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111.
112.
Inhibition by ricin of protein synthesis in vitro: 60S ribosomal subunit as the target of the toxin (Short Communication) 总被引:1,自引:0,他引:1
Simonetta Sperti Lucio Montanaro Alessandro Mattioli Fiorenzo Stirpe 《The Biochemical journal》1973,136(3):813-815
Poly(U)-directed polyphenylalanine synthesis by rat liver ribosomes is strongly inhibited by ricin. Experiments involving hybridization between subunits derived from normal and ricin-treated ribosomes demonstrate that the 60S subunit is the site of action of the toxin. The toxin inactivates the 60S subunit independently of the presence of the 40S subunit. 相似文献
113.
Claude Crétin Naïma Bakrim Eliane Kéryer Simonetta Santi Loïc Lepiniec Jean Vidal Pierre Gadal 《Plant molecular biology》1991,17(1):83-88
Phosphoenolpyruvate carboxylase (PEPC)-deficient mutants ofEscherichia coli have been complemented with a plasmid bearing a full-length cDNA encoding the C4-type form ofSorghum leaf PEPC. Transformed cells grew on minimal medium. Two clones were selected which produce a functional and full-sized enzyme protein as determined by activity assays, immunochemical behavior and SDS-PAGE. In addition, regulatory phosphorylation of immunopurified recombinant PEPC was observed when the enzyme was incubated with a partially purified plant PEPC kinase. These results establish thatE. coli cells produce a genuine, phosphate-free, higher-plant PEPC. Application of immunoadsorbtion chromatography to bacterial extracts makes it possible to prepare highly pure protein available for biochemical studies. 相似文献
114.
Stefania D'Atri Maria Pia Fuggetta Gabriella Giganti Lucio Tentori Mario Roselli Corrado Nunziata Simonetta Pastore Enzo Bonmassar Liana De Vecchis 《Cancer immunology, immunotherapy : CII》1988,27(2):163-170
Summary A good correlation was found between in vivo and in vitro responses of peripheral MNC from breast cancer patients and the NK boosting effect of human IFN. In vitro immunochemotherapy studies showed that marked antitumor effects were obtained against cultured cancer cells when a widely used chemotherapeutic agent such as 5-FU was combined with nonsensitized spontaneously cytolytic MNC, preactivated in vitro with IFN. These results suggest that the in vitro susceptibility assay of MNC to IFNs could be used for predicting favorable responses to immunochemotherapy regimens employing IFNs as immunomodulating agents.
Abbreviations used: IFN, beta-interferon; CM, complete medium; CTX, cyclophosphamide; E:T ratio, effector target ratio; EDTA, ethylenediaminetetraacetic acid; FCS, fetal calf serum; 5-FU, 5-fluorouracil; IFN, gamma-interferon; Hepes, N-2-hydroxyethylpiperazine-N-2-ethanesulphonic acid IFNs, interferons; KC, killed cells; LDIF, low doses beta-interferon; LU, lytic unit; MAT macrotest; MIT, microtest; MNC, mononuclear cells; MNC/IFN, IFN-pretreated MNC; MTX, methotrexate; NB, no boosting; NK, natural killer; NKA, NK activity; NR, natural resistance; PM, positive modulation; SE, standard error; WM, washing medium 相似文献
115.
Troponin T switching in the developing rat heart 总被引:6,自引:0,他引:6
L Saggin S Ausoni L Gorza S Sartore S Schiaffino 《The Journal of biological chemistry》1988,263(34):18488-18492
A monoclonal antibody specific for cardiac troponin T has been used to investigate troponin changes during development in the rat heart. Specificity of the antibody was determined by immunoblot analysis with purified bovine cardiac troponin. In the rat heart, immunoblot analysis shows that anticardiac troponin T reacts with a 42.5-kDa band in fetal ventricles and with a 41-kDa band in adult ventricles. The faster migrating troponin T is present in traces in the fetal heart and increases markedly during the first 2 weeks after birth, concomitantly with the progressive decrease of the slower migrating form that is no longer detectable in the adult. The pattern of reactivity of the monoclonal antibody is not modified by alkaline phosphatase pretreatment, suggesting that the antibody is not specific for a phosphorylated epitope. Conditions known to affect cardiac myosin composition, such as hypothyroidism and hypertrophy secondary to systemic hypertension, do not change the troponin T isoform profile of adult rat ventricles. The expression and accumulation of the adult isoforms of troponin T are not suppressed by propylthiouracil treatment of pregnant and nursing rats. 相似文献
116.
Properties of D-amino-acid oxidase from Rhodotorula gracilis 总被引:2,自引:0,他引:2
M Pilone Simonetta L Pollegioni P Casalin B Curti S Ronchi 《European journal of biochemistry》1989,180(1):199-204
The flavoprotein D-amino-acid oxidase was purified to homogeneity from the yeast Rhodotorula gracilis by a highly reproducible procedure. The amino acid composition of the protein was determined; the protein monomer had a molecular mass of 39 kDa and contained one molecule of FAD. The ratio between A274/A455 was about 8.2. D-Amino-acid oxidase from yeast showed typical flavin spectral perturbations on binding of the competitive inhibitor benzoate and was reduced by D-alanine under anaerobiosis. The enzyme reacted readily with sulfite to form a covalent reversible adduct and stabilized the red anionic form of the flavin semiquinone on photoreduction in the presence of 5-deazariboflavin; the 3,4-dihydro-FAD form was not detectable after reduction with sodium borohydride. Thus D-amino-acid oxidase from yeast exhibited most of the general properties of the dehydrogenase/oxidase class of flavoproteins; at the same time, the enzyme showed some peculiar features with respect to the same protein from pig kidney. 相似文献
117.
Francesca Marcon Roberta Meschini Egidio Iorio Simonetta Palleschi Gabriele De Luca Ester Siniscalchi Luigi Conti Mattea Chirico Maria Elena Pisanu Francesca De Battistis Barbara Rossi Anna Minoprio Alessandro Giuliani Peter Karran Margherita Bignami 《Aging cell》2022,21(7)
hMTH1 protects against mutation during oxidative stress. It degrades 8‐oxodGTP to exclude potentially mutagenic oxidized guanine from DNA. hMTH1 expression is linked to ageing. Its downregulation in cultured cells accelerates RAS‐induced senescence, and its overexpression in hMTH1‐Tg mice extends lifespan. In this study, we analysed the effects of a brief (5 weeks) high‐fat diet challenge (HFD) in young (2 months old) and adult (7 months old) wild‐type (WT) and hMTH1‐Tg mice. We report that at 2 months, hMTH1 overexpression ameliorated HFD‐induced weight gain, changes in liver metabolism related to mitochondrial dysfunction and oxidative stress. It prevented DNA damage as quantified by a comet assay. At 7 months old, these HFD‐induced effects were less severe and hMTH1‐Tg and WT mice responded similarly. hMTH1 overexpression conferred lifelong protection against micronucleus induction, however. Since the canonical activity of hMTH1 is mutation prevention, we conclude that hMTH1 protects young mice against HFD by reducing genome instability during the early period of rapid growth and maximal gene expression. hMTH1 protection is redundant in the largely non‐growing, differentiated tissues of adult mice. In hMTH1‐Tg mice, expression of a less heavily mutated genome throughout life provides a plausible explanation for their extended longevity. 相似文献
118.
Carnicelli Domenica; Brigotti Maurizio; Alvergna Paola; Pallanca Alessandra; Sperti Simonetta; Montanaro Lucio 《Journal of experimental botany》1997,48(8):1519-1523
A large number of type 1 ribosome-inactivating proteins (RIPs)from plants (families of Caryophyllaceae, Cucurbitaceae, Euphorbiaceae,Phytolaccaceae, and Poaceae) were examined for their requirementfor ATP and supernatant factors for full activity. A markedrequirement was observed with agrostin among Caryophyllaceae,gelonin among Euphorbiaceae, and with both barley RIP and tritin-Samong Poaceae. The distribution of cofactor requirement in Phytolaccaceaediscriminates leaf forms (cofactor-independent) from seed androot forms (cofactor-dependent). The results are discussed onthe basis of the present knowledge on the tissue localizationof RIPs and on the sensitivity of ribosomes to conspecific RIPs. Key words: Cofactors, ribosome-inactivating proteins, RNA-N-glycosidase, up-regulation 相似文献
119.
Hazem M. Kalaji Gert Schansker Richard J. Ladle Vasilij Goltsev Karolina Bosa Suleyman I. Allakhverdiev Marian Brestic Filippo Bussotti Angeles Calatayud Piotr Dąbrowski Nabil I. Elsheery Lorenzo Ferroni Lucia Guidi Sander W. Hogewoning Anjana Jajoo Amarendra N. Misra Sergio G. Nebauer Simonetta Pancaldi Consuelo Penella DorothyBelle Poli Martina Pollastrini Zdzislawa B. Romanowska-Duda Beata Rutkowska João Serôdio Kancherla Suresh Wiesław Szulc Eduardo Tambussi Marcos Yanniccari Marek Zivcak 《Photosynthesis research》2014,122(2):121-158
The aim of this educational review is to provide practical information on the hardware, methodology, and the hands on application of chlorophyll (Chl) a fluorescence technology. We present the paper in a question and answer format like frequently asked questions. Although nearly all information on the application of Chl a fluorescence can be found in the literature, it is not always easily accessible. This paper is primarily aimed at scientists who have some experience with the application of Chl a fluorescence but are still in the process of discovering what it all means and how it can be used. Topics discussed are (among other things) the kind of information that can be obtained using different fluorescence techniques, the interpretation of Chl a fluorescence signals, specific applications of these techniques, and practical advice on different subjects, such as on the length of dark adaptation before measurement of the Chl a fluorescence transient. The paper also provides the physiological background for some of the applied procedures. It also serves as a source of reference for experienced scientists. 相似文献
120.