Development of pseudomonas aeruginosa as a MICROBiAL Factory


Pseudomonas aeruginosa produces numerous "value-added" compounds including antifungal agents, antibiotics, biosurfactants, and biodegradable plastic.  We are involved in metabolic and genetic engineering of the bacterium for optimal production of high-value molecules.


Metabolic engineering of P. aeruginosa to improve biosurfactant production: My laboratory has been involved in metabolic engineering of bacteria for conversion of waste products such as biodiesel glycerol into value-added products.  The bacterium Pseudomonas aeruginosa is a ubiquitous organism that is remarkable for its ability to utilize various nutrients and to produce a variety of extracellular products including highly effective biosurfactant, rhamnolipid, and biodegradable plastic that has tensile strength of synthetic plastic.  Through genetic and metabolic engineering, we have constructed a strain of P. aeruginosa that increased the production of rhamnolipid by 15-fold when grown on glycerol as a sole carbon source.  Rhamnolipid is a highly effective biosurfactant that has a wide industrial use including waste treatment, fungicide, and for improving degradation of oil.  We are currently continuing our improvement of rhamnolipid production by P. aeruginosa.  


Characterization of an antifungal agent for crop protection: P. aeruginosa converts ricinoleic acid to 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD), a novel value-added multihydroxyl fatty acid with anti-fungal activity. TOD is active against several pathogenic fungi, including Magnaporthe grisea, the causative agent for various turf diseases and rice blast disease that results in loss of 10-30% of the rice harvest. The goal of this project is to develop efficient processes for producing TOD from P. aeruginosa to mass-produce an economically competitive and environmentally friendly biological crop protection agent.

  Sang-Jin Suh © Auburn University 2012. All rights reserved