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71.
Dalle-Donne I Giustarini D Colombo R Rossi R Milzani A 《Trends in molecular medicine》2003,9(4):169-176
Oxidative modifications of enzymes and structural proteins play a significant role in the aetiology and/or progression of several human diseases. Protein carbonyl content is the most general and well-used biomarker of severe oxidative protein damage. Human diseases associated with protein carbonylation include Alzheimer's disease, chronic lung disease, chronic renal failure, diabetes and sepsis. Rapid recent progress in the identification of carbonylated proteins should provide new diagnostic (possibly pre-symptomatic) biomarkers for oxidative damage, and yield basic information to aid the establishment an efficacious antioxidant therapy. 相似文献
72.
Ilaria?Bartalesi Ivano?BertiniEmail author Giulia?Di?Rocco Antonio?Ranieri Antonio?Rosato Murugendra?Vanarotti Paul?R.?Vasos Maria?Silvia?Viezzoli 《Journal of biological inorganic chemistry》2004,9(5):600-608
The minimal mono-heme ferricytochrome
c from Bacillus pasteurii, containing 71 amino acids, has been further investigated through mutagenesis of different positions in the loop containing the iron ligand Met71. These mutations have been designed to sample different aspects of the loop structure, in order to obtain insights into the determinants of the stability of the iron(III) environment. In particular, positions 68, 72 and 75 have been essayed. Gln68 has been mutated to Lys to provide a suitable alternate ligand that can displace Met71 under denaturing conditions. Pro72 has been mutated to Gly and Ala to modify the range of allowed backbone conformations. Ile75, which is in van der Waals contact with Met71 and partly shields a long-lived water molecule in a protein cavity, has been substituted by Val and Ala to affect the network of inter-residue interactions around the metal site. The different contributions of the above amino acids to protein parameters such as structure, redox potential and the overall stability against unfolding with guanidinium hydrochloride are analyzed. While the structure remains essentially the same, the stability decreases with mutations. The comparison with mitochondrial c-type cytochromes is instructive.Abbreviations Bpcytc
soluble fragment of cytochrome c553 from Bacillus pasteurii
- GdmCl
guanidinium chloride
- I75A
Ile75 to Ala mutant
- I75V
Ile75 to Val mutant
- P72A
Pro72 to Ala mutant
- P72G
Pro72 to Gly mutant
- Q68K
Gln75 to Lys mutant
- WT
wild type 相似文献
73.
74.
Ronaldo?Correia?da?SilvaEmail author Andrei?Santos?Siqueira Alex?Ranieri?Jer?nimo?Lima Adonis?de?Melo Lima Alberdan?Silva?Santos Délia?Cristina?Figueira?Aguiar Evonnildo?Costa?Gon?alves 《Journal of molecular modeling》2018,24(5):108
Asparaginases are found in a range of organisms, although those found in cyanobacteria have been little studied, in spite of their great potential for biotechnological application. This study therefore sought to characterize the molecular structure of an L-asparaginase from the cyanobacterium Limnothrix sp. CACIAM 69d, which was isolated from a freshwater Amazonian environment. After homology modeling, model validation was performed using a Ramachandran plot, VERIFY3D, and the RMSD. We also performed molecular docking and dynamics simulations based on binding free-energy analysis. Structural alignment revealed homology with the isoaspartyl peptidase/asparaginase (EcAIII) from Escherichia coli. When compared to the template, our model showed full conservation of the catalytic site. In silico simulations confirmed the interaction of cyanobacterial isoaspartyl peptidase/asparaginase with its substrate, β-Asp-Leu dipeptide. We also observed that the residues Thr154, Thr187, Gly207, Asp218, and Gly237 were fundamental to protein–ligand complexation. Overall, our results suggest that L-asparaginase from Limnothrix sp. CACIAM 669d has similar properties to E. coli EcAIII asparaginase. Our study opens up new perspectives for the biotechnological exploitation of cyanobacterial asparaginases. 相似文献
75.
Tumour‐associated macrophages correlate with microvascular bed extension in colorectal cancer patients
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Ilaria Marech Michele Ammendola Rosario Sacco Giuseppe Sammarco Valeria Zuccalà Nicola Zizzo Christian Leporini Maria Luposella Rosa Patruno Gianfranco Filippelli Emilio Russo Mariangela Porcelli Cosmo Damiano Gadaleta Giovambattista De Sarro Girolamo Ranieri 《Journal of cellular and molecular medicine》2016,20(7):1373-1380
Tumour‐associated macrophages (TAMs) represent pivotal components of tumour microenvironment promoting angiogenesis, tumour progression and invasion. In colorectal cancer (CRC), there are no conclusive data about the role of TAMs in angiogenesis‐mediated tumour progression. In this study, we aimed to evaluate a correlation between TAMs, TAM immunostained area (TAMIA) microvascular density (MVD), endothelial area (EA) and cancer cells positive to VEGF‐A (CCP‐VEGF‐A) in primary tumour tissue of locally advanced CRC patients undergone to radical surgery. A series of 76 patients with CRC were selected and evaluated by immunohistochemistry and image analysis. An anti‐CD68 antibody was employed to assess TAMs and TAMIA expression, an anti‐CD34 antibody was utilized to detect MVD and EA expression, whereas an anti‐VEGF‐A antibody was used to detect CCP‐VEGF‐A; then, tumour sections were evaluated by image analysis methods. The mean ± S.D. of TAMs, MVD and CCP‐VEGF‐A was 65.58 ± 21.14, 28.53 ± 7.75 and 63% ± 37%, respectively; the mean ± S.D. of TAMIA and EA was 438.37 ± 124.14μ2 and 186.73 ± 67.22μ2, respectively. A significant correlation was found between TAMs, TAMIA, MVD and EA each other (r ranging from 0.69 to 0.84; P ranging from 0.000 to 0.004). The high level of expression of TAMs and TAMIA in tumour tissue and the significant correlation with both MVD and EA illustrate that TAMs could represent a marker that plays an important role in promoting angiogenesis‐mediated CRC. In this context, novel agents killing TAMs might be evaluated in clinical trials as a new anti‐angiogenic approach. 相似文献
76.
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78.
Cytoskeleton and adhesion patterns of cultured chick embryo chondrocytes during cell spreading and Rous sarcoma virus transformation 总被引:5,自引:0,他引:5
Pier Carlo Marchisio Olga Capasso Lucio Nitsch Ranieri Cancedda Elisa Gionti 《Experimental cell research》1984,151(2):332-343
The cytoskeleton and the adhesion complex of chick embryo chondrocytes maintained in vitro have been studied by fluorescence and interference reflection microscopy during the process of cell spreading. The pattern of actin-containing microfilaments and the distribution of vinculin speckles on adhesion plaques have been found to change as a function of the culture time. Newly plated chondrocytes adhere to the substratum mostly around a peripheral ring-like region and show a complex tridimensional array of microfilaments. When chondrocytes flatten, they develop stress fibres and show a diffuse system of vinculin-containing adhesion plaques scattered over the entire ventral side of the cells. Upon infection with Rous sarcoma virus (RSV) chondrocytes display one or more actin-containing ruffles located on the dorsal side similar to the 'actin flowers' earlier described in other cell types. These structures have been found to accumulate vinculin too. In chondrocytes infected with two td-ts mutants of RSV, 'actin flowers' have been found to persist at the restrictive temperature. At this temperature, however, in the majority of cells, stress fibres and adhesion plaques reappear. 相似文献
79.
Ranieri Rolandi Mauro Robello Carla Mao Paolo Mainardi Gabriella Besio 《Cell biochemistry and biophysics》1990,16(1-2):71-83
The interaction of the negatively-charged phosphatidylserine (PS) and γ-Aminobutyric acid (GABA) is examined in black lipid membranes (BLM) and inverse micelles. GABA does not permeate through PS membranes and, in concentrations of 10?5-10?4 M, it reduces the negative potential at the membrane-aqueous solution interface. The effect is owing to the adsorption of the GABA cationic species and the consequent decrease of the negative surface charge density of the membrane. When the intrinsic pH of the membrane-solution interface is considered, the Gouy-Chapman-Stern theory describes the GABA screening effect and makes it possible to calculate the GABA-PS binding constant. This value is compared with that obtained measuring the partition of14C-GABA between an organic phase containing PS and the aqueous solution. The results presented strongly suggest that the electrostatic force plays a major role in GABA-PS interaction. 相似文献
80.
Brigida D’Abrosca Elisabetta Buommino Grazia D’Angelo Lorena Coretti Monica Scognamiglio Valeria Severino Severina Pacifico Giovanna Donnarumma Antonio Fiorentino 《Bioorganic & medicinal chemistry》2013,21(22):7038-7046
Two new acylated styrylpyrones, one 5-methoxy-1(3H)-isobenzofuranone glucoside and a hydroxymethyl-orcinol derivative, along with sixteen known aromatic metabolites, including lignans, quinic acid derivatives low-molecular weight phenol glucosides, have been isolated from the methanol extract of Helichrysum italicum, a medicinal plant typical of the Mediterranean vegetation. The structures of these compounds have been elucidated on the basis of extensive 2D-NMR spectroscopic analyses, including COSY, TOCSY, HSQC, CIGAR-HMBC, H2BC and HSQC-TOCSY, along with Q-TOF HRMS2 analysis. Selected compounds were evaluated for their anti-biofilm properties against Pseudomonas aeruginosa. 相似文献