• Korean Chemical Engineering Research
• /
• 제54권3호
• /
• pp.380-386
• /
• 2016

본 연구에서는 인플루엔자 바이러스 표면에 존재하는 neuraminidase 효소의 활성을 평가 할 수있는 종이칩 기반의 분석 시스템을 구축하였다. 종이칩의 장점을 살려 분석 전문가와 장비 없이 현장 진단(Point-of-care)이 가능하도록 X-Neu5Ac 기질을 이용한 비색분석법을 통해 시료 내 neuraminidase 효소의 존재를 정량적으로 확인 할 수 있도록 설계 및 제작하였다. Neuraminidase 효소의 활성을 확인할 수 있는 종이칩 센서(Paper-based neuraminidase assay sensor; PNAS) 성능 실험 결과 neuraminidase를 0.004 U/mL 농도부터 검출 가능하였으며, 인간 혈청에 각기 다른 농도로 존재하는 neuraminidase 효소의 양을 활성 평가를 통해 정량적으로 검출할 수 있음을 입증하였다($R^2$ > 0.99). 또한, 보관기간에 따른 종이칩의 안정성 평가 결과 빛이 차단 된 $4^{\circ}C$ 환경에서 보관 시 70일까지 초기 성능이 안정하게 유지됨을 확인하였다. 마지막으로, PNAS 상에서 효소 반응의 신뢰성 평가를 위해 미카엘리스-멘텐 동역학 (Michaelis-Menten kinetics)을 적용하여 X-Neu5Ac 기질에 대한 neuraminidase의 동역학 분석 결과 $K_m$ 값은 $8.327{\times}10^{-3}M$으로 확인되었으며, 이 값은 용액상에서의 효소 반응 속도 계산으로부터 산출된 값과($K_m=8.327{\times}10^{-3}M$) 근사한 수치임을 확인하였다. 본 연구로부터 개발된 종이칩 기반의 neuraminidase 효소 활성 평가 시스템은 인플루엔자 바이러스의 신속하고 안전한 검출에 다양하게 응용 될 수 있을 것으로 생각된다.

• BMB Reports
• /
• 제30권6호
• /
• pp.385-389
• /
• 1997

Many cell types are known to stimulate $CD8^+$ T cells in allogeneic recognition such as mixed lymphocyte reaction (MLR). Whereas dendritic cells are most potent among them. T cells are usually considered very poor in stimulating $CD8^+$ T cells although there are some tumor cells that are weakly stimulatory. T cells, as a stimulator, cultured in the presence of concanavalin A that were otherwise nonstimulatory to $CD8^+$ T cells appeared to stimulate $CD8^+$ T cells strongly when they were pretreated with neuraminidase. The enhancement of MLR by neuraminidase could be achieved by treating either the stimulators or responders with neuraminidase. Removal of negatively-charged sialic acid moieties from the cell surface, which reduced electrostatic repulsion between responders and stimulators to give better cell-cell contact might be responsible for the enhanced MLR. In addition, neuraminidase treatment also appeared to deliver activation signal to responding T cells since it could activate $CD8^+$ T cells in synergy with phorbol myristate acetate. The maximal responses were observed when both responders and stimulators were treated with neuraminidase.

• 통합자연과학논문집
• /
• 제8권3호
• /
• pp.209-213
• /
• 2015

Influenza A virus (H1N1) causes and spreads infectious diseases and becomes a major health threat in humans. Among the subtypes of influenza virus, neuraminidase (NA) plays an important role in viral life cycle and becomes an attractive therapeutic target. Currently two NA inhibitors namely Zanamivir and Oseltamivir are available for treating infectious diseases. Recently five naturally derived polyphenols extracted from Phellinus baumii was reported as inhibitors against NA. Molecular docking is powerful tool in computer aided drug designing which aids in exploring and elucidating the properties of the molecules from their 3D structure. Hence, in the present study, molecular docking was carried out on reported polyphenols isolated from ethanolic extract of fruiting bodies of Phellinus baumii. The objective of this work was to study the interaction and to propose the binding mode of these compounds within the binding site of H1N1 neuraminidase. The results showed these compounds had better binding energy and H-bond interactions with the important active site residues of the receptor which authenticate these compounds contributes to inhibitory activity of neuraminidase to treat influenza infection.

• Mycobiology
• /
• 제42권2호
• /
• pp.189-192
• /
• 2014

During a search for neuraminidase inhibitors derived from medicinal fungi, we found that the fermentation broth of Phellinus linteus exhibited potent neuraminidase inhibitory activity. Through bioassay-guided fractionation, two active compounds were purified from the ethyl acetate-soluble portion of the fermentation broth of P. linteus. These structures were identified as inotilone (1) and 4-(3,4-dihydroxyphenyl)-3-buten-2-one (2) by spectroscopic methods. Compounds 1 and 2 inhibited H1N1 neuraminidase activity with $IC_{50}$ values of 29.1 and 125.6 $125.6{\mu}M$, respectively, in a dose-dependent manner. They also exhibited an antiviral effect in a viral cytopathic effect reduction assay using MDCK cells. These results suggest that compounds 1 and 2 from the culture broth of P. linteus would be good candidates for the prevention and therapeutic strategies towards viral infections.

• 한국가금학회지
• /
• 제10권1호
• /
• pp.60-66
• /
• 1983

Monoclonal antibodies against Taka virus, a variant of Newcastle disease virus (NDV), were produced to compare the antigenicites of several avian paramyxoviruses including NDV. It was also used to study the activesite(s) of haemagglutin (HA) and neuraminidase activities of NDV. Five independent hybrid cell lines, which produced monoclonal antibodies against haemagglutinin-neuraminidase (HN) molecule of Taka virus, were established. From the results of the cross haemagglutination-inhibition(HI) test the monoclonal antibodies, the HN molecule of Taka virus seemed to have at least three different antigenic determinats; one was specific for all NDV strain tested, the second was only for Taka virus and the third was for Take virus, Banger and Yucaipa Furthermore the differences in the ratio of HI to neuraminidase-inhibition titers suggested that the active sites involved in HA and neuraminidase activities might be different from each other. However, since each of five monoclonal anitbodies was not especially specific for either HA or neuraminidase, the possibility that a single active site on the HN molecule may be responsible for both activities has not been excluded.

• Mycobiology
• /
• 제40권2호
• /
• pp.142-144
• /
• 2012

During the search for neuraminidase inhibitors from medicinal fungi, we found that the culture broth of Phellinus linteus exhibited potent inhibitory activity. Solvent partition, Sephadex LH-20 column chromatography, and high-performance liquid chromatography (HPLC) were performed for purification of two active substances from the culture broth. According to $^1H$ NMR measurements and comparison of HPLC retention times with those of authentic compounds, their chemical structures were identified as hispidin and hypholomine B. Compounds (hispidin) 1 and 2 (hypholomine B) inhibited neuraminidase, with $IC_{50}$ values of 13.1 and 0.03 ${\mu}M$, respectively.

• EDISON SW 활용 경진대회 논문집
• /
• 제4회(2015년)
• /
• pp.212-216
• /
• 2015

Oseltamivir, also known as Tamifu, is an inhibitor of neuraminidase protein which plays an essential role in proliferation and replication of influenza virus. Binding to the active site of neuraminidase, the oseltamivir prevents the protein from enzyme reaction. Conformational change of the protein(neuraminidase) should be accompanied by the enzyme reaction, but the drug inhibits the protein to deform. In this study, we examine the influence of oseltamivir on protein's conformational change in the structural and mechanical point of view. Finite element analysis of the protein can be an useful approach to investigate the influence of oseltamivir on the deformation of a protein. We suggest the finite element based protein model, and then perform the linear static analysis with the displacement loading condition based on the first two largest motion which can be obtained from the normal mode analysis. The results show that it takes more energy to change shape of the protein with an oseltamivir attached than the protein without an oseltamivir.

• Bulletin of the Korean Chemical Society
• /
• 제29권11호
• /
• pp.2221-2226
• /
• 2008

• Journal of Microbiology and Biotechnology
• /
• 제13권5호
• /
• pp.778-782
• /
• 2003

In the course of screening anti-influenza agents from natural products, four neuraminidase inhibitors were isolated from the methanol extract of mushroom Microphorus affinis by purification using solvent partition, silica gel column chromatography, Sephadex LH-20, and semi-preparative HPLC. The chemical structures of these compounds were identified as ${\alpha}-lupeol$, methyl linoleate, methyl palmitate, and methyl oleate by means of spectral data including GC-MS, $^1H-,\;and\;^{13}C-NMR\;with\;IC_{50}$ values of 5.65, 7.07, 7.12, and $7.52\;\mu\textrm{M}$, respectively. They did not inhibit other glycosidases such as glucosidase, mannosidase, and galactosidase, indicating that they were relatively specific inhibitors of neuraminidase. The relationship between the fatty acid structure and inhibitory activity was investigated. The result showed that, in the case of an aliphatic linear hydrocarbon skeleton, at least one carboxyl (presumably any carbonyl) moiety and sixteen carbons were the necessary requirements for potent inhibition, whereas saturated, unsaturated, free, and ester forms did not have any significant effect on the activity.

• Archives of Pharmacal Research
• /
• 제26권5호
• /
• pp.367-374
• /
• 2003

In the course of screening neuraminidase inhibitors from herbal medicines, Reynoutria elliptica exhibited high inhibitory activity. Four active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification using sillica gel, Sephadex LH-20 chromatography, and recrystallization. The chemical structures of these compounds were identified as 1,3,8-trihydroxy-6-methylanthraquinone (emodin) 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (emodin 3-methyl ether; physcion), 1,3,8-trihydroxy-6-hydoxymethylanthraquinone ($\omega$-hydroxyemodin), and 3,5,4 -trihydroxystilbene (trans-resvertrol) by spectral data including MS, $^1 H-, and ^{13}C-NMR. The IC_{50}$ values of emodin, emodin 3-methyl ether, $\omega$-hydroxyemodin, and trans-resvertrol were 2.81, 74.07, 10.49, and 8.77 $\mu$M, respectively. They did not inhibit other glycosidase such as glucosidase, mannosidase, and galactosidase, indicating that they were relatively specific inhibitors of neuraminidase.