Sunday, August 11, 2013
Pavilion (Sheraton San Diego)
Recent fluctuations in oil prices and undesired gas emissions from petrochemical industries have sparked widespread interest in the microbial production of carbon-based chemicals from biorenewable sources. The development of microbial “cell factories” to complement fossil-based chemicals currently produced by petrochemical industries offers an economically feasible and environmentally friendly process for the production of biorenewable chemicals. However, barriers such as high toxicity and limited productivity need to be addressed to enable industrial-scale production of these chemicals. Systems biology tools including transcriptomics and proteomics, in combination with metabolic engineering strategies, provide great opportunities to analyze these microbial systems and to develop engineering strategies for addressing these issues. This work presents two cases in which 2D gel electrophoresis and DNA microarray analyses have been used to identify targets for improving (a) tolerance of E. coli to short-chain fatty acids, and (b) understanding and metabolism of glycerol as a feedstock for the production of a wide range of biorenewable chemicals. In order to improve tolerance of E. coli to short-chain fatty acids, a proteomic analysis was performed to compare protein expression under different concentrations of octanoic acid. From 12 proteins that were identified by Mass Spectrometry, OmpF, an outer-membrane porin, has exhibited greatest effects over cellular growth and has stood out as a potential target for modification. In addition, E. coli strains with impaired glycerol consumption have been compared to strains with complete ability to ferment glycerol in an attempt to gain better understanding of glycerol metabolism and identify targets for improving it.