Investigation of the central regulation of taste perception and metabolism in human and animal experiments

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Network analysis of protein dynamics

The network paradigm is increasingly used to describe the topology and dynamics of complex systems. Here we review the results of the topological analysis of protein structures as molecular networks describing their small-world character, and the role of hubs and central network elements in governing enzyme activity, allosteric regulation, protein motor function, signal transduction and protein stability. We summarize available data how central network elements are enriched in active centers and ligand binding sites directing the dynamics of the entire protein. We assess the feasibility of conformational and energy networks to simplify the vast complexity of rugged energy landscapes and to predict protein folding and dynamics. Finally, we suggest that modular analysis, novel centrality measures, hierarchical representation of networks and the analysis of network dynamics will soon lead to an expansion of this field.Comment: 10 pages, 2 figures, 1 tabl

Synthesis, physico-chemical characterization and bacteriostatic study of Pt complexes with substituted amine ligands

Three complexes of general formula PtCl2R2 were synthesized, where R is the amine ligand with aromatic substituents. Coordination compounds [Pt(an)2Cl2] (1), [Pt(pa)2Cl2] (2) and [Pt(aph)2Cl2] (3), where an = 2-aminonaphthalene, pa = 2-aminopyrimidine, aph = 4-anilinophenol, were characterized by on-line coupled TG/DTA-MS, powder XRD and spectroscopic techniques (FTIR, ESI–MS and NMR), and tested against selected Gram(+) and Gram(–) bacteria. The thermal data show that all three compounds contain lattice or absorbed water, and the stability of the anhydrous compounds in nitrogen decreases in the order 2 > 1 > 3. Above 200 °C, the complexes loose characteristic fragments of their ligands. The spectroscopic data are in accordance with the thermal properties of the samples and prove their composition. The compounds are more effective inhibitors of Gram(+) than Gram(−) bacteria. © 2016 Akadémiai Kiadó, Budapest, Hungar

Novel cobalt complexes with glyoximes : synthesis, physicochemical analysis and biological study

Azomethine derivatives have several applications, especially as reagents for the determination of transition metal ions. Furthermore these ligands and their cobalt complexes were also reported to possess biological activities, such as antimicrobial, anti-tubercular, anticonvulsant, anti-inflammatory, anti-proliferative activities as well as antifungal inhibition potential [1]. Another reason for using metal-containing compounds as structural scaffolds is related to the kinetic stability of their coordination spheres in the biological environment. Metallic ions have been shown to play important role in the biological activity of different compounds in such away that, in some cases, activity is enhanced or only takes place in the presence of these ions [2]. In our research new cobalt(III) complexes were synthesized with -glyoximes, azides, amines, thiocyanate and halogens, such as [Co(Me-propyl-GlyoxH)2(N3)(amine)], [Co(Mepentyl-GlyoxH)2(N3)(amine)], [Co(Et-propyl-GlyoxH)2(N3)(amine)], [Co(Et-propylGlyoxH)2(Br)(amine)], [Co(Et-propyl-GlyoxH)2(SCN)(amine)], H[Co(Et-propylGlyoxH)2(SCN)2], [Co(phenyl-Me-GlyoxH)2(amine)2]I, [Co(Et-propyl-GlyoxH)2(amine)2]I, [Co(Et-Bu-GlyoxH)2(amine)2]I, where GlyoxH = mono deprotonated glyoxime, and the used amines: imidazole, 3-hydroxy-aniline, lepidine, 3,5-dimethyl-pyridine, di(n-butyl)-amine, diisopropyl-amine, 2-amino-pyrimidine, diphenyl-amine, 2-picoline, 3-picoline. The Co(II)- acetate salt dissolved in water and mixed with the glyoxime alcoholic solution was oxidized by air bubbling, then the corresponding diamines and the other complexing agents were added. The molecular structure of our products was investigated by IR, UV–VIS spectroscopy, mass spectrometry (MS), thermoanalytical measurements (TG-DTG-DTA), and powder XRD. The biological activity, like antimicrobial effect, was studied for a few bacteria

Novel platinum complexes with schiff bases and α-Dioximes, their physico-chemical and biological study

In our research project we prepared the following platinum(II) complexes with Schiff bases and -dioximes, such as [Pt(ketone)2A(L2)], (ketone: 2-heptanone, 2-octanone, 3-octanone; A: hydrazine, phenylhydrazine, o-phenylene-diamine; L: 1-naphthylamine, 2-aminopyrimidine, 2-methylimidazole, 2-amino-4-methylpyridine) and [Pt(DioxH)2L2], (DioxH2: methyl-phenyl-dioxime, butyl-methyl-dioxime; L: 1-naphthylamine, 2-methylimidazole, 2-amino-4-methylpyridine, lepidine, 2-methylpyridine, m-toluidine, dicyclohexylamine, 4-isopropylamine, cyclohexylamine), by the reaction of PtCl2 in suitable solvent. After a short bibliographical survey, involving the classification and evolution of platinum complexes with possible applications, we analyzed their physico-chemical properties using FTIR, Raman, NMR, UV-VIS spectroscopy, powder X-ray diffraction (XRD), mass spectrometry, thermal analysis (TG, DTG, DTA) and SEM. We also studied the antibacterial effect of complexes on different strains of bacteria. This class of compounds has relevance in biochemistry, some of them are antibacterial agents and potential anti-tumor drugs