx. 10 kD. This study strongly suggest that PDPc consists of three major functional domains. However, further study should be necessary to identify the functional role.

• Korean Journal of Pharmacognosy
• /
• v.30 no.2
• /
• pp.211-215
• /
• 1999

This study was aimed to evaluate an agonistic activity to benzodiazepine receptor of several medicinal plants, which have been used as sedatives in oriental medicine. Methanol extracts of medicinal plants which were used in this study inhibited the binding of $[^3H]Ro15-1788$, a selective benzodiazepine receptor antagonist to benzodiazepine receptor of rat cortices. Inhibitory activity of Cyperus rotundus was observed to be the highest among the tested medicinal plants. Methanol extracts of Cyperus rotundus and Zizypus jujuba inhibited a $[^3H]flunitrazepam$, a selective benzodiazepine receptor agonist, binding to benzodiazepine receptor. GABA significantly enhanced the inhibition of $[3H]flunitrazepam$ binding by Cyperus rotundus and Zizypus jujuba, and these positive GABA shifts supported the strong possibility of agonistic activity to benzodiazepine receptor. From these results, it may be concluded that the substance or substances with neurochemical properties characteristic of a benzodiazepine receptor agonist may be important components and contribute to the sedative property of these medicinal plants.