Enzymes in carbohydrate synthesis /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1988.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | The versatility of fructose-diphosphate aldolase, acid phosphatase and glucose isomerase have been explored in the synthesis of monosaccharides. Aldolase has been found to accept a wide variety of aldehydes as substrates to yield unnatural ketose-1-phosphates. These can then be converted to ketoses and aldoses by the action of acid phosphatase and glucose isomerase. Six, seven and eight carbon sugars have been synthesized with this methodology. They include 5, 6 and 7-deoxy, 6-0-methyl, 6-azido, 6-amido, and 5 and 6 alkylated compounds. When a racemic aldehyde is used, there is not an equal distribution of products. The reaction, which is readily reversible, is thermodynamically controlled. Arsenate and vanadate esters of dihydroxyacetone were investigated as potential mimics of dihydroxyacetone phosphate. The arsenate ester, which forms spontaneously in solution, is a good substrate for aldolase. Vanadate, on the other hand, oxidizes dihydroxyacetone and does not participate in the aldol condensation. Reactions of the arsenate ester and racemic aldehyde yielded a kinetic distribution of products, due to the nonreversible nature of this reaction. Β-D-Glucosidase was investigated in the potential glucosidation of enols of 1,2-diones. Simple glucosides were readily formed using D-cellobiose or p-nitrophenyl-β-D-glucopyranoside and the corresponding alcohol. However, the enol was determined to be either a poor substrate or, more likely, the product was too labile under the reaction conditions. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Chemistry." |
| Physical Description: | xvii, 176 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 168-175). |