Polyhydroxybutyrate (PHB) is a biopolymer that can be used as a biodegradable thermoplastic material. PHB is produced by micro-organisms as a form of energy storage during stress. The genes involved in the pathway can be isolated and utilized for the large scale production of PHB in other micro-organisms or plants. The search towards PHB based plastic materials production with the cost and properties competitive to the petrochemical based plastic is focused in many industrial and research organizations.