Typewritten copy / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide,

Thesis (Ph.D.)---University of Adelaide. / Typewritten copy.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1961. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Illinois State University, 1987. / Title from title page screen, viewed August 22, 2005. Dissertation Committee: Robert L. Preston (chair), George W. Kidder, Jim N. Tone, John L. Frehn, Wayne A. Riddle. Includes bibliographical references (leaves 209-216) and abstract. Also available in print.

No description available.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 182-191).

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

No description available.

The coenzyme B12-dependent enzyme glutamate mutase (E.C. 5.4.99.1) catalyses the rearrangement of (2S)-glutamic acid to (2S,3S)-3-methylaspartic acid. Each of the two components of the enzyme was purified to homogeneity using a combination of low and high performance chromatographic techniques. Component E and S displayed molecular weights of 53 KDa and 13 KDa respectively as determined by gel electrophoresis, contrary to literature reports. A large number of glutamate and 3-methylaspartate analogues were synthesised and tested as substrates for the enzyme from Clostridium tetanomorphum. No rearrangement products could be detected for (2S,3R)-3-methylaspartic acid, (2S,3S)-3-ethylaspartic acid, 3-methylglutamic acid, (2S,3R)-3-methylsuccinic acid or A/-methyl-3-methylaspartic acid. Five inhibitors were discovered for the enzyme. Four of them were typical competitive inhibitors: (2S,3S)- and (2S,3R)-3-methylglutamates (Ki = 1.0 mM and Ki = 1.5 mM respectively); (2S)-homocysteic acid, Ki = 5 mM; and 1-bromo-cis-1,2-cyclopropanedicarboxylic acid (Ki= 2.2+/-0.2 mM). Finally 1-bromo-trans-1,2- cyclopropanedicarboxylic acid prevented the enzyme from processing (2S)- glutamic acid for periods of times proportional to its concentration. Our results support a radical mechanism with a protein bound glycyl radical as an intermediate, and provide evidence for the existence of two distinct conformations of the holoenzyme, prior to and after the activation of the cofactor. (2S,3R)-3- and (2S,3S)-3-Methylglutamic acids were synthesised stereospecifically by extending Schollkopf's bis-lactim ether methodology. The attack of various carbon anions at C-5 of isopropyl N-benzyl-(4S,5R)-1,2,3- oxathiazolidone-5-methyi-4-carboxyiate S,S-dioxide was not a versatile pathway. Nevertheless, the reaction of the oxathiazolidone with an allylmagnesium lithium cuprate complex gave some promising results, but more research is necessary to optimise certain problematic steps. Several different routes were evaluated for the preparation of 1-amino-1,2-cyciopropanedicarboxylic acid, but either low yields or instability of intermediates thwarted any attempts to achieve this goal. Finally 1- bromo-cis-and trans-1,2-cyclopropanedicarboxylic acids were synthesised by reacting methyl acrylate with methyl dibromoacetate in the presence of sodium hydride. The two pairs of enantiomers, cis- ((2S,3S) and (2R,3R)) and trans- ((2R,3S) and (2S,3R)) were separated by selective ester formation.

Preliminary studies have been undertaken on the enzyme, glutamate mutase. Stereochemically pure (2S,3S)-3-ethylaspartic acid has been synthesized. The turnover of this substrate analogue by glutamate mutase has been investigated. Possible reaction products have been synthesized. (2S,3S)-[1',1',2',2',2'-2H]-3-Ethylaspartic acid has been prepared and a novel synthesis of [1-2H]-ethanol has been investigated with the aim of preparing (2S,3S)-[1'-2H]-3-ethylaspartic acid. In order to investigate the mechanism of elimination of ammonia from (2S,3R)-3-methylaspartic acid, by the enzyme 3-methylaspartase, stereospecific routes to (2S,3R)-3-methylaspartic acid and [3-2H]-(2S,3R)-3-methylaspartic acid have been explored. The compounds were obtained in high enantiomeric excess and with >97 % incorporation of deuterium into the latter. It has been demonstrated that 3-methylaspartase catalyses the direct elimination of ammonia from these substrates, presumably by a syn- elimination mechanism. The kinetic parameters, Vmax and Km, have been determined for both compounds at 1 and 50 mM potassium ion concentrations. A deuterium isotope effect on (D(V)) of 7.15 +/- 2.74 was measured for the reaction at 1 mM potassium ion concentration. A large D(V) of 6.79 + 0.92 was also observed at 50 mM potassium ion concentration, in contrast to results with the natural isomer which show the effect is completely suppressed at this potassium ion concentration. Values for D(V/K) were also obtained at 1 and 50 mM potassium ion concentrations. They were 3.39 +/- 1.6 and 4.10 +/- 1.3, respectively. The 15N isotope effect on V/K was measured at 1 mM potassium ion concentration. A value of 1.0028 +/- 0.0040 was observed for (2S,3R)-3-methylaspartic acid, and, a value of 1.0033 +/- 0.0043 observed for [3-2H]-(2S,3R)-3-methylaspartic acid.