Abstract

An overview on the properties, composition and metabolism in microorganisms of different forms of organic and inorganic biopolymers present in nature will be given. Special emphasis will be placed on polyhydroxyalkanoates (PHAs), polyphosphate (polyP) and polyisoprene (rubbers). Recently obtained new insights in the formation and utilization of polyhydroxybutyrate (PHB) and polyP in the betaproteobacterium Ralstonia eutropha will be shown. Comparative analysis of proteome data of different cell fractions revealed the identification of new specifically PHB granule associated proteins and specifically polyP associated proteins in R. eutropha. Consequences of these findings on the metabolism of storage polymers will be discussed. Mechanistic insights in the degradation mechanisms of rubbers by two different types of rubber-degrading enzymes (rubber oxygenase RoxA and latex clearing protein Lcp) will be also shown.