Poly-3-Hydroxybutyrate As An Example Of A Biopolymer Produced By Methanotrophic Bacteria

The objective of this review paper is to present the current state of knowledge about poly-3-hydroxybutyrate produced by methanotrophic bacteria. Methanotrophs are a large group of microorganisms, which live in different kinds of environment, but they preferably occupy places with high methane production, such as swamps, peat bogs, rice fields, or widely understood geological deposits. Methanotrophic bacteria are an important object of research for specialists of environmental biotechnology, are increasingly identified in environmental samples. Methanotrophs are Gram-negative microorganisms, they belonging to the group of Proteobacteria and classified as methylotrophs. In their metabolic cycle, they use methane as the main source of coal and energy. PHB is a linear polyester of 3-hydroxybutyric acid, PHB is accumulated in microorganisms during physiological stress, triggered by the deficit of biogenic elements, such as nitrogen or phosphorus and when the concentration of carbon source is high. Poly-3-hydroxybutyrate belongs to a large group of biodegradable polymers known as polyhydroxyalkanoates. PHB has a similar physico-chemical properties as conventional polymers. PHB is environmentally friendly due to the fast biodegradation and production non-toxic waste during degradation. For this reason poli-3-hydroxybutyrate is an interesting alternative to petrochemical polymers. PHB found a lot of applications in industry, medicine and pharmacy.