Regensburg, Univ., Diss., 2009.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (sites viewed on August 10, 2006). PDF text of dissertation: 98 p. : ill. ; 1.16Mb. UMI publication number: AAT 3208087. Includes bibliographical references. Also available in microfilm, microfiche and paper format.

The current work was undertaken to test the ability of avidin to affect the course of leukemia when administered intraperitoneally.

<b>Transition Metal Catalyzed Alkylation</b> We have reported methodology for the use of methanol as an alkylation reagent using catalytic rhodium or iridium species for the formation of branched products from methyl ketones. The synthetic utility of the dialkylated products was enhanced by performing a regioselective Baeyer-Villiger oxidation which allowed access to ester products. A range of different phosphine ligands were screened, and sterically hindered and electron rich phosphine ligands were found to favour the formation of enone and methoxy adducts under an O2 atmosphere. This interrupted hydrogen borrowing reaction enabled the in situ addition of a nucleophile to give more complex products. A range of tetrasubsitituted pyridines were then synthesized from 1, 5-dicarbonyl compounds formed in the methylenation/conjugate addition sequence. Finally, deuteration experiments suggest that the reaction proceeds via a monohydride mechanism, and the possibilities for the beneficial effect of O2 were discussed. <b>Synthesis of biotin derivatives</b> The streptavidin-biotin system was chosen for the studies of protein/ligand interactions at molecular level. A series of modified biotin ligands were designed and synthesized to introduce repulsive interations with streptavidin. The protein/ligand complexes were analyzed at high resolution by X-ray crystallography.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 165-172).

Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 2000? / Bibliography: leaves 130-159.

Ulm, Univ., Diss., 2007.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [66]-73).

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 101-118).

A soluble enzyme system, isolated from livers of biotin-deficient rats, catalyzes the ATP-dependent synthesis of propionyl holocarboxylase from d-biotin and propionyl apocarboxylase. This system has been resolved by alumina C_∂ gel fractionation into two essential components; (a) gel supernatant which contains propionyl apocarboxylase and (b) gel eluate which contains an enzyme which catalyzes the covalent bonding of d-biotin to propionyl apocarboxylase. The propionyl holocarboxylase synthesis catalyzed by these enzyme systems is irreversible and d·biotin specific. The gel supernatant has been further purified by hydroxyapatite chromatography and (NH₄)₂SO₄ fractionation and the gel eluate by (NH₄)₂SO₄ precipitation and cellulose-phosphate chromatography. An enzyme similar to the gel eluate enzyme has been isolated from cell-free extracts of Propionibacterium shermanii. Although cell-free extracts of P. shermanii do not contain propionyl apo- or holocarboxylase, they do catalyze ATP-dependent propionyl holocarboxylase formation from d·biotin and rat liver propionyl apocarboxylase. Biotin-2'-C¹⁴-labelled propionyl holocarboxylaae, synthesized with these enzyme systems, does not transfer C¹⁴O₂ to propionyl-CoA indicating that the ureido carbon of enzyme-bound biotin is not the"active carbon" of biotin. / Master of Science