SOCED 7 |
| Nature relies on polymers for a wide variety of its structures and functions, as do we. The first practical plastics, fibers and films were based on the chemical modification of cellulose, which is produced by plants as a structural material. Cellulose can be chemically modified to make it soluble and fusible while still retaining its linear, high molecular weight structure necessary for crystallinity and useful mechanical properies in commercial cellophane films and rayon fibers. Bacterial polyesters are also linear, crystallizable polymers of very high molecular weight, but these macromolecules are produced by microorganisms as a reserve food and energy supply. They are ideal intracellular storage materials because they are water insoluble but can be rapidly degraded to their metabolizable monomers. That is, like cellulose and all other natural polymers, there exists specialized enzymes, which are themselves polymers, that can catalyze both the polymerization and depolymerization reactions involved in their synthesis and degradation. The production and activity of these enzymes by bacteria and the fascinating history of the discovery, identification and application of bacterial polyesters will be discussed, as will the genetic engineering of microorganisms and plants for their production by the wonders of biotechnology. |
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Eminent Scientist Lecture and Luncheon Featuring Robert W. Lenz
11:45 AM-1:00 PM, Monday, August 20, 2007 Westin Copley Place -- St. George A/B, Oral
Society Committee on Education |