Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2006. / Includes bibliographical references (leaves 131-137). Also available in electronic version.

No description available.

published_or_final_version / abstract / Microbiology / Master / Master of Philosophy

No description available.

The activity of S-adenosyl-L-methionine Decarboxylase (E. C. 4.1.1.50) was measured in two different normal and five different tumorous mouse mananary tissue samples. The soluble fraction was assayed for SAM decarboxylase activity using 14COOHlabeled SAM as the substrate. The amount of 14002 evolved was measured using a liquid scintillation counter.There was a significant elevation of SAM decarboxylase activity in the tumor sample group. The activities of the tumor tissue was x = 15.62 and SD = 8.24. The activity in the normal samples was too low to measure:These results suggest an increase in not only SAM decarboxylase activity, but also in the levels of spermidine and spermine. These increases are characteristics of cancer cells and may result in changes in enzyme activities and membrane phospholipid composition.

Dissertation (Ph.D.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.

Thesis (Ph.D.)--Michigan State University. Dept. of Chemistry, 2008. / Title from PDF t.p. (viewed on Mar. 30, 2009) Includes bibliographical references. Also issued in print.

Thesis (Ph. D.)--Auburn University. / Abstract. Vita. Includes bibliographical references (p. 127-144).

Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.

Candida albicans is a dimorphic fungus exhibiting either a budding yeast or hyphal phase. A shift from the yeast phase to the hyphal phase can generally be induced by increasing the temperature of incubation from 25°C to 37°C. This shift occurs over a four hour period as approximately 90% of the yeast cells form germ tubes during this time.Interestingly, the specific activity of S-adenosylmethionine synthetase increases during the shift in vegetative cell types and begins to decrease after the 4 hour period. Utilizing the protein synthesis inhibitor tricodermin, we have demonstrated that the increase in specific activity requires de novo protein synthesis.SAM synthetase was characterized (in vitro) by kinetic analysis and response to putative inhibitors. The yeast phase enzyme had an apparent Km of 0.17 mM for methionine, 0.14 mM for ATP and is inhibited by dimethyl-sulfoxide (DMSO), methionine sulfone and methionine sulfoxide. The hyphal phase enzyme has an apparent Km of 0.06 mM for methionine, 0.02 mM for ATP and its activity is enhanced by the three inhibitors. This preliminary data suggests the presence of isozymes in Candida albicans and the possibility of morphology predominant form.The in vivo studies revealed that the addition of methionine inhibited enzyme activity. In addition, 1 mg/ml cycloleucine (in the presence of methionine) induced the activity of this enzyme, indicating that SAM (along with methionine) is a co-effector of enzyme activity and/or synthesis.Ball State UniversityMuncie, IN 47306