<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis"^^ . "Iron is the most abundant trace element in the human body and zinc is the second one. Control of ion homeostasis is of vital importance for mammals and bacteria. Regulation of the ion flux into or out of the cell is a complex and articulated mechanism that still needs to be elucidated. The highly specialized pathogen Mycobacterium tuberculosis has to contend with iron sequestration in order to survive in the human body. Iron metabolism is regulated by controlling transcription of genes involved in iron uptake, transport and storage. Paucity of this metal triggers an extensive response to increase iron acquisition whereas an excess of it can be toxic for the cell. The control of intracellular iron concentration is also linked to other important processes including oxidative stress response and the regulation of virulence factors. Recent studies have shown that, in patients affected by TB/HIV exposed to high level of dietary iron, the risk of active pulmonary tuberculosis increases. In M. tuberculosis the ferric uptake regulator A (FurA) is activated by Fe2+ to bind specifically to its target DNA sequence thereby repressing the downstream genes. Zinc is also an important element for all living organisms and serves as a cofactor in all six classes of enzymes and also in several regulatory proteins. The intracellular concentration of this metal must be carefully regulated due its toxicity. Compared with eukaryotes, little is known about zinc homeostasis in bacteria. In the tuberculosis genome several genes coding for zinc proteins have been classified but curiously no zinc regulator has been yet defined. Surprisingly, instead, two Fur genes were identified: Mtb furA and Mtb furB, but no clear structural or functional distinction has been reported. In this thesis a careful and detailed structural and biological description of FurA and FurB proteins is presented. Using a variety of biochemical and biophysical methods - including electrophoretic mobility shift assay (EMSA), site directed mutations, isothermal calorimetry (ITC), microPIXE analysis, extended X-ray absorption fine spectroscopy (EXAFS) and X-ray crystallography - we investigated the metal binding sites together with the nature and the structure of these proteins. The combination of these results enable us to distinguish between structurally and functionally distinct metal binding sites, provide a meticulous description and qualitative and quantitative characterization of them, propose biological roles and present for the first time a 3D picture of a zinc uptake regulator."^^ . "2006" . . . . . . . . "Debora"^^ . "Lucarelli"^^ . "Debora Lucarelli"^^ . . . . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (PDF)"^^ . . . "ThesisLucarelli.pdf"^^ . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (Other)"^^ . . . . . . "preview.jpg"^^ . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (Other)"^^ . . . . . . "medium.jpg"^^ . . . "Structural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #7094 \n\nStructural Studies on Ferric Uptake Regulator Proteins from Mycobacterium tuberculosis\n\n" . "text/html" . . . "570 Biowissenschaften, Biologie"@de . "570 Life sciences"@en . .