Production of unusual bacterial polyesters by Pseudomonas oleovorans through cometabolism

Pseudomonas oleovorans is an adaptable, aerobic bacterium that can produce a wide range of storage polyesters (poly‐β‐hydroxyalkanoates, PHAs). With few exceptions, the PHAs obtained when this bacterium is grown with single organic substrates capable of polymer production are generally copolymers. With two different polymer‐producing substrates the copolymers formed contain units derived from each substrate often in direct proportion to the amounts in the medium. With such substrates or with non‐producing substrates, or with non‐growth substrates, the ability of P. oleovorans to utilize different types of individual organic compounds can be classified into three different categories, as follows: group A—the organic compound can support both growth and polymer production; or group B—the organic compound can support growth but not polymer production; or group C—the organic compounds cannot support growth. For organic compounds in groups B and C, new and unusual copolymers containing units derived from these substrates can often be obtained if that compound is cofed with a good polymer‐producing substrate for P. oleovorans , such as either octanoic acid or nonanoic acid. The PHAs obtained by this type of cometabolism from a variety of such substrates are described.