Genetically engineered Pseudomonas: a factory of new bioplastics with broad applications

OLIVERA,E.; CARNICERO,D.; JODRA,R.; MIÑAMBRES,B.; GARCIA,B.; ABRAHAM,G.A.; GALLARDO,A.; SAN ROMAN,J; GARCIA,J.L.; NAHARRO,G.; LUENGO,J.M.

ENVIRONMENTAL MICROBIOLOGY

Blackwell Science Ltd.

Lugar: Oxford, United Kingdom; Año: 2001 vol. 3 p. 612 - 618

1462-2912

New bioplastics containing aromatic, or mixtures of aliphatic and aromatic monomers have been obtained by using genetically engineered strains of Pseudomonas putida. The mutation (-) or the deletion (ƒ´) of some of the genes involved in the b-oxidation pathway (fadA-, fadB- ƒ´fadA or ƒ´fadBA mutants) elicits a strong intracellular accumulation of unusual homo- or copolymers that dramatically alter the morphology of these bacteria (more than 90% of the cytoplasm is occupied by these macromolecules). The introduction of a blockade in the b-oxidation pathway, or in other related catabolic routes, have allowed: (i) the synthesis of polymers other than those accumulated in the wild-type (as regards both monomer size and relative percentage), whose composition can be modified at will; (ii) the accumulation of certain intermediates that are rapidly catabolized in the wild-type, and (iii) to obtain end catabolites that as in the case of phenylacetic acid, phenylbutyric acid, trans-cinnamic acid or their derivatives, have important medical or pharmaceutical applications (antitumoural, radiopotentiators, chemopreventive, analgesic or antihelmintic). Furthermore, we have obtained polymeric microspheres that could be used as drug vehicles.