Abstract

Biopolymers comprise in total eight classes according to their constituents and the covalent linkages of these constituents. Beside nucleic acids and proteins five of them can be produced by microorganisms in biotechnological processes. These are polysaccharides, polyamides, polyesters, polythioesters and polyphosphate. The only biopolymers that are not synthesized by microorganisms are polyisoprenoides. Their synthesis remains so far a domain of plants and a few fungi. All microbially produced polymers can be produced from renewable resources and their constituents. All microbially produced polymers except one are biodegradable. The exception is exhibited by polythioesters which are persistent and cannot be degraded by organisms and enzymes, thereby disturbing the paradigm that any compound, which is synthesized by the living matter, is biodegradable. Other non-biodegradable polymers with biosynthesis steps involved are (bio)polyethylene and (bio)propylene which can be obtained by chemical processes for example from ethanol produced by the fermentation of carbohydrates by Saccharomyces cerevisiae or other ethanol producing microorganisms. This lecture will give an overview about technically relevant biopolymers and their features as well as about the peculiarities of their production.