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1	Purification, Characterization, Crystallization And Preliminary X-ray Structure Determination Of Scytalidium Thermophilum Bifunctional Catalase And Identification Of Its Catechol Oxidase Activity Sutay, Didem 01 June 2007 (has links) (PDF) In this study, the aim was identification and classification of the enzyme having phenol oxidase activity produced by a thermophilic fungus, Scytalidium thermophilum. For this purpose, enzyme production, purification, biochemical characterization and structural analysis by X-ray crystallography studies have been performed. At the beginning of the research, this enzyme was considered as a phenol oxidase and analyzed accordingly. However, during purification, amino acid sequencing and structural studies, the enzyme was shown to be a catalase, with an additional catechol oxidase activity. This novel bifunctional catalase-catechol oxidase (CCO) was purified 10 fold with 45 % yield by anion exchange and gel filtration chromatographies. CCO was determined as a tetrameric protein having total and subunit molecular weights of 320 and 80 kDa, respectively. Isoelectric point of CCO was verified as 5.0. CCO catalase and catechol oxidase activities were characterized in terms of their kinetic behavior at different pH and temperatures. Depending on the substrate specificity and inhibitor studies of CCO, the phenol oxidase activity was determined as catechol oxidase but not tyrosinase or laccase. The best crystallization condition for CCO was determined and X-ray diffraction data was collected at the Daresbury Synchrotron Radiation Source (United Kingdom) at 2.7 &Aring / resolution. The preliminary structure was solved by molecular replacement method using Penicilium vitale catalase structure. CCO was verified to have a tetrameric structure with two homodimers and a metal center in each polypeptide chain. TP Biotechnology 248.13-248.65
2	Lidské glutamátkarboxypeptidasy II a III / Human glutamate carboxypeptidases II and III Navrátil, Michal January 2016 (has links) The herein presented Ph.D. dissertation describes kinetic and structural characterization of human glutamate carboxypeptidases II and III (GCPII and GCPIII) using a complete panel of their natural substrates. These enzymes hydrolyze C-terminal glutamate from their substrates. They share 67 % sequence identity and also similar enzymatic activities. This thesis quantitatively compares human GCPII and GCPIII in terms of their ability to hydrolyze the substrates N-acetyl-L-aspartyl-L-glutamate (NAAG), folyl-poly-γ-L-glutamic acids (FolGlun) and β-citryl-L-glutamate (BCG). We demonstrated that GCPIII hydrolyzes its substrates in a metal- dependent manner, that BCG is a specific substrate of GCPIII, and that NAAG and FolGlun are specific substrates of GCPII. We also provide indirect biochemical evidence that GCPIII might feature a heterometallic active-site cluster. Additionally, we characterized the relevance of a surface exosite of GCPII, the arene-binding site (ABS), for the hydrolysis of FolGlun substrates using mutagenesis and enzyme kinetics and showed that polymorphic His475Tyr variant of GCPII hydrolyzes FolGlun substrates with the same kinetic parameters as the wild-type enzyme. Furthermore, this thesis focuses on structural aspects of the substrate specificities of GCPII and GCPIII: we present...
3	Komplexy 2,6-bis[(N-methylpiperazin-1-yl)methyl]-4-formyl fenolu / Complexes of 2,6-bis[(N-methylpiperazine-1-yl)methyl]-4-formyl phenol Marečková, Vendula January 2012 (has links) Thirteen new dinuclear complexes of ligand 2,6-bis[(N-methylpiperazine-1- yl)methyl]-4-formyl phenol (L1) were prepared. Copper(II) and palladium(II) salts were used for the syntheses. Following compounds were prepared: [Cu2L1(CH3COO)2]ClO4, [Cu2L1(CF3COO)2(ClO4)][Cu2L1(CF3COO)2]ClO4, [Pd2L1(CH3COO)3], [Pd2L1(CF3COO)3], [Pd2L1(Cl)4]. These ones should act as anion receptors. The acetates were exchanged for phenylphosphinates in the case of the complex cation [Cu2L1(CH3COO)2]+ and the structure of [Cu2L1(phPO2H)2]ClO4 was obtained. Geometry of coordination shell of Cu2+ - ions in prepared complexes is tetragonal pyramid. The UV-VIS spectroscopy was used for study of interactions in system of the ligand - metal - anion. Interactions between the ligand and metals in oxidation state 2 were observed as well as interactions between the complex [Cu2L1(CH3COO)2]ClO4 and sodium salts.
4	Synthese und Charakterisierung von Verbindungen der Lanthanoide mit σ-gebundenen Liganden / Synthesis and characterization of compounds of the rare earth elements with σ-donor ligands Hofmeister, Anja 01 July 2008 (has links) No description available. 540 Chemie Mathematics and Computer Science Seltene Erden homoleptische Komplexverbindungen mehrzähnige σ-Donorliganden Biphenylide Benzylide Makrozyklen mit N-Donorfunktionen Lanthanoid-Cluster Röntgenstrukturanalyse. Rare earth elements homoleptic complexes polydentate σ-donor ligands biphenylene benzylen macrocycles with N-donor function rare-earth-Cluster X-ray structure determination. 35.43 35.45 SOC 250: Metallkomplexe Chelate {Chemie: Verbindungstypen}

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