2010 Summer NC State Undergraduate Research Symposium

Session Time : 8/5/10 1:00 PM - 8/5/10 4:00 PM

Content Area : Synthetic Biology REU

Student Presenters :
Jacob Thomas Dums Biotechnology

Mentors and/or Co-Authors :
Heike Sederoff Plant Biology

Abstract Title : Jet Fuels from Microalgae: Genetic Engineering of Dunaliella for Biofuel

Abstract :
The genetic engineering of the marine microalga Dunaliella chloroplast will be required for biofuel production, because fatty acid biosynthesis occurs in the chloroplast and fatty acids are the precursors that will be used to produce jet fuel. Engineering of the chloroplast will first be optimized because it has no silencing mechanism, homologous recombination can be used for site specific integration, and polycistronic cassettes can be expressed. The genes used for transformation will be cloned primarily from Archaebacteria. Archaebacterial genes have the advantage of not being under the same regulatory control as eukaryote genes, allowing the archaebacterial genes to be expressed without inhibition. However, chloroplast transformation in Dunaliella has not been achieved yet. Transformation of heterologous proteins requires optimization of the codon sequence of the target genes for the host organism and identification of a selection mechanism of transgenic cells after successful transformation. As a test system, we used superoxide reductase from Pyrococcus furiosus and Green Fluorescent Protein from Aequorea victoria. In order to facilitate homologous recombination, we have chosen to insert our cassette into the inverted repeat region of the chloroplast because it is known as a highly active region of gene expression. Different parameters including particle velocity, working distance, repetition of bombardment, and DNA concentration were also tested for the introduction of the transformation cassette using the biolistic method. The long term objective is to develop a protocol for the expression in the chloroplast of genes that will allow the production of fatty acids targeted toward jet fuel production.