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1.
Structure and function of hemoglobin in antarctic fishes and evolutionary implications 总被引:2,自引:0,他引:2
Guido di Prisco Rossana D'Avino Laura Camardella Carla Caruso Mario Romano Bruno Rutigliano 《Polar Biology》1990,10(4):269-274
Summary The hematological features of cold-adapted, red-blooded Antarctic teleosts has prompted this study on the relationship between hemoglobin molecular structure and oxygen-binding properties. The hemolysates from 21 species of 5 families contained one component (Hb 1), often accompanied by an additional, minor one (Hb 2, 5%–10% of total). On the other hand, 3 species of Zoarcidae, a non-endemic family, had 4–5 components. All purified hemoglobins from the former group, but only 1–2 of the 4–5 hemoglobins of Zoarcidae, showed a strong Root effect (pH regulation of oxygen binding). Globins from each hemoglobin have been purified and characterised with respect to molecular structure in several species. The similarity between the complete amino acid sequence of one -chain and those of non-Antarctic -chains is lower than that among the latter sequences, suggesting independent pathways of evolution.Presented at the 5th SCAR Symposium on Antarctic Biology, Hobart, Australia (August 29th-September 3rd, 1988) 相似文献
2.
Summary The complete amino acid sequence of the single haemoglobin of the Antarctic fish Aethotaxis mitopteryx DeWitt has been established by automated repetitive Edman degradation on the intact and cleaved (enzymatically and chemically) and chains. A very high sequence identity with other Antarctic fish haemoglobins has been detected. The haemoglobin has a moderate Bohr effect and no Root effect. Organic phosphates and chloride also regulate oxygen binding only to a moderate extent. The lack of Root effect is consistent with the substitution His — Val at the HC3 C-terminal position of the chain. The low overall heat of oxygenation suggests that in this species oxygen transport is an energy-saving process, presumably related to cold adaptation. The comparative analysis of the haemoglobins of Antarctic fishes emphasises some unique features of the oxygen-transport system of A. mitopteryx, which are likely to be related to its also rather unique mode of life.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundation 相似文献
3.
4.
Maura Turriani Rossana Pesi Antonella Nardone Gino Turchi Francesco Sgarrella Pier Luigi Ipata Maria Grazia Tozzi 《Journal of biochemical and molecular toxicology》1994,9(1):51-57
Nucleoside phosphotransferase acting on inosine and deoxyinosine has been partially purified from cultured Chinese hamster lung fibroblasts (V79). The activity is associated with a cytosolic 5′-nucleotidase acting on IMP and deoxyIMP. The transfer of the phosphate group from IMP to inosine catalyzed by this enzyme was activated by ATP and 2,3-bisphosphoglycerate. Inosine, deoxyinosine, guanosine, deoxyguanosine, and the nucleoside analogs 2′,3′-dideoxyinosine and 8-azaguanosine are substrates, while adenosine and deoxyadenosine are not. IMP, deoxyIMP, GMP, and deoxyGMP are the best phosphate donors. The cytosolic 5′-nucleotidase/phosphotransferase substrate, 8-azaguanosine, was found to be very toxic for cultured fibroblasts (LD50 = 0.32 μM). Mutants resistant to either 8-azaguanosine and the correspondent base 8-azaguanine were isolated and characterized. Our results indicated that the 8-azaguanosine-resistant cells were lacking both cytosolic 5′-nucleotidase and hypoxanthine-guanine phosphoribosyltransferase, while 8-azaguanine resistant cells were lacking only the latter enzyme. Despite this observation, both mutants displayed 8-azaguanosine resistance, thus indicating that cytosolic 5′-nucleotidase is not essential for the activation of this nucleoside analog. 相似文献
5.
Stefano Corsano Giovannella Strappaghetti Rossana Scapicchi Olimpia Scalise 《Bioorganic & medicinal chemistry letters》1993,3(12):2713-2716
The synthesis and evaluaton of the biological activity of a series of 3(2H)-pyridazinones is reported. The bronchodilatating activity of these compounds was determined on the guinea pig trachea. Compounds 6 and 17 with 1-(4-amino-3,5-dichlorophenyl)-2-hydroxyethyl-and 1-(3,4-dichlorophenyl)-2-hydroxyethyl groups linked through a piperazine ring to the 6-position of 3(2H)-pyridazinone show a good bronchospasmolytic activity. 相似文献
6.
Cloning and molecular characterization of two genes encoding adhesion proteins involved in Trichomonas vaginalis cytoadherence 总被引:11,自引:2,他引:9
7.
Signalling of Trichomonas vaginalis for amoeboid transformation and adhesin synthesis follows cytoadherence 总被引:2,自引:0,他引:2
Rossana Arroyo Arturo González-Robles Adolfo Martínez-Palomo J. F. Alderete 《Molecular microbiology》1993,7(2):299-309
The cytoadherence of Trichomonas vaginalis, the sexually transmitted flagellated protozoan, to vaginal epithelial cells (VECs) is the key to infection. Electron microscopy revealed that in vitro-grown parasites having typical globular shape transformed rapidly after contact with VECs into thin, flat, amoeboid cells, maximizing the area of adhesion to the surface of VECs. Amoebic trichomonads formed filopodia and pseudopodia, which interdigitated at distinct sites on the plasma membrane of target cells. In contrast, the amoeboid transformation did not occur for T. vaginalis interacting with He La cells, the previously used in vitro host model cell. Initial parasitism of VECs by a single organism was followed by establishment of a monolayer of trichomonads on the host cell. Finally, parasites adhering to either VECs or HeLa cells were induced to synthesize greater amounts of the four previously described adhesins. Therefore, distinct signals after contact with either epithelial cell type leads to the morphological transformation and/or induction of adhesin synthesis by T. vaginalis. 相似文献
8.
Rossana Saracino Chiara Capponi Sara Di Persio Carla Boitani Silvia Masciarelli Francesco Fazi Stefania Fera Elena Vicini 《Molecular reproduction and development》2020,87(4):419-429
Glial cell line‐derived neurotrophic factor (GDNF) and retinoic acid (RA) are two molecules crucial for the regulation of the spermatogonial compartment of the testis. During the cycle of the seminiferous epithelium, their relative concentration oscillates with lower GDNF levels in stages where RA levels are high. It has been recently shown that RA negatively regulates Gdnf expression but the mechanisms behind are so far unknown. Here, we show that RA directly downregulates Gdnf mRNA levels in primary murine Sertoli cells through binding of RARα to a novel DR5‐RARE on Gdnf promoter. Pharmacological inhibition and chromatin immunoprecipitation–quantitative polymerase chain reaction analysis suggested that the underlying mechanism involved histone deacetylase activity and epigenetic repression of Gdnf promoter upon RA treatment. 相似文献
9.
Basso Rossana Patricia Poester Vanice Rodrigues Benelli Jéssica Louise Stevens David A. Zogbi Heruza Einsfeld Vasconcellos Izadora Clezar da S. Pasqualotto Alessandro Comarú Xavier Melissa Orzechowski 《Mycopathologia》2021,186(1):109-112
Mycopathologia - Most reports associating fungal infections with COVID-19 have been cases of invasive aspergillosis. Here, we report a case of severe histoplasmosis and COVID-19 infections in an... 相似文献
10.
Daniela Nicole Filoni Rossana Pesi Maria Giovanna Careddu Marcella Camici Simone Allegrini Anita Collavoli 《Nucleosides, nucleotides & nucleic acids》2013,32(12):1155-1160
IMP preferring cytosolic 5 ′-nucleotidase II (cN-II) is a widespread enzyme whose amino acid sequence is highly conserved among vertebrates. Fluctuations of its activity have been reported in some pathological conditions and its mRNA levels have been proposed as a prognostic factor for poor outcome in patients with adult acute myeloid leukemia. As a member of the oxypurine cycle, cN-II is involved in the regulation of intracellular concentration of 5′-inosine monophosphate (IMP), 5′-guanosine monophosphate (GMP), and also 5-phosphoribose 1-pyrophosphate (PRPP) and is therefore involved in the regulation of purine and pyrimidine de novo and salvage synthesis. In addition, several studies demonstrated the involvement of cN-II in pro-drug metabolism. Notwithstanding some publications indicating that cN-II is essential for the survival of several cell types, its role in cell metabolism remains uncertain. To address this issue, we built two eucaryotic cellular models characterized by different cN-II expression levels: a constitutive cN-II knockdown in the astrocytoma cell line (ADF) by short hairpin RNA (shRNA) strategy and a cN-II expression in the diploid strain RS112 of Saccharomyces cerevisiae. Preliminary results suggest that cN-II is essential for cell viability, probably because it is directly involved in the regulation of nucleotide pools. These two experimental approaches could be very useful for the design of a personalized chemotherapy. 相似文献