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MODULATION Of THE MUTAGENIC EffECTS Of 2-AMINO-3-METHYLIMIDAZO[4,5-f]QUINOLINE (IQ) AND 2-AMINO-3,4-DIMETHYLIMIDAZO[4,5-f]QUINOLINE (MEIQ) IN BACTERIA WITH RAT-LIVER 9000 X G SUPERNATANT OR MONOLAYERS Of RAT HEPATOCYTES AS AN ACTIVATION SYSTEM

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MUTATION RESEARCH 1988年第1期197卷 39-49页

作者： HOLME, JA BRUNBORG, G ALEXANDER, J TRYGG, B BJORNSTAD, C NATL INST PUBL HLTH DEPT TOXICOL GEITMYRSVEIEN 75 N-0462 OSLO 4 NORWAY

An in vitro protocol was designed to separate the process of metabolic activation from the mutational events. Cultured rat hepatocytes were first incubated with the foood mutagens 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) or 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ). After the incubation period the medium was removed and further incubated with Salmonella typhimurium TA98. A high direct mutagenic activity of the culture medium was then measured. The half-lives of the mutagenic metabolites formed form IQ and MeIQ were in the order of 45 min. The presence of the cytochrome P450 inhibitors .alpha.-naphthoflavone and metyrapone during the pre-incubation period reduced the accumulation of mutagenic metabolites. No effects of ascorbate on the mutagenic effects of IQ and MeIQ were seen. (+)-Catechin, another antioxidant and free-radical scavenger, markedly enhanced the number of IQ/MeIQ-induced revertants when added to the hepatocytes. In contrast, (+)-catechin clearly decreased the number of revertants when 9000 .times. g supernatant from rat liver (s9) was used as an activation system. No marked effect of pentachlorophenol, an inhibitor of hepatocyte sulfation and bacterial O-acetylation, was seen using hepatocytes as an activation system, while the mutagenic activity of both IQ and MeIQ was reduced by 90% in the S9/Salmonella system. The addition of an inhibitor of glucuronidation, galactosamine, or the nucleophile glutathine caused no or only minor decrease in the genotoxic effects of the IQ compounds. With both S9 and hepatocytes as activation systems the relative mutagenic effects observed in the S. typhimurium strains TA98 and TA98 NR were in the same order of magnitude, while a large decrease was seen with TA98/1,8-DNP6. The results show that this in vitro test protocol may be useful as a tool to study mechanisms involved in the formation of mutagenic metabolites.

关键词： Mutagenic activation Heterocyclic aromatic amines Hepatocytes Carcinogens Mutagens IQ MeIQ Asc ascorbate ANf α-naphthoflavone CAT (+)-catechin DMSO dimethyl sufoxide 1,8-DNP 1,8-dinitropyrene GAL galactosamine GSH glutathione HAR harmine IQ 2-amino-3-metylimidazo[4,5- f ]quinoline MeIQ 2-amino-3,4-dimethylimidazo[4,5- f ]quinoline MET metyrapone S9 9000 × g supernatant from rat-liver homogenate UDPGA uridine diphosphoglucuronic acid

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DIffUSION-LIMITED COMPONENT Of MITOCHONDRIAL f1-ATPASE

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INTERNATIONAL JOURNAL Of BIOCHEMISTRY 1993年第5期25卷 701-706页

作者： BARACCA, A SOLAINI, G DINELLI, G CASTELLI, GP LENAZ, G UNIV PERFEZIONAMENTO S ANNA SCUOLA SUPER STUDII-56100 PISAITALY

1. The possibility that the rate of ATP hydrolysis by f1-ATPase approaches the diffusion-controlled limits was investigated by measuring the values of k(cat) and k1 (k(cat)/K(m)) as a function of increasing viscosity. 2. The values of k(cat)/K(m) decrease significantly with increasing viscosity;further such decrease was lower when f1-ATPase hydrolyzed poor substrate such as Ca- and Mg-ITP or when the hydrolysis rates were measured at temperatures below 20-degrees-C. 3. Viscosity also decreases k(cat), but only at high concentrations of viscosogenic agents. 4. These results suggest that ATP hydrolysis is at least partly diffusion-controlled, although a general non-specific perturbation in the enzyme structure is also effected by viscosity.

关键词： Cf 1 chloroplast coupling factor protein f 0 membrane sector part of H + -translocating ATP synthase of f 0 f 1 type f 1 f 1 -ATPase (catalytic part of H + -translocating ATP synthase of f 0 f 1 type). Enzymes: f 1 -ATPase (EC 3.6.1.3), pyruvate kinase (EC 2.7.1.40), lactic dehydrogenase (EC 1.1.1.27)

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A bibliometric analysis of preclinical trials of Andrographis paniculata (Burm.f.) Nees in diabetes mellitus

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SOUTH AfRICAN JOURNAL Of BOTANY 2022年第PartB期151卷 128-143页

作者： Arifah, fitriana Hayyu Nugroho, Agung Endro Rohman, Abdul Sujarwo, Wawan Univ Gadjah Mada Fac Pharm Yogyakarta 55281 Indonesia Univ Gadjah Mada Fac Pharm Dept Pharmacol Clin Pharm Yogyakarta 55281 Indonesia Univ Gadjah Mada Fac Pharm Dept Pharmaceut Chem Yogyakarta 55281 Indonesia Univ Gadjah Mada Inst Halal Ind & Syst PUI PT IHIS Ctr Excellence Yogyakarta 55281 Indonesia Natl Res & Innovat Agcy BRIN Ethnobiol Res Grp Res Ctr Biol Cibinong 16911 West Java Indonesia

The prevalence of diabetes mellitus has increased over time. Medicinal plants, including Andrographis panicu-lata (Burm.f) Nees, are recognized for their use to manage hyperglycemia. Nowadays, plenty of papers are published about A. paniculata as an antidiabetic;however, no bibliometric study about the topic exists. This study examines the existing papers about the preclinical trial of A. paniculata as an antidiabetic agent using bibliometric analysis focusing on countries, institutions, publishers, authors, documents, and keywords. Bib-liographic information of relevant research and conference articles were obtained from the Scopus database. In total, 97 articles published between 1994 and 2021 were selected, covering 376 authors and 1270 key-words. Data were analyzed bibliometrically using Vosviewer 1.6.16. A total of 97 published papers occurred from 1994 to 2021 were selected. India, Universitas Gadjah Mada (Indonesia), Journal of Ethnopharmacology, and Agung Endro Nugroho (Universitas Gadjah Mada, Indonesia) were the most productive country, institu-tion, publisher, and author, respectively. The analysis of the most influential papers, co-citation network of the most influential papers, bibliographical coupling network based on authors, and keyword co-occurrence network and overlay demonstrated that the abundance and variety of existing papers about preclinical trials of A. paniculata as an antidiabetic were from phytochemistry, pharmacology, and drug formulation. The find-ings of our analysis have implications for managerial and theoretical aspects on this topic, such as encourag-ing research collaborations by analyzing the contributions of countries, institutions, publishers, and authors and revealing research gaps (molecular mechanisms, toxicities and side effects, drug formulations, and clini-cal trials) to accept a phytomedicine as a therapeutic option.(c) 2021 SAAB. Published by Elsevier B.V. All rights reserved.

关键词： Andrographis paniculata (Burm f ) Nees Diabetes mellitus Bibliometric analysis Scopus Vosviewer

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PURIfICATION Of THE H+-ATPASE fROM RHODOBACTER-CAPSULATUS, IDENTIfICATION Of THE f1f0 COMPONENTS AND RECONSTITUTION Of THE ACTIVE ENZYME

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BIOCHIMICA ET BIOPHYSICA ACTA 1988年第2期934卷 227-234页

作者： GABELLINI, N GAO, Z ECKERSKORN, C LOTTSPEICH, f OESTERHELT, D Max-Planck-Institut für Biochemie Martinsried F.R.G.

A simple method has been adopted for the isolation of the H+-ATPase from cell membranes of Rhodobacter capsulatus that is based on octylglucoside solubilization. The highly purified f0f1 enzyme catalyzes ATP hydrolysis and DCCD-sensitive ATP-Pi exchange. The isolated complex consists of nine different polypeptides with apparent molecular masses of 50, 45, 34, 29, 23, 20, 18.5, 11 and 7.5 kDa. The N-terminal sequence of the eight largest subunits were determined by automated Edman degradation. The five f1 polypeptides could be readily identified by their homology to the f1 subunits .alpha., .beta., .gamma., .delta. and .epsilon. from other Rhodospirillaceae. In contrast to prokaryotic f0 complexes known today, the membrane portion of H+-ATPase from R. capsulatus was found to be composed of four polypeptides. Three of these correspond to subunit a, b and c of the Escherichia coli enzyme (29, 18.5 and 7.5 kDa). A fourth subunit of 23 kDa may be also related to subunit b. The ATP-synthase of this photosynthetic bacterium is in this respect similar to that of chloroplasts.

关键词： ATPase purification, H + - f 0 f 1 Enzyme reconstitution ( Rb. capsulatus ) SDS-PAGE sodium dodecyl sulfate polyacrylamide gel electrophoresis DCCD N , N ′-dicyclohexylcarbodiimide fCCP carbonylcyanide p -(trifluoromethoxy)-phenylhydrazone octylglucoside n -octyl-β-D-glucopyranoside Triton X-100 octylphenoxypoly(ethoxyethanol) Tricine N -[2-hydroxy-1,1-(bis(methyl)ethyl]glycine DTT dithiothreitol EDTA ethylene dinitrile tetra acetic acid HPLC high performance liquid chromatography P i inorganic phosphate

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BETA-SUBUNIT Of ESCHERICHIA-COLI f1-ATPASE - AN AMINO-ACID REPLACEMENT WITHIN A CONSERVED SEQUENCE (G-X-X-X-X-G-K-T/S) Of NUCLEOTIDE-BINDING PROTEINS

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fEBS LETTERS 1987年第2期218卷 222-226页

作者： HSU, SY NOUMI, T TAKEYAMA, M MAEDA, M ISHIBASHI, S fUTAI, M OSAKA UNIV INST SCI & IND RESDEPT ORGAN CHEM & BIOCHEMIBARAKIOSAKA 567JAPAN

A mutant strain Kf87 of E. coli with a defective beta-subunit (Ala-151----Val) of f1-ATPase was isolated. The mutation is within the conserved sequence (G-X-X-X-X-G-K-T/S) of nucleotide-binding proteins. The mutant f1-ATPase had a much higher rate of uni-site hydrolysis of ATP than the wild type, and about 6% of the wild-type multi-site activity. The mutant enzyme showed defective transmission of conformational change(s) between the ligand- and aurovertin-binding sites.

关键词： f 1 -ATPase Nucleotide-binding protein Uni-site catalysis Oncogene

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IMMUNOLOGICALLY CROSS-REACTIVE AND REDOX-COMPETENT CYTOCHROME B6/f-COMPLEXES IN THE CHLOROPHYLL-fREE PLASMA-MEMBRANE Of CYANOBACTERIA

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fEBS LETTERS 1990年第1-2期273卷 227-231页

作者： KRAUSHAAR, H HAGER, S WASTYN, M PESCHEK, GA Biophysical Chemistry Group Institute of Physical Chemistry University of Vienna Währingerstraβe 42 A-1090 Vienna Austria

Plasma and thylakoid membranes were separated and purified from cell-free extracts of the cyanobacteria Anacystis nidulans, Synechocystis 6714, Anabaena variabilis and Nostoc sp. strain Mac. Immunoblots of the membrane proteins using antisera raised against subunits I–IV of the chloroplast b 6 / f -complex gave evidence for the presence of a homologous complex in both plasma and thylakoid membranes from the four species of cyanobacteria investigated. Both plasma and thylakoid membranes catalyzed the electron transfer from (exogenous) plastoquinol-9 and NADH to horse heart ferricytochrome c . However, while with plasma membranes these reactions were severely inhibited by low concentrations of antimycin A and rotenone, respectively, the inhibitors were without major effect on thylakoid membranes. The results will be discussed in terms of a possible similarity (analogy and/or homology?) of cyanobacterial plasma membranes to the inner mitochondrial membrane.

关键词： Respiratory chain Cytochrome b 6 / f -complex Cytochrome- c reductase Inhibitor Plasma membrane Thylakoid membrane Cyanobacteria CM cytoplasmic (plasma) membrane ICM in-tracytoplasmic (thylakoid) membrane PCC Pasteur Culture Collection, Paris, france ATCC American Type Culture Collection cyt cytochrome SDS-PAGE sodium dodecylsulfate polyacrylamide gel electrophoresis

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Reinvestigation of carvotanacetone after 100years along with minor terpenoid constituents of Blumea malcolmii Hook. f. essential oil

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NATURAL PRODUCT RESEARCH 2016年第20期30卷 2368-2371页

作者： Joshi, Rajesh K. Pai, Sandeep R. Indian Council Med Res Dept Phytochem Reg Med Res Ctr Belgaum India Indian Council Med Res Plant Biotechnol & Tissue Culture Div Reg Med Res Ctr Belgaum India

Reinvestigation of essential oil constituents of Blumea malcolmii Hook. f. (Asteraceae) was carried out after 100years using gas chromatography equipped with flame ionisation detector (GC-fID) and gas chromatography coupled with mass spectrometry (GC/MS). Eighteen constituents, representing 99.2% of the total oil, were identified. The major compound was identified by GC/MS and NMR (H-1 and C-13) as carvotanacetone (92.1%). The minor compounds of essential oil have also been identified for the first time in B. malcolmii. The oil was found to be rich in oxygenated monoterpene-type constituents (95.0%). [GRAPHICS]

关键词： Blumea malcolmii Hook f Asteraceae carvotanacetone GC MS NMR (H-1 and C-13)

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fAST ELECTRON-TRANSfER fROM LOW-POTENTIAL TO HIGH-POTENTIAL CYTOCHROME-B6 IN ISOLATED CYTOCHROME-B6f COMPLEX

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fEBS LETTERS 1988年第1期232卷 204-208页

作者： NITSCHKE, W HAUSKA, G CROfTS, AR UNIV REGENSBURG INST BOTUNIV STR 31D-8400 REGENSBURGFED REP GER UNIV ILLINOIS DEPT PHYSIOL & BIOPHYSURBANAIL 61801

The two hemes of cytochrome b 6 in the cytochrome b 6 f complex isolated from chloroplasts exhibit slight spectral differences in the α-band at room temperature, sufficient to deconvolute redox kinetics of cytochrome b 6 into the contributions of the two components. The deconvoluted changes observed can be explained by fast electron transfer from low- to high-potential cytochrome b 6 .

关键词： Cytochrome b 6 f complex Cytochrome b Oxidant-induced reduction Q-cycle Spectral deconvolution PQH 2 , plastoquinol b h , high-potential cytochrome b b 1 , low-potential cytochrome b f , cytochrome f b 6 f , cytochrome b 6 f complex bc 1 , cytochrome bc 1 complex

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Combination of IL-17A/f and TNf-α uniquely alters the bronchial epithelial cell proteome to enhance proteins that augment neutrophil migration

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JOURNAL Of INfLAMMATION-LONDON 2022年第1期19卷 1-19页

作者： Altieri, Anthony Piyadasa, Hadeesha Hemshekhar, Mahadevappa Osawa, Natasha Recksiedler, Breann Spicer, Victor Hiemstra, Pieter S. Halayko, Andrew J. Mookherjee, Neeloffer Univ Manitoba Manitoba Ctr Prote & Syst Biol Dept Internal Med Winnipeg MB Canada Univ Manitoba Dept Immunol Winnipeg MB Canada Stanford Univ Sch Med Dept Pathol Palo Alto CA USA Leiden Univ Dept Pulmonol Med Ctr Leiden Netherlands Univ Manitoba Dept Physiol & Pathophysiol Winnipeg MB Canada Childrens Hosp Res Inst Manitoba Biol Breathing Grp Winnipeg MB Canada

Background: The heterodimer interleukin (IL)-17A/f is elevated in the lungs in chronic respiratory disease such as severe asthma, along with the pro-inflammatory cytokine tumor necrosis factor-alpha (TNf-alpha). Although IL-17A/f and TNf-alpha are known to functionally cooperate to exacerbate airway inflammation, proteins altered by their interaction in the lungs are not fully ***: We used Slow Off-rate Modified Aptamer-based proteomic array to identify proteins that are uniquely and/or synergistically enhanced by concurrent stimulation with IL-17A/f and TNf-alpha in human bronchial epithelial cells (HBEC). The abundance of 38 proteins was significantly enhanced by the combination of IL-17A/f and TNf-alpha, compared to either cytokine alone. four out of seven proteins that were increased > 2-fold were those that promote neutrophil migration;host defence peptides (HDP;Lipocalin-2 (LCN-2) and Elafin) and chemokines (IL-8, GRO alpha). We independently confirmed the synergistic increase of these four proteins by western blots and ELISA. We also functionally confirmed that factors secreted by HBEC stimulated with the combination of IL-17A/f and TNf-alpha uniquely enhances neutrophil migration. We further showed that PI3K and PKC pathways selectively control IL-17A/f + TNf-alpha-mediated synergistic production of HDPs LCN-2 and Elafin, but not chemokines IL-8 and GRO alpha. Using a murine model of airway inflammation, we demonstrated enhancement of IL-17A/f, TNf-alpha, LCN-2 and neutrophil chemokine KC in the lungs, thus corroborating our findings ***: This study identifies proteins and signaling mediated by concurrent IL-17A/f and TNf-alpha exposure in the lungs, relevant to respiratory diseases characterized by chronic inflammation, especially neutrophilic airway inflammation such as severe asthma.

关键词： IL-17A f TNf-alpha Inflammation Lung Host defence peptides Neutrophils

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CYTOCHROME-B6 fROM ISOLATED CYTOCHROME-B6f COMPLEXES - EVIDENCE fOR 2 SPECTRAL fORMS WITH DIffERENT MIDPOINT POTENTIALS

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fEBS LETTERS 1983年第2期153卷 413-419页

作者： HURT, EC HAUSKA, G Universität Regensburg Institut für Botanik D-8400 Regensburg FRG

Cytochrome b 6 from spinach chloroplasts (either within the purified cytochrome b 6 f complex, or in its isolated form) exhibits two spectral species, which correspond to two midpoint potentials. This can be demonstrated by low temperature difference spectroscopy at fixed redox potentials. The high potential form of cytochrome b 6 has a split α-peak at 557.5 and 561.5 nm, the low potential form has a symmetrical α-peak at 560.5 nm. Similar results were obtained with cytochrome b 6 in the isolated cytochrome b 6 f complex from the cyanobacterium Anabaena variabilis .

关键词： Cytochrome b 6 Cytochrome b 6 f complex Chloroplast electron transport Cyanobacteria Low temperature difference spectroscopy Redox potential MOPS 3-( N -morpholino)propanesulfonic acid MES 2-( N -morpholino)ethanesulfonic acid Tris Tris(hydroxymethyl) aminomethane

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