1,3-Propanediol (PDO) is an appealing chemical for use in the production of new types of polymers such as polytrimethyleneterephthalate (PTT). In particular, the recent successful replacement of chemical routes for PDO production by a biological process makes PDO a prominent green chemical from renewable materials. This chapter first briefly describes the properties, uses, and production methods of PDO and PTT. Emphases are then laid on describing the biotechnological production of PDO in more detail, ranging from substrates, microorganisms, metabolic pathway engineering to fermentation processes and downstream processing. The different fermentation processes and downstream processing methods are compared, in terms of both technology and economy. It is evident that not only the glucose-based bioprocess, but also the bioconversion of glycerol into PDO is technologically and economically sound. Especially, a new biorefinery concept using a microbial community for glycerol bioconversion into PDO and bioenergy is illustrated which is attractive due to its simplicity and very low production costs. Perspectives and further research needs to this end are discussed.
