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91.
92.
Ganoderma microsporum immunomodulatory protein induces apoptosis and potentiates mitomycin C‐induced apoptosis in urinary bladder urothelial carcinoma cells 下载免费PDF全文
93.
Synonymous substitution rates have been shown to vary among evolutionary
lineages of both nuclear and organellar genes across a broad range of
taxonomic groups. In animals, rate heterogeneity does not appear to be
correlated across nuclear and mitochondrial genes. In this paper, we
contrast substitution rates in two plant groups and show that grasses
evolve more rapidly than palms at synonymous sites in a mitochondrial, a
nuclear, and a plastid gene. Furthermore, we show that the relative rates
of synonymous substitution between grasses and palms are similar at the
three loci. The correlation in synonymous substitution rates across genes
is particularly striking because the three genes evolve at very different
absolute rates. In contrast, relative rates of nonsynonymous substitution
are not conserved among the three genes.
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94.
Dam TK Cavada BS Grangeiro TB Santos CF Ceccatto VM de Sousa FA Oscarson S Brewer CF 《The Journal of biological chemistry》2000,275(21):16119-16126
Lectins from seven different species of the Diocleinae subtribe have been recently isolated and characterized in terms of their carbohydrate binding specificities (Dam, T. K., Cavada, B. S., Grangeiro, T. B., Santos, C. F., de Sousa, F. A. M., Oscarson, S., and Brewer, C. F. (1998) J. Biol. Chem. 273, 12082-12088). The lectins included those from Canavalia brasiliensis, Cratylia floribunda, Dioclea rostrata, Dioclea virgata, Dioclea violacea, and Dioclea guianensis. All of the lectins exhibited specificity for Man and Glc residues, but much higher affinities for the branched chain trimannoside, 3,6-di-O-(alpha-d-mannopyranosyl)-d-mannose, which is found in the core region of all asparagine-linked carbohydrates. In the present study, isothermal titration microcalorimetry is used to determine the binding thermodynamics of the above lectins, including a new lectin from Canavalia grandiflora, to a complete series of monodeoxy analogs of the core trimannoside. From losses in the affinity constants and enthalpies of binding of certain deoxy analogs, assignments are made of the hydroxyl epitopes on the trimannoside that are involved in binding to the lectins. The pattern of binding of the deoxy analogs is similar for all seven lectins, and similar to that of concanavalin A which is also a member of the Diocleinae subtribe. However, differences in the magnitude of the thermodynamic binding parameters of the lectins are observed, even though the lectins possess conserved contact residues in many cases, and highly conserved primary sequences. The results indicate that non-contact residues in the lectins, even those distant from the binding sites, modulate their thermodynamic binding parameters. 相似文献
95.
K Mann C M Farias F G Del Sol C F Santos T B Grangeiro C S Nagano B S Cavada J J Calvete 《European journal of biochemistry》2001,268(16):4414-4422
A mannose/glucose-specific lectin was isolated from seeds of Parkia platycephala, the most primitive subfamily of Leguminosae plants. The molecular mass of the purified lectin determined by mass spectrometry was 47 946 +/- 6 Da (by electrospray ionization) and 47 951 +/- 9 Da (by matrix-assisted laser-desoption ionization). The apparent molecular mass of the lectin in solutions of pH in the range 4.5-8.5 determined by analytical ultracentrifugation equilibrium sedimentation was 94 +/- 3 kDa, showing that the protein behaved as a non-pH-dependent dimer. The amino-acid sequence of the Parkia lectin was determined by Edman degradation of overlapping peptides. This is the first report of the primary structure of a Mimosoideae lectin. The protein contained a blocked N-terminus and a single, nonglycosylated polypeptide chain composed of three tandemly arranged homologous domains. Each of these domains shares sequence similarity with jacalin-related lectin monomers from Asteraceae, Convolvulaceae, Moraceae, Musaceae, Gramineae, and Fagaceae plant families. Based on this homology, we predict that each Parkia lectin repeat may display a beta prism fold similar to that observed in the crystal structure of the lectin from Helianthus tuberosus. The P. platycephala lectin also shows sequence similarity with stress- and pathogen-upregulated defence genes of a number of different plants, suggesting a common ancestry for jacalin-related lectins and inducible defence proteins. 相似文献
96.
Alfa U. Bari Helton C. Silva Mayara T. L. Silva Francisco N. Pereira Júnior João B. Cajazeiras Alexandre H. Sampaio Rodrigo B. Leal Edson H. Teixeira Bruno A. M. Rocha Kyria S. Nascimento Celso S. Nagano Benildo S. Cavada 《Journal of molecular recognition : JMR》2013,26(8):351-356
A new mannose/glucose‐specific lectin, named DigL, was purified from seeds of Dialium guineense by a single step using a Sepharose 4b‐Mannose affinity chromatography column. DigL strongly agglutinated rabbit erythrocytes and was inhibited by d ‐mannose, d ‐glucose, and derived sugars, especially α‐methyl‐d ‐mannopyranoside and N‐acetyl‐d ‐glucosamine. DigL has been shown to be a stable protein, maintaining its hemagglutinating activity after incubation at a wide range of temperature and pH values and after incubation with EDTA. DigL is a glycoprotein composite by approximately 2.9% of carbohydrates by weight. By sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, the purified DigL exhibited an electrophoretic profile consisting of a broad band of 28–30 kDa. Analysis using electrospray ionization mass spectrometry indicated that purified DigL possesses a molecular average mass of 28 452 ± 2 Da and shows the presence of possible glycoforms. In addition, DigL exhibited an intermediary toxic effect on Artemia sp. nauplii, and this effect was both dependent on native structure and mediated by a carbohydrate‐binding site. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
97.
Flávio de Oliveira Silva Priscila das Neves Santos Cristiane Moutinho Lagos de Melo Edson Holanda Teixeira Benildo Sousa Cavada Francisco Vassiliepe Sousa Arruda João Batista Cajazeiras Alysson Chaves Almeida Valéria Rêgo Alves Pereira Ana Lúcia Figueiredo Porto 《Cell and tissue research》2011,346(3):457-457
98.
JC polyomavirus (JCPyV) is a common human pathogen that results in a chronic asymptomatic infection in healthy adults. Under conditions of immunosuppression, JCPyV spreads to the central nervous system and can cause the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML), a disease for which there are no vaccines or antiviral therapies. Retro-2 is a previously identified small molecule inhibitor that was originally shown to block retrograde transport of toxins such as ricin toxin from endosomes to the Golgi apparatus and endoplasmic reticulum (ER), and Retro-2.1 is a chemical analog of Retro-2 that has been shown to inhibit ricin intoxication of cells at low nanomolar concentrations. Retro-2 has previously been shown to prevent retrograde transport of JCPyV virions to the ER, but the effect of Retro-2.1 on JCPyV infectivity is unknown. Here it is shown that Retro-2.1 inhibits JCPyV with an EC50 of 3.9 μM. This molecule inhibits JCPyV infection at dosages that are not toxic to human tissue culture cells. Retro-2.1 was also tested against two other polyomaviruses, the human BK polyomavirus and simian virus 40, and was also shown to inhibit infection at similar concentrations. Viral uncoating studies demonstrate that Retro-2.1 inhibits BKPyV infectivity in a manner similar to Retro-2. These studies demonstrate that improved analogs of Retro-2 can inhibit infection at lower dosages than Retro-2 and further optimization of these compounds may lead to effective treatment options for those suffering from JCPyV infection and PML. 相似文献
99.
Helton C. Silva Alfa U. Bari Bruno Anderson M. Rocha Kyria S. Nascimento Edson L. Ponte Alana F. Pires Plínio Delatorre Edson H. Teixeira Henri Debray Ana Maria S. Assreuy Celso S. Nagano Benildo S. Cavada 《Journal of molecular recognition : JMR》2013,26(10):470-478
Parkia biglobosa (subfamily Mimosoideae), a typical tree from African savannas, possess a seed lectin that was purified by combination of ammonium sulfate precipitation and affinity chromatography on a Sephadex G‐100 column. The P. biglobosa lectin (PBL) strongly agglutinated rabbit erythrocytes, an effect that was inhibited by d ‐mannose and d ‐glucose‐derived sugars, especially α‐methyl‐d ‐mannopyranoside and N‐acetyl‐d ‐glucosamine. The hemagglutinating activity of PBL was maintained after incubation at a wide range of temperature and pH and also was independent of divalent cations. By sodium dodecyl sulfate–polyacrylamide gel electrophoresis analysis, PBL exhibited an electrophoretic profile consisting of a single band with apparent molecular mass of 45 kDa. An analysis using electrospray ionization–mass spectrometry indicated that purified lectin possesses a molecular average mass of 47 562 ± 4 Da, and the analysis by gel filtration showed that PBL is a dimer in solution. The complete amino acid sequence of PBL, as determined using tandem mass spectrometry, consists of 443 amino acid residues. PBL is composed of a single non‐glycosylated polypeptide chain of three tandemly arranged jacalin‐related domains. Sequence heterogeneity was found in six positions, indicating that the PBL preparations contain highly homologous isolectins. PBL showed important antinociceptive activity associated to the inhibition of inflammatory process. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
100.
Rômulo Farias Carneiro Arthur Alves de Melo Fernando Edson Pessoa do Nascimento Clareane Avelino Simplicio Kyria Santiago do Nascimento Bruno Anderson Matias da Rocha Silvana Saker‐Sampaio Raniere da Mata Moura Sula Salani Mota Benildo Sousa Cavada Celso Shiniti Nagano Alexandre Holanda Sampaio 《Journal of molecular recognition : JMR》2013,26(1):51-58
Two new lectins named Halilectin 1 (H‐1) and Halilectin 2 (H‐2) were isolated from the marine sponge Haliclona caerulea using a combination of affinity chromatography on stroma fixed onto Sephadex G‐25 and cation and anion exchange chromatography. H‐1 is a monomeric protein with a molecular mass of 40 kDa estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and 15 kDa estimated using a TSK gel. Conversely, H‐2 is a homodimeric protein with 15 kDa monomers linked via weak interactions. H‐1 more effectively agglutinates trypsinized rabbit erythrocytes, whereas H‐2 more effectively agglutinates native rabbit erythrocytes. The hemagglutinating activity of H‐1 could be not inhibited by any tested sugars, but H‐2 was inhibited by orosomucoid and porcine stomach mucin. Neither lectin was dependent on divalent ions. H‐1 was stable at basic pH range and temperatures up to 50 °C, whereas H‐2 was stable at acid pH range and temperatures up to 80 °C. The H. caerulea lectins exhibited dose‐dependent toxicity against Artemia nauplii. Additionally, 76% of the primary structure of H‐2 was determined using tandem mass spectrometry to contain a unique amino acid sequence with no similarity to any members of the animal lectin family. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献